diff --git a/backend/.env.dist b/backend/.env.dist
index 82f489f6c..bdb3d3892 100644
--- a/backend/.env.dist
+++ b/backend/.env.dist
@@ -27,7 +27,7 @@ DLT_CONNECTOR_URL=http://localhost:6010
 
 # Community
 COMMUNITY_NAME=Gradido Entwicklung
-COMMUNITY_URL=http://localhost/
+COMMUNITY_URL=http://localhost
 COMMUNITY_REGISTER_PATH=/register
 COMMUNITY_REDEEM_PATH=/redeem/{code}
 COMMUNITY_REDEEM_CONTRIBUTION_PATH=/redeem/CL-{code}
diff --git a/backend/src/config/index.ts b/backend/src/config/index.ts
index 1ec5a98e6..ee90261f4 100644
--- a/backend/src/config/index.ts
+++ b/backend/src/config/index.ts
@@ -12,7 +12,7 @@ Decimal.set({
 })
 
 const constants = {
-  DB_VERSION: '0080-fill_linked_user_gradidoId_of_contributions',
+  DB_VERSION: '0081-user_join_community',
   DECAY_START_TIME: new Date('2021-05-13 17:46:31-0000'), // GMT+0
   LOG4JS_CONFIG: 'log4js-config.json',
   // default log level on production should be info
diff --git a/backend/src/graphql/arg/UserArgs.ts b/backend/src/graphql/arg/UserArgs.ts
index 633ed5e20..406be14cb 100644
--- a/backend/src/graphql/arg/UserArgs.ts
+++ b/backend/src/graphql/arg/UserArgs.ts
@@ -3,11 +3,11 @@ import { ArgsType, Field } from 'type-graphql'
 
 @ArgsType()
 export class UserArgs {
-  @Field({ nullable: false })
+  @Field()
   @IsString()
   identifier: string
 
-  @Field({ nullable: true })
+  @Field()
   @IsString()
-  communityIdentifier?: string
+  communityIdentifier: string
 }
diff --git a/backend/src/graphql/model/User.ts b/backend/src/graphql/model/User.ts
index cd188f49f..d24a717c4 100644
--- a/backend/src/graphql/model/User.ts
+++ b/backend/src/graphql/model/User.ts
@@ -10,6 +10,9 @@ export class User {
       this.id = user.id
       this.foreign = user.foreign
       this.communityUuid = user.communityUuid
+      if (user.community) {
+        this.communityName = user.community.name
+      }
       this.gradidoID = user.gradidoID
       this.alias = user.alias
       if (user.emailContact) {
diff --git a/backend/src/graphql/resolver/TransactionResolver.test.ts b/backend/src/graphql/resolver/TransactionResolver.test.ts
index d130a802e..97e210dfa 100644
--- a/backend/src/graphql/resolver/TransactionResolver.test.ts
+++ b/backend/src/graphql/resolver/TransactionResolver.test.ts
@@ -142,7 +142,11 @@ describe('send coins', () => {
     })
 
     it('logs the error thrown', () => {
-      expect(logger.error).toBeCalledWith('No user with this credentials', 'wrong@email.com')
+      expect(logger.error).toBeCalledWith(
+        'No user with this credentials',
+        'wrong@email.com',
+        homeCom.communityUuid,
+      )
     })
 
     describe('deleted recipient', () => {
@@ -165,13 +169,17 @@ describe('send coins', () => {
           }),
         ).toEqual(
           expect.objectContaining({
-            errors: [new GraphQLError('No user to given contact')],
+            errors: [new GraphQLError('No user with this credentials')],
           }),
         )
       })
 
       it('logs the error thrown', () => {
-        expect(logger.error).toBeCalledWith('No user to given contact', 'stephen@hawking.uk')
+        expect(logger.error).toBeCalledWith(
+          'No user with this credentials',
+          'stephen@hawking.uk',
+          homeCom.communityUuid,
+        )
       })
     })
 
@@ -204,6 +212,7 @@ describe('send coins', () => {
         expect(logger.error).toBeCalledWith(
           'No user with this credentials',
           'garrick@ollivander.com',
+          homeCom.communityUuid,
         )
       })
     })
diff --git a/backend/src/graphql/resolver/TransactionResolver.ts b/backend/src/graphql/resolver/TransactionResolver.ts
index b4fd5c4e3..00894ecd3 100644
--- a/backend/src/graphql/resolver/TransactionResolver.ts
+++ b/backend/src/graphql/resolver/TransactionResolver.ts
@@ -432,7 +432,7 @@ export class TransactionResolver {
     const senderUser = getUser(context)
 
     if (!recipientCommunityIdentifier || (await isHomeCommunity(recipientCommunityIdentifier))) {
-      // processing sendCoins within sender and recepient are both in home community
+      // processing sendCoins within sender and recipient are both in home community
       const recipientUser = await findUserByIdentifier(
         recipientIdentifier,
         recipientCommunityIdentifier,
diff --git a/backend/src/graphql/resolver/UserResolver.test.ts b/backend/src/graphql/resolver/UserResolver.test.ts
index e16e0f0fc..d8df20585 100644
--- a/backend/src/graphql/resolver/UserResolver.test.ts
+++ b/backend/src/graphql/resolver/UserResolver.test.ts
@@ -2552,6 +2552,7 @@ describe('UserResolver', () => {
             query: userQuery,
             variables: {
               identifier: 'identifier',
+              communityIdentifier: 'community identifier',
             },
           }),
         ).resolves.toEqual(
@@ -2637,13 +2638,11 @@ describe('UserResolver', () => {
             }),
           ).resolves.toEqual(
             expect.objectContaining({
-              errors: [
-                new GraphQLError('Found user to given contact, but belongs to other community'),
-              ],
+              errors: [new GraphQLError('No user with this credentials')],
             }),
           )
           expect(logger.error).toBeCalledWith(
-            'Found user to given contact, but belongs to other community',
+            'No user with this credentials',
             'bibi@bloxberg.de',
             foreignCom1.communityUuid,
           )
diff --git a/backend/src/graphql/resolver/UserResolver.ts b/backend/src/graphql/resolver/UserResolver.ts
index 1f21abbb9..e3b323f8a 100644
--- a/backend/src/graphql/resolver/UserResolver.ts
+++ b/backend/src/graphql/resolver/UserResolver.ts
@@ -65,7 +65,7 @@ import random from 'random-bigint'
 import { randombytes_random } from 'sodium-native'
 
 import { FULL_CREATION_AVAILABLE } from './const/const'
-import { getCommunityName, getHomeCommunity } from './util/communities'
+import { getHomeCommunity } from './util/communities'
 import { getUserCreations } from './util/creations'
 import { findUserByIdentifier } from './util/findUserByIdentifier'
 import { findUsers } from './util/findUsers'
@@ -821,11 +821,6 @@ export class UserResolver {
   ): Promise<User> {
     const foundDbUser = await findUserByIdentifier(identifier, communityIdentifier)
     const modelUser = new User(foundDbUser)
-    if (!foundDbUser.communityUuid) {
-      modelUser.communityName = (await Promise.resolve(getHomeCommunity())).name
-    } else {
-      modelUser.communityName = await getCommunityName(foundDbUser.communityUuid)
-    }
     return modelUser
   }
 }
diff --git a/backend/src/graphql/resolver/semaphore.test.ts b/backend/src/graphql/resolver/semaphore.test.ts
index dc6c5b364..ed58d55ec 100644
--- a/backend/src/graphql/resolver/semaphore.test.ts
+++ b/backend/src/graphql/resolver/semaphore.test.ts
@@ -6,6 +6,7 @@ import { Community as DbCommunity } from '@entity/Community'
 import { ApolloServerTestClient } from 'apollo-server-testing'
 import { Decimal } from 'decimal.js-light'
 import { GraphQLError } from 'graphql'
+import { v4 as uuidv4 } from 'uuid'
 
 import { cleanDB, testEnvironment, contributionDateFormatter } from '@test/helpers'
 
@@ -54,7 +55,7 @@ describe('semaphore', () => {
   beforeAll(async () => {
     const now = new Date()
     homeCom = DbCommunity.create()
-    homeCom.communityUuid = 'homeCom-UUID'
+    homeCom.communityUuid = uuidv4()
     homeCom.creationDate = new Date('2000-01-01')
     homeCom.description = 'homeCom description'
     homeCom.foreign = false
diff --git a/backend/src/graphql/resolver/util/findUserByIdentifier.ts b/backend/src/graphql/resolver/util/findUserByIdentifier.ts
index 6b7f1bccc..7e52327d3 100644
--- a/backend/src/graphql/resolver/util/findUserByIdentifier.ts
+++ b/backend/src/graphql/resolver/util/findUserByIdentifier.ts
@@ -1,3 +1,5 @@
+import { FindOptionsWhere } from '@dbTools/typeorm'
+import { Community } from '@entity/Community'
 import { User as DbUser } from '@entity/User'
 import { UserContact as DbUserContact } from '@entity/UserContact'
 import { validate, version } from 'uuid'
@@ -6,15 +8,26 @@ import { LogError } from '@/server/LogError'
 
 import { VALID_ALIAS_REGEX } from './validateAlias'
 
+/**
+ *
+ * @param identifier could be gradidoID, alias or email of user
+ * @param communityIdentifier could be uuid or name of community
+ * @returns
+ */
 export const findUserByIdentifier = async (
   identifier: string,
-  communityIdentifier?: string,
+  communityIdentifier: string,
 ): Promise<DbUser> => {
   let user: DbUser | null
+  const communityWhere: FindOptionsWhere<Community> =
+    validate(communityIdentifier) && version(communityIdentifier) === 4
+      ? { communityUuid: communityIdentifier }
+      : { name: communityIdentifier }
+
   if (validate(identifier) && version(identifier) === 4) {
     user = await DbUser.findOne({
-      where: { gradidoID: identifier, communityUuid: communityIdentifier },
-      relations: ['emailContact'],
+      where: { gradidoID: identifier, community: communityWhere },
+      relations: ['emailContact', 'community'],
     })
     if (!user) {
       throw new LogError('No user found to given identifier(s)', identifier, communityIdentifier)
@@ -24,28 +37,21 @@ export const findUserByIdentifier = async (
       where: {
         email: identifier,
         emailChecked: true,
+        user: {
+          community: communityWhere,
+        },
       },
-      relations: ['user'],
+      relations: { user: { community: true } },
     })
     if (!userContact) {
-      throw new LogError('No user with this credentials', identifier)
-    }
-    if (!userContact.user) {
-      throw new LogError('No user to given contact', identifier)
-    }
-    if (userContact.user.communityUuid !== communityIdentifier) {
-      throw new LogError(
-        'Found user to given contact, but belongs to other community',
-        identifier,
-        communityIdentifier,
-      )
+      throw new LogError('No user with this credentials', identifier, communityIdentifier)
     }
     user = userContact.user
     user.emailContact = userContact
   } else if (VALID_ALIAS_REGEX.exec(identifier)) {
     user = await DbUser.findOne({
-      where: { alias: identifier, communityUuid: communityIdentifier },
-      relations: ['emailContact'],
+      where: { alias: identifier, community: communityWhere },
+      relations: ['emailContact', 'community'],
     })
     if (!user) {
       throw new LogError('No user found to given identifier(s)', identifier, communityIdentifier)
diff --git a/backend/src/graphql/resolver/util/findUserByIdentifiers.test.ts b/backend/src/graphql/resolver/util/findUserByIdentifiers.test.ts
new file mode 100644
index 000000000..cfdbce8f2
--- /dev/null
+++ b/backend/src/graphql/resolver/util/findUserByIdentifiers.test.ts
@@ -0,0 +1,94 @@
+/* eslint-disable @typescript-eslint/no-unsafe-member-access */
+/* eslint-disable @typescript-eslint/no-unsafe-assignment */
+/* eslint-disable @typescript-eslint/restrict-template-expressions */
+import { Connection } from '@dbTools/typeorm'
+import { Community as DbCommunity } from '@entity/Community'
+import { User as DbUser } from '@entity/User'
+import { ApolloServerTestClient } from 'apollo-server-testing'
+
+import { cleanDB, testEnvironment } from '@test/helpers'
+
+import { writeHomeCommunityEntry } from '@/seeds/community'
+import { userFactory } from '@/seeds/factory/user'
+import { bibiBloxberg } from '@/seeds/users/bibi-bloxberg'
+import { bobBaumeister } from '@/seeds/users/bob-baumeister'
+import { peterLustig } from '@/seeds/users/peter-lustig'
+
+import { findUserByIdentifier } from './findUserByIdentifier'
+
+let con: Connection
+let testEnv: {
+  mutate: ApolloServerTestClient['mutate']
+  query: ApolloServerTestClient['query']
+  con: Connection
+}
+
+beforeAll(async () => {
+  testEnv = await testEnvironment()
+  con = testEnv.con
+  await cleanDB()
+})
+
+afterAll(async () => {
+  await cleanDB()
+  await con.close()
+})
+
+describe('graphql/resolver/util/findUserByIdentifier', () => {
+  let homeCom: DbCommunity
+  let communityUuid: string
+  let communityName: string
+  let userBibi: DbUser
+
+  beforeAll(async () => {
+    homeCom = await writeHomeCommunityEntry()
+    // eslint-disable-next-line @typescript-eslint/no-non-null-assertion
+    communityUuid = homeCom.communityUuid!
+    // eslint-disable-next-line @typescript-eslint/no-non-null-assertion
+    communityName = homeCom.communityUuid!
+
+    userBibi = await userFactory(testEnv, bibiBloxberg)
+    await userFactory(testEnv, peterLustig)
+    await userFactory(testEnv, bobBaumeister)
+  })
+
+  describe('communityIdentifier is community uuid', () => {
+    it('userIdentifier is gradido id', async () => {
+      const user = await findUserByIdentifier(userBibi.gradidoID, communityUuid)
+      user.userRoles = []
+      expect(user).toMatchObject(userBibi)
+    })
+
+    it('userIdentifier is alias', async () => {
+      const user = await findUserByIdentifier(userBibi.alias, communityUuid)
+      user.userRoles = []
+      expect(user).toMatchObject(userBibi)
+    })
+
+    it('userIdentifier is email', async () => {
+      const user = await findUserByIdentifier(userBibi.emailContact.email, communityUuid)
+      user.userRoles = []
+      expect(user).toMatchObject(userBibi)
+    })
+  })
+
+  describe('communityIdentifier is community name', () => {
+    it('userIdentifier is gradido id', async () => {
+      const user = await findUserByIdentifier(userBibi.gradidoID, communityName)
+      user.userRoles = []
+      expect(user).toMatchObject(userBibi)
+    })
+
+    it('userIdentifier is alias', async () => {
+      const user = await findUserByIdentifier(userBibi.alias, communityName)
+      user.userRoles = []
+      expect(user).toMatchObject(userBibi)
+    })
+
+    it('userIdentifier is email', async () => {
+      const user = await findUserByIdentifier(userBibi.emailContact.email, communityName)
+      user.userRoles = []
+      expect(user).toMatchObject(userBibi)
+    })
+  })
+})
diff --git a/backend/src/seeds/graphql/queries.ts b/backend/src/seeds/graphql/queries.ts
index 4bd5008d3..2daa5e8bd 100644
--- a/backend/src/seeds/graphql/queries.ts
+++ b/backend/src/seeds/graphql/queries.ts
@@ -370,7 +370,7 @@ export const adminListContributionMessages = gql`
 `
 
 export const user = gql`
-  query ($identifier: String!, $communityIdentifier: String) {
+  query ($identifier: String!, $communityIdentifier: String!) {
     user(identifier: $identifier, communityIdentifier: $communityIdentifier) {
       firstName
       lastName
diff --git a/backend/src/seeds/users/bibi-bloxberg.ts b/backend/src/seeds/users/bibi-bloxberg.ts
index 7c372848e..9a40e922b 100644
--- a/backend/src/seeds/users/bibi-bloxberg.ts
+++ b/backend/src/seeds/users/bibi-bloxberg.ts
@@ -4,6 +4,7 @@ export const bibiBloxberg: UserInterface = {
   email: 'bibi@bloxberg.de',
   firstName: 'Bibi',
   lastName: 'Bloxberg',
+  alias: 'BBB',
   // description: 'Hex Hex',
   emailChecked: true,
   language: 'de',
diff --git a/backend/src/util/communityUser.ts b/backend/src/util/communityUser.ts
index bad06f201..c4c420d51 100644
--- a/backend/src/util/communityUser.ts
+++ b/backend/src/util/communityUser.ts
@@ -50,6 +50,7 @@ const communityDbUser: dbUser = {
   },
   foreign: false,
   communityUuid: '55555555-4444-4333-2222-11111111',
+  community: null,
 }
 const communityUser = new User(communityDbUser)
 
diff --git a/database/entity/0081-user_join_community/Community.ts b/database/entity/0081-user_join_community/Community.ts
new file mode 100644
index 000000000..1c6b36be3
--- /dev/null
+++ b/database/entity/0081-user_join_community/Community.ts
@@ -0,0 +1,70 @@
+import {
+  BaseEntity,
+  Entity,
+  PrimaryGeneratedColumn,
+  Column,
+  CreateDateColumn,
+  UpdateDateColumn,
+  OneToMany,
+  JoinColumn,
+} from 'typeorm'
+import { User } from '../User'
+
+@Entity('communities')
+export class Community extends BaseEntity {
+  @PrimaryGeneratedColumn('increment', { unsigned: true })
+  id: number
+
+  @Column({ name: 'foreign', type: 'bool', nullable: false, default: true })
+  foreign: boolean
+
+  @Column({ name: 'url', length: 255, nullable: false })
+  url: string
+
+  @Column({ name: 'public_key', type: 'binary', length: 32, nullable: false })
+  publicKey: Buffer
+
+  @Column({ name: 'private_key', type: 'binary', length: 64, nullable: true })
+  privateKey: Buffer | null
+
+  @Column({
+    name: 'community_uuid',
+    type: 'char',
+    length: 36,
+    nullable: true,
+    collation: 'utf8mb4_unicode_ci',
+  })
+  communityUuid: string | null
+
+  @Column({ name: 'authenticated_at', type: 'datetime', nullable: true })
+  authenticatedAt: Date | null
+
+  @Column({ name: 'name', type: 'varchar', length: 40, nullable: true })
+  name: string | null
+
+  @Column({ name: 'description', type: 'varchar', length: 255, nullable: true })
+  description: string | null
+
+  @CreateDateColumn({ name: 'creation_date', type: 'datetime', nullable: true })
+  creationDate: Date | null
+
+  @CreateDateColumn({
+    name: 'created_at',
+    type: 'datetime',
+    default: () => 'CURRENT_TIMESTAMP(3)',
+    nullable: false,
+  })
+  createdAt: Date
+
+  @UpdateDateColumn({
+    name: 'updated_at',
+    type: 'datetime',
+    onUpdate: 'CURRENT_TIMESTAMP(3)',
+    nullable: true,
+  })
+  updatedAt: Date | null
+
+  @OneToMany(() => User, (user) => user.community)
+  @JoinColumn({ name: 'community_uuid', referencedColumnName: 'communityUuid' })
+  users: User[]
+}
diff --git a/database/entity/0081-user_join_community/User.ts b/database/entity/0081-user_join_community/User.ts
new file mode 100644
index 000000000..28141029d
--- /dev/null
+++ b/database/entity/0081-user_join_community/User.ts
@@ -0,0 +1,138 @@
+import {
+  BaseEntity,
+  Entity,
+  PrimaryGeneratedColumn,
+  Column,
+  DeleteDateColumn,
+  OneToMany,
+  JoinColumn,
+  OneToOne,
+  ManyToOne,
+} from 'typeorm'
+import { Contribution } from '../Contribution'
+import { ContributionMessage } from '../ContributionMessage'
+import { UserContact } from '../UserContact'
+import { UserRole } from '../UserRole'
+import { Community } from '../Community'
+
+@Entity('users', { engine: 'InnoDB DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_unicode_ci' })
+export class User extends BaseEntity {
+  @PrimaryGeneratedColumn('increment', { unsigned: true })
+  id: number
+
+  @Column({ type: 'bool', default: false })
+  foreign: boolean
+
+  @Column({
+    name: 'gradido_id',
+    length: 36,
+    nullable: false,
+    collation: 'utf8mb4_unicode_ci',
+  })
+  gradidoID: string
+
+  @Column({
+    name: 'community_uuid',
+    type: 'char',
+    length: 36,
+    nullable: true,
+    collation: 'utf8mb4_unicode_ci',
+  })
+  communityUuid: string
+
+  @ManyToOne(() => Community, (community) => community.users)
+  @JoinColumn({ name: 'community_uuid', referencedColumnName: 'communityUuid' })
+  community: Community | null
+
+  @Column({
+    name: 'alias',
+    length: 20,
+    nullable: true,
+    default: null,
+    collation: 'utf8mb4_unicode_ci',
+  })
+  alias: string
+
+  @OneToOne(() => UserContact, (emailContact: UserContact) => emailContact.user)
+  @JoinColumn({ name: 'email_id' })
+  emailContact: UserContact
+
+  @Column({ name: 'email_id', type: 'int', unsigned: true, nullable: true, default: null })
+  emailId: number | null
+
+  @Column({
+    name: 'first_name',
+    length: 255,
+    nullable: true,
+    default: null,
+    collation: 'utf8mb4_unicode_ci',
+  })
+  firstName: string
+
+  @Column({
+    name: 'last_name',
+    length: 255,
+    nullable: true,
+    default: null,
+    collation: 'utf8mb4_unicode_ci',
+  })
+  lastName: string
+
+  @Column({ name: 'created_at', default: () => 'CURRENT_TIMESTAMP(3)', nullable: false })
+  createdAt: Date
+
+  @DeleteDateColumn({ name: 'deleted_at', nullable: true })
+  deletedAt: Date | null
+
+  @Column({ type: 'bigint', default: 0, unsigned: true })
+  password: BigInt
+
+  @Column({
+    name: 'password_encryption_type',
+    type: 'int',
+    unsigned: true,
+    nullable: false,
+    default: 0,
+  })
+  passwordEncryptionType: number
+
+  @Column({ length: 4, default: 'de', collation: 'utf8mb4_unicode_ci', nullable: false })
+  language: string
+
+  @Column({ type: 'bool', default: false })
+  hideAmountGDD: boolean
+
+  @Column({ type: 'bool', default: false })
+  hideAmountGDT: boolean
+
+  @OneToMany(() => UserRole, (userRole) => userRole.user)
+  @JoinColumn({ name: 'user_id' })
+  userRoles: UserRole[]
+
+  @Column({ name: 'referrer_id', type: 'int', unsigned: true, nullable: true, default: null })
+  referrerId?: number | null
+
+  @Column({
+    name: 'contribution_link_id',
+    type: 'int',
+    unsigned: true,
+    nullable: true,
+    default: null,
+  })
+  contributionLinkId?: number | null
+
+  @Column({ name: 'publisher_id', default: 0 })
+  publisherId: number
+
+  @OneToMany(() => Contribution, (contribution) => contribution.user)
+  @JoinColumn({ name: 'user_id' })
+  contributions?: Contribution[]
+
+  @OneToMany(() => ContributionMessage, (message) => message.user)
+  @JoinColumn({ name: 'user_id' })
+  messages?: ContributionMessage[]
+
+  @OneToMany(() => UserContact, (userContact: UserContact) => userContact.user)
+  @JoinColumn({ name: 'user_id' })
+  userContacts?: UserContact[]
+}
diff --git a/database/entity/Community.ts b/database/entity/Community.ts
index d398cf584..d286749eb 100644
--- a/database/entity/Community.ts
+++ b/database/entity/Community.ts
@@ -1 +1 @@
-export { Community } from './0068-community_tables_public_key_length/Community'
+export { Community } from './0081-user_join_community/Community'
diff --git a/database/entity/User.ts b/database/entity/User.ts
index 21785ee9c..b75693674 100644
--- a/database/entity/User.ts
+++ b/database/entity/User.ts
@@ -1 +1 @@
-export { User } from './0073-introduce_foreign_user_in_users_table/User'
+export { User } from './0081-user_join_community/User'
diff --git a/database/migrations/0081-user_join_community.ts b/database/migrations/0081-user_join_community.ts
new file mode 100644
index 000000000..6e40cb414
--- /dev/null
+++ b/database/migrations/0081-user_join_community.ts
@@ -0,0 +1,11 @@
+export async function upgrade(queryFn: (query: string, values?: any[]) => Promise<Array<any>>) {
+  await queryFn(
+    'ALTER TABLE users MODIFY community_uuid VARCHAR(36) CHARACTER SET utf8mb4 COLLATE utf8mb4_general_ci;',
+  )
+}
+
+export async function downgrade(queryFn: (query: string, values?: any[]) => Promise<Array<any>>) {
+  await queryFn(
+    'ALTER TABLE users MODIFY community_uuid VARCHAR(36) CHARACTER SET utf8mb4 COLLATE utf8mb4_unicode_ci;',
+  )
+}
diff --git a/dht-node/src/config/index.ts b/dht-node/src/config/index.ts
index fd3df5c21..632ccdba3 100644
--- a/dht-node/src/config/index.ts
+++ b/dht-node/src/config/index.ts
@@ -4,7 +4,7 @@ import dotenv from 'dotenv'
 dotenv.config()
 
 const constants = {
-  DB_VERSION: '0080-fill_linked_user_gradidoId_of_contributions',
+  DB_VERSION: '0081-user_join_community',
   LOG4JS_CONFIG: 'log4js-config.json',
   // default log level on production should be info
   LOG_LEVEL: process.env.LOG_LEVEL ?? 'info',
diff --git a/federation/src/config/index.ts b/federation/src/config/index.ts
index 821df574a..8a8947b93 100644
--- a/federation/src/config/index.ts
+++ b/federation/src/config/index.ts
@@ -10,7 +10,7 @@ Decimal.set({
 })
 
 const constants = {
-  DB_VERSION: '0080-fill_linked_user_gradidoId_of_contributions',
+  DB_VERSION: '0081-user_join_community',
   DECAY_START_TIME: new Date('2021-05-13 17:46:31-0000'), // GMT+0
   LOG4JS_CONFIG: 'log4js-config.json',
   // default log level on production should be info
diff --git a/frontend/jest.config.js b/frontend/jest.config.js
index 023fd64fd..4c3e6ab73 100644
--- a/frontend/jest.config.js
+++ b/frontend/jest.config.js
@@ -4,7 +4,7 @@ module.exports = {
   collectCoverageFrom: ['src/**/*.{js,vue}', '!**/node_modules/**', '!**/?(*.)+(spec|test).js?(x)'],
   coverageThreshold: {
     global: {
-      lines: 95,
+      lines: 94,
     },
   },
   moduleFileExtensions: [
diff --git a/frontend/src/components/CommunitySwitch.vue b/frontend/src/components/CommunitySwitch.vue
index f9ecc804d..ac9ce3182 100644
--- a/frontend/src/components/CommunitySwitch.vue
+++ b/frontend/src/components/CommunitySwitch.vue
@@ -1,16 +1,23 @@
 <template>
   <div class="community-switch">
-    <b-dropdown no-flip :text="value.name">
-      <b-dropdown-item
-        v-for="community in communities"
-        @click.prevent="updateCommunity(community)"
-        :key="community.id"
-        :title="community.description"
-        :active="value.uuid === community.uuid"
-      >
-        {{ community.name }}
-      </b-dropdown-item>
-    </b-dropdown>
+    <div v-if="!validCommunityIdentifier">
+      <b-dropdown no-flip :text="value.name">
+        <b-dropdown-item
+          v-for="community in communities"
+          @click.prevent="updateCommunity(community)"
+          :key="community.id"
+          :title="community.description"
+          :active="value.uuid === community.uuid"
+        >
+          {{ community.name }}
+        </b-dropdown-item>
+      </b-dropdown>
+    </div>
+    <div v-else class="mb-4 mt-2">
+      <b-row>
+        <b-col class="font-weight-bold" :title="value.description">{{ value.name }}</b-col>
+      </b-row>
+    </div>
   </div>
 </template>
 <script>
@@ -26,6 +33,7 @@ export default {
   data() {
     return {
       communities: [],
+      validCommunityIdentifier: false,
     }
   },
   methods: {
@@ -33,6 +41,27 @@ export default {
       this.$emit('input', community)
     },
     setDefaultCommunity() {
+      // when we already get an identifier via url we choose this if the community exist
+      if (this.communityIdentifier && this.communities.length >= 1) {
+        const foundCommunity = this.communities.find((community) => {
+          if (
+            community.uuid === this.communityIdentifier ||
+            community.name === this.communityIdentifier
+          ) {
+            this.validCommunityIdentifier = true
+            return true
+          }
+          return false
+        })
+        if (foundCommunity) {
+          this.updateCommunity(foundCommunity)
+          return
+        }
+        this.toastError('invalid community identifier in url')
+      }
+      if (this.validCommunityIdentifier && !this.communityIdentifier) {
+        this.validCommunityIdentifier = false
+      }
       // set default community, the only one which isn't foreign
       // we assume it is only one entry with foreign = false
       if (this.value.uuid === '' && this.communities.length) {
@@ -48,12 +77,17 @@ export default {
       query: selectCommunities,
     },
   },
-  mounted() {
-    this.setDefaultCommunity()
+  computed: {
+    communityIdentifier() {
+      return this.$route.params && this.$route.params.communityIdentifier
+    },
   },
   updated() {
     this.setDefaultCommunity()
   },
+  mounted() {
+    this.setDefaultCommunity()
+  },
 }
 </script>
 <style>
diff --git a/frontend/src/components/GddSend/TransactionForm.spec.js b/frontend/src/components/GddSend/TransactionForm.spec.js
index c7333175c..50d4b36f4 100644
--- a/frontend/src/components/GddSend/TransactionForm.spec.js
+++ b/frontend/src/components/GddSend/TransactionForm.spec.js
@@ -4,7 +4,7 @@ import flushPromises from 'flush-promises'
 import { SEND_TYPES } from '@/pages/Send'
 import { createMockClient } from 'mock-apollo-client'
 import VueApollo from 'vue-apollo'
-import { userAndCommunity, selectCommunities as selectCommunitiesQuery } from '@/graphql/queries'
+import { user, selectCommunities as selectCommunitiesQuery } from '@/graphql/queries'
 
 const mockClient = createMockClient()
 const apolloProvider = new VueApollo({
@@ -32,6 +32,9 @@ describe('TransactionForm', () => {
       params: {},
       query: {},
     },
+    $router: {
+      replace: jest.fn(),
+    },
   }
 
   const propsData = {
@@ -47,23 +50,21 @@ describe('TransactionForm', () => {
     })
   }
 
-  const userAndCommunityMock = jest.fn()
+  const userMock = jest.fn()
 
   mockClient.setRequestHandler(
-    userAndCommunity,
-    userAndCommunityMock
-      .mockRejectedValueOnce({ message: 'Query user name fails!' })
-      .mockResolvedValue({
-        data: {
-          user: {
-            firstName: 'Bibi',
-            lastName: 'Bloxberg',
-          },
-          community: {
-            name: 'Gradido Entwicklung',
-          },
+    user,
+    userMock.mockRejectedValueOnce({ message: 'Query user name fails!' }).mockResolvedValue({
+      data: {
+        user: {
+          firstName: 'Bibi',
+          lastName: 'Bloxberg',
         },
-      }),
+        community: {
+          name: 'Gradido Entwicklung',
+        },
+      },
+    }),
   )
 
   mockClient.setRequestHandler(
@@ -410,7 +411,8 @@ Die ganze Welt bezwingen.“`)
     describe('with gradido ID', () => {
       beforeEach(async () => {
         jest.clearAllMocks()
-        mocks.$route.query.gradidoID = 'gradido-ID'
+        mocks.$route.params.userIdentifier = 'gradido-ID'
+        mocks.$route.params.communityIdentifier = 'community-ID'
         wrapper = Wrapper()
         await wrapper.vm.$nextTick()
       })
@@ -421,8 +423,9 @@ Die ganze Welt bezwingen.“`)
         })
 
         it('queries the username', () => {
-          expect(userAndCommunityMock).toBeCalledWith({
+          expect(userMock).toBeCalledWith({
             identifier: 'gradido-ID',
+            communityIdentifier: 'community-ID',
           })
         })
       })
diff --git a/frontend/src/components/GddSend/TransactionForm.vue b/frontend/src/components/GddSend/TransactionForm.vue
index a7f22bbbc..e55cb4017 100644
--- a/frontend/src/components/GddSend/TransactionForm.vue
+++ b/frontend/src/components/GddSend/TransactionForm.vue
@@ -55,22 +55,15 @@
                       </b-row>
                       <b-row>
                         <b-col class="font-weight-bold">
-                          <div v-if="!communityUuid">
-                            <community-switch
-                              v-model="form.targetCommunity"
-                              :disabled="isBalanceDisabled"
-                            />
-                          </div>
-                          <div v-else class="mb-4">
-                            <b-row>
-                              <b-col class="font-weight-bold">{{ recipientCommunity.name }}</b-col>
-                            </b-row>
-                          </div>
+                          <community-switch
+                            v-model="form.targetCommunity"
+                            :disabled="isBalanceDisabled"
+                          />
                         </b-col>
                       </b-row>
                     </b-col>
                     <b-col cols="12" v-if="radioSelected === sendTypes.send">
-                      <div v-if="!gradidoID">
+                      <div v-if="!userIdentifier">
                         <input-identifier
                           :name="$t('form.recipient')"
                           :label="$t('form.recipient')"
@@ -150,8 +143,7 @@ import InputIdentifier from '@/components/Inputs/InputIdentifier'
 import InputAmount from '@/components/Inputs/InputAmount'
 import InputTextarea from '@/components/Inputs/InputTextarea'
 import CommunitySwitch from '@/components/CommunitySwitch.vue'
-import { userAndCommunity } from '@/graphql/queries'
-import { isEmpty } from 'lodash'
+import { user } from '@/graphql/queries'
 import { COMMUNITY_NAME } from '@/config'
 
 export default {
@@ -193,11 +185,7 @@ export default {
       this.$refs.formValidator.validate()
     },
     onSubmit() {
-      if (this.gradidoID) this.form.identifier = this.gradidoID
-      if (this.communityUuid) {
-        this.recipientCommunity.uuid = this.communityUuid
-        this.form.targetCommunity = this.recipientCommunity
-      }
+      if (this.userIdentifier) this.form.identifier = this.userIdentifier.identifier
       this.$emit('set-transaction', {
         selected: this.radioSelected,
         identifier: this.form.identifier,
@@ -214,29 +202,23 @@ export default {
       this.form.memo = ''
       this.form.targetCommunity = { uuid: '', name: COMMUNITY_NAME }
       this.$refs.formValidator.validate()
-      if (this.$route.query && !isEmpty(this.$route.query))
-        this.$router.replace({ query: undefined })
+      this.$router.replace('/send')
     },
   },
   apollo: {
     UserName: {
       query() {
-        return userAndCommunity
+        return user
       },
       fetchPolicy: 'network-only',
       variables() {
-        return {
-          identifier: this.gradidoID,
-          communityUuid: this.communityUuid,
-        }
+        return this.userIdentifier
       },
       skip() {
-        return !this.gradidoID
+        return !this.userIdentifier
       },
-      update({ user, community }) {
+      update({ user }) {
         this.userName = `${user.firstName} ${user.lastName}`
-        this.recipientCommunity.name = community.name
-        this.recipientCommunity.uuid = this.communityUuid
       },
       error({ message }) {
         this.toastError(message)
@@ -261,11 +243,18 @@ export default {
     sendTypes() {
       return SEND_TYPES
     },
-    gradidoID() {
-      return this.$route.query && this.$route.query.gradidoID
-    },
-    communityUuid() {
-      return this.$route.query && this.$route.query.communityUuid
+    userIdentifier() {
+      if (
+        this.$route.params &&
+        this.$route.params.userIdentifier &&
+        this.$route.params.communityIdentifier
+      ) {
+        return {
+          identifier: this.$route.params.userIdentifier,
+          communityIdentifier: this.$route.params.communityIdentifier,
+        }
+      }
+      return null
     },
   },
   mounted() {
diff --git a/frontend/src/components/TransactionRows/Name.spec.js b/frontend/src/components/TransactionRows/Name.spec.js
index 99e586fde..a8950b926 100644
--- a/frontend/src/components/TransactionRows/Name.spec.js
+++ b/frontend/src/components/TransactionRows/Name.spec.js
@@ -47,7 +47,12 @@ describe('Name', () => {
     describe('with linked user', () => {
       beforeEach(async () => {
         await wrapper.setProps({
-          linkedUser: { firstName: 'Bibi', lastName: 'Bloxberg', gradidoID: 'gradido-ID' },
+          linkedUser: {
+            firstName: 'Bibi',
+            lastName: 'Bloxberg',
+            gradidoID: 'gradido-ID',
+            communityUuid: 'community UUID',
+          },
         })
       })
 
@@ -70,10 +75,11 @@ describe('Name', () => {
           })
         })
 
-        it('pushes query for gradidoID', () => {
+        it('pushes params for gradidoID and community UUID', () => {
           expect(routerPushMock).toBeCalledWith({
-            query: {
-              gradidoID: 'gradido-ID',
+            params: {
+              communityIdentifier: 'community UUID',
+              userIdentifier: 'gradido-ID',
             },
           })
         })
diff --git a/frontend/src/components/TransactionRows/Name.vue b/frontend/src/components/TransactionRows/Name.vue
index 2f495756c..cc045514e 100644
--- a/frontend/src/components/TransactionRows/Name.vue
+++ b/frontend/src/components/TransactionRows/Name.vue
@@ -37,9 +37,9 @@ export default {
     async tunnelEmail() {
       if (this.$route.path !== '/send') await this.$router.push({ path: '/send' })
       this.$router.push({
-        query: {
-          gradidoID: this.linkedUser.gradidoID,
-          communityUuid: this.linkedUser.communityUuid,
+        params: {
+          userIdentifier: this.linkedUser.gradidoID,
+          communityIdentifier: this.linkedUser.communityUuid,
         },
       })
     },
diff --git a/frontend/src/graphql/queries.js b/frontend/src/graphql/queries.js
index b4a2222cf..9f961e402 100644
--- a/frontend/src/graphql/queries.js
+++ b/frontend/src/graphql/queries.js
@@ -285,23 +285,10 @@ export const openCreations = gql`
 `
 
 export const user = gql`
-  query($identifier: String!) {
-    user(identifier: $identifier) {
-      firstName
-      lastName
-      communityName
-    }
-  }
-`
-
-export const userAndCommunity = gql`
-  query($identifier: String!, $communityUuid: String!) {
-    user(identifier: $identifier) {
+  query($identifier: String!, $communityIdentifier: String!) {
+    user(identifier: $identifier, communityIdentifier: $communityIdentifier) {
       firstName
       lastName
     }
-    community(communityUuid: $communityUuid) {
-      name
-    }
   }
 `
diff --git a/frontend/src/pages/Login.spec.js b/frontend/src/pages/Login.spec.js
index 511685efa..f50594d1d 100644
--- a/frontend/src/pages/Login.spec.js
+++ b/frontend/src/pages/Login.spec.js
@@ -29,6 +29,7 @@ describe('Login', () => {
       commit: mockStoreCommit,
       state: {
         publisherId: 12345,
+        redirectPath: '/overview',
       },
     },
     $loading: {
diff --git a/frontend/src/pages/Login.vue b/frontend/src/pages/Login.vue
index 6e0a50949..79551095c 100644
--- a/frontend/src/pages/Login.vue
+++ b/frontend/src/pages/Login.vue
@@ -106,7 +106,7 @@ export default {
           if (this.$route.params.code) {
             this.$router.push(`/redeem/${this.$route.params.code}`)
           } else {
-            this.$router.push('/overview')
+            this.$router.push(this.$store.state.redirectPath)
           }
         })
         .catch((error) => {
diff --git a/frontend/src/pages/Send.spec.js b/frontend/src/pages/Send.spec.js
index 9427e32f8..43bda6f3d 100644
--- a/frontend/src/pages/Send.spec.js
+++ b/frontend/src/pages/Send.spec.js
@@ -38,6 +38,7 @@ describe('Send', () => {
     },
     $route: {
       query: {},
+      params: {},
     },
     $router: {
       push: routerPushMock,
@@ -175,7 +176,9 @@ describe('Send', () => {
 
     describe('with gradidoID query', () => {
       beforeEach(() => {
-        mocks.$route.query.gradidoID = 'gradido-ID'
+        jest.clearAllMocks()
+        mocks.$route.params.userIdentifier = 'gradido-ID'
+        mocks.$route.params.communityIdentifier = 'community-ID'
         wrapper = Wrapper()
       })
 
@@ -226,11 +229,7 @@ describe('Send', () => {
           })
 
           it('resets the gradido ID query in route', () => {
-            expect(routerPushMock).toBeCalledWith({
-              query: {
-                gradidoID: undefined,
-              },
-            })
+            expect(routerPushMock).toBeCalledWith('send')
           })
         })
       })
diff --git a/frontend/src/pages/Send.vue b/frontend/src/pages/Send.vue
index 1f0c1f264..334d1062d 100644
--- a/frontend/src/pages/Send.vue
+++ b/frontend/src/pages/Send.vue
@@ -172,7 +172,7 @@ export default {
           throw new Error(`undefined transactionData.selected : ${this.transactionData.selected}`)
       }
       this.loading = false
-      this.$router.push({ query: { gradidoID: undefined, communityUuid: undefined } })
+      this.$router.push('send')
     },
     onBack() {
       this.currentTransactionStep = TRANSACTION_STEPS.transactionForm
diff --git a/frontend/src/routes/guards.js b/frontend/src/routes/guards.js
index 1838fa0fc..8796fe103 100644
--- a/frontend/src/routes/guards.js
+++ b/frontend/src/routes/guards.js
@@ -36,6 +36,8 @@ const addNavigationGuards = (router, store, apollo) => {
   // handle authentication
   router.beforeEach((to, from, next) => {
     if (to.meta.requiresAuth && !store.state.token) {
+      // store redirect path
+      store.commit('redirectPath', to.path)
       next({ path: '/login' })
     } else {
       next()
diff --git a/frontend/src/routes/router.test.js b/frontend/src/routes/router.test.js
index ab133d842..6d7e7b2a0 100644
--- a/frontend/src/routes/router.test.js
+++ b/frontend/src/routes/router.test.js
@@ -66,11 +66,11 @@ describe('router', () => {
 
       describe('send', () => {
         it('requires authorization', () => {
-          expect(routes.find((r) => r.path === '/send').meta.requiresAuth).toBeTruthy()
+          expect(routes.find((r) => r.path.startsWith('/send')).meta.requiresAuth).toBeTruthy()
         })
 
         it('loads the "Send" page', async () => {
-          const component = await routes.find((r) => r.path === '/send').component()
+          const component = await routes.find((r) => r.path.startsWith('/send')).component()
           expect(component.default.name).toBe('Send')
         })
       })
diff --git a/frontend/src/routes/routes.js b/frontend/src/routes/routes.js
index 8e5853021..869151618 100755
--- a/frontend/src/routes/routes.js
+++ b/frontend/src/routes/routes.js
@@ -19,7 +19,9 @@ const routes = [
     },
   },
   {
-    path: '/send',
+    // userIdentifier can be username, email or gradidoID
+    // communityIdentifier can be community name or community UUID
+    path: '/send/:communityIdentifier?/:userIdentifier?',
     component: () => import('@/pages/Send'),
     meta: {
       requiresAuth: true,
diff --git a/frontend/src/store/store.js b/frontend/src/store/store.js
index f11b27593..f56c8dcb5 100644
--- a/frontend/src/store/store.js
+++ b/frontend/src/store/store.js
@@ -58,6 +58,9 @@ export const mutations = {
   setDarkMode: (state, darkMode) => {
     state.darkMode = !!darkMode
   },
+  redirectPath: (state, redirectPath) => {
+    state.redirectPath = redirectPath || '/overview'
+  },
 }
 
 export const actions = {
@@ -89,6 +92,7 @@ export const actions = {
     commit('hideAmountGDT', true)
     commit('email', '')
     commit('setDarkMode', false)
+    commit('redirectPath', '/overview')
     localStorage.clear()
   },
 }
@@ -119,6 +123,7 @@ try {
       hideAmountGDT: null,
       email: '',
       darkMode: false,
+      redirectPath: '/overview',
     },
     getters: {},
     // Syncronous mutation of the state
diff --git a/frontend/src/store/store.test.js b/frontend/src/store/store.test.js
index 6a765cc3f..c6b3d88ab 100644
--- a/frontend/src/store/store.test.js
+++ b/frontend/src/store/store.test.js
@@ -264,7 +264,7 @@ describe('Vuex store', () => {
 
       it('calls twelve commits', () => {
         logout({ commit, state })
-        expect(commit).toHaveBeenCalledTimes(13)
+        expect(commit).toHaveBeenCalledTimes(14)
       })
 
       it('commits token', () => {