diff --git a/packages/repository-tests/src/crud/create-retrieve.suite.ts b/packages/repository-tests/src/crud/create-retrieve.suite.ts
index 7ec364f8b6d6..ac8706a7e657 100644
--- a/packages/repository-tests/src/crud/create-retrieve.suite.ts
+++ b/packages/repository-tests/src/crud/create-retrieve.suite.ts
@@ -12,6 +12,7 @@ import {
   property,
 } from '@loopback/repository';
 import {expect, toJSON} from '@loopback/testlab';
+import {MixedIdType} from '../helpers.repository-tests';
 import {
   deleteAllModelsInDefaultDataSource,
   withCrudCtx,
@@ -38,7 +39,7 @@ export function createRetrieveSuite(
       generated: true,
       description: 'The unique identifier for a product',
     })
-    id: number | string;
+    id: MixedIdType;
 
     @property({type: 'string', required: true})
     name: string;
diff --git a/packages/repository-tests/src/crud/freeform-properties.suite.ts b/packages/repository-tests/src/crud/freeform-properties.suite.ts
index 0495eefb73d2..7503dbc3f701 100644
--- a/packages/repository-tests/src/crud/freeform-properties.suite.ts
+++ b/packages/repository-tests/src/crud/freeform-properties.suite.ts
@@ -7,6 +7,7 @@ import {Entity, model, property} from '@loopback/repository';
 import {EntityCrudRepository} from '@loopback/repository';
 import {expect, skipIf, toJSON} from '@loopback/testlab';
 import {Suite} from 'mocha';
+import {MixedIdType} from '../helpers.repository-tests';
 import {
   withCrudCtx,
   deleteAllModelsInDefaultDataSource,
@@ -37,7 +38,7 @@ export function freeformPropertiesSuite(
           id: true,
           description: 'The unique identifier for a product',
         })
-        id: number | string;
+        id: MixedIdType;
 
         @property({type: 'string', required: true})
         name: string;
diff --git a/packages/repository-tests/src/crud/replace-by-id.suite.ts b/packages/repository-tests/src/crud/replace-by-id.suite.ts
index a2e2d0d222f1..3bf0d64ec5f3 100644
--- a/packages/repository-tests/src/crud/replace-by-id.suite.ts
+++ b/packages/repository-tests/src/crud/replace-by-id.suite.ts
@@ -6,6 +6,7 @@
 import {Entity, model, property} from '@loopback/repository';
 import {AnyObject, EntityCrudRepository} from '@loopback/repository';
 import {expect, toJSON} from '@loopback/testlab';
+import {MixedIdType} from '../helpers.repository-tests';
 import {
   deleteAllModelsInDefaultDataSource,
   withCrudCtx,
@@ -31,7 +32,7 @@ export function createSuiteForReplaceById(
       generated: true,
       description: 'The unique identifier for a product',
     })
-    id: number | string;
+    id: MixedIdType;
 
     @property({type: 'string', required: true})
     name: string;
diff --git a/packages/repository-tests/src/crud/transactions.suite.ts b/packages/repository-tests/src/crud/transactions.suite.ts
index 73bc79dd1f24..87a0492c26a7 100644
--- a/packages/repository-tests/src/crud/transactions.suite.ts
+++ b/packages/repository-tests/src/crud/transactions.suite.ts
@@ -14,7 +14,7 @@ import {
 } from '@loopback/repository';
 import {expect, skipIf, toJSON} from '@loopback/testlab';
 import {Suite} from 'mocha';
-import {withCrudCtx} from '../helpers.repository-tests';
+import {withCrudCtx, MixedIdType} from '../helpers.repository-tests';
 import {
   CrudFeatures,
   CrudTestContext,
@@ -42,7 +42,7 @@ export function transactionSuite(
           generated: true,
           description: 'The unique identifier for a product',
         })
-        id: number | string;
+        id: MixedIdType;
 
         @property({type: 'string', required: true})
         name: string;