diff --git a/examples/mongo-demo/package.json b/examples/mongo-demo/package.json
index 2141bf20ea..e3e2852b4b 100644
--- a/examples/mongo-demo/package.json
+++ b/examples/mongo-demo/package.json
@@ -25,6 +25,7 @@
     "@prisma-next/mongo-pipeline-builder": "workspace:*",
     "@prisma-next/mongo-query-ast": "workspace:*",
     "@prisma-next/mongo-runtime": "workspace:*",
+    "@prisma-next/utils": "workspace:*",
     "mongodb": "catalog:",
     "react": "^19.2.4",
     "react-dom": "^19.2.4"
diff --git a/examples/mongo-demo/src/server.ts b/examples/mongo-demo/src/server.ts
index cafe261c63..4764a50b71 100644
--- a/examples/mongo-demo/src/server.ts
+++ b/examples/mongo-demo/src/server.ts
@@ -1,6 +1,6 @@
 import { existsSync } from 'node:fs';
 import { createServer, type ServerResponse } from 'node:http';
-import type { SimplifyDeep } from '@prisma-next/mongo-orm';
+import type { SimplifyDeep } from '@prisma-next/utils/simplify-deep';
 
 if (existsSync('.env')) {
   process.loadEnvFile('.env');
diff --git a/packages/1-framework/0-foundation/utils/package.json b/packages/1-framework/0-foundation/utils/package.json
index 835914e944..80198028e8 100644
--- a/packages/1-framework/0-foundation/utils/package.json
+++ b/packages/1-framework/0-foundation/utils/package.json
@@ -33,6 +33,7 @@
     "./defined": "./dist/defined.mjs",
     "./redact-db-url": "./dist/redact-db-url.mjs",
     "./result": "./dist/result.mjs",
+    "./simplify-deep": "./dist/simplify-deep.mjs",
     "./package.json": "./package.json"
   },
   "repository": {
diff --git a/packages/1-framework/0-foundation/utils/src/exports/simplify-deep.ts b/packages/1-framework/0-foundation/utils/src/exports/simplify-deep.ts
new file mode 100644
index 0000000000..7e2a030359
--- /dev/null
+++ b/packages/1-framework/0-foundation/utils/src/exports/simplify-deep.ts
@@ -0,0 +1 @@
+export type { SimplifyDeep } from '../simplify-deep';
diff --git a/packages/1-framework/0-foundation/utils/src/simplify-deep.ts b/packages/1-framework/0-foundation/utils/src/simplify-deep.ts
new file mode 100644
index 0000000000..ad1c84283f
--- /dev/null
+++ b/packages/1-framework/0-foundation/utils/src/simplify-deep.ts
@@ -0,0 +1,18 @@
+export type SimplifyDeep<T> = T extends readonly (infer Element)[]
+  ? T extends unknown[]
+    ? SimplifyDeep<Element>[]
+    : readonly SimplifyDeep<Element>[]
+  : T extends
+        | string
+        | number
+        | boolean
+        | bigint
+        | symbol
+        | Date
+        | RegExp
+        | Uint8Array
+        | ((...args: never[]) => unknown)
+    ? T
+    : T extends object
+      ? { [K in keyof T]: SimplifyDeep<T[K]> }
+      : T;
diff --git a/packages/1-framework/0-foundation/utils/test/simplify-deep.test-d.ts b/packages/1-framework/0-foundation/utils/test/simplify-deep.test-d.ts
new file mode 100644
index 0000000000..0ad91beadc
--- /dev/null
+++ b/packages/1-framework/0-foundation/utils/test/simplify-deep.test-d.ts
@@ -0,0 +1,80 @@
+import { describe, expectTypeOf, test } from 'vitest';
+import type { SimplifyDeep } from '../src/simplify-deep';
+
+describe('SimplifyDeep', () => {
+  test('primitives pass through', () => {
+    expectTypeOf<SimplifyDeep<string>>().toEqualTypeOf<string>();
+    expectTypeOf<SimplifyDeep<number>>().toEqualTypeOf<number>();
+    expectTypeOf<SimplifyDeep<boolean>>().toEqualTypeOf<boolean>();
+    expectTypeOf<SimplifyDeep<bigint>>().toEqualTypeOf<bigint>();
+    expectTypeOf<SimplifyDeep<symbol>>().toEqualTypeOf<symbol>();
+    expectTypeOf<SimplifyDeep<null>>().toEqualTypeOf<null>();
+    expectTypeOf<SimplifyDeep<undefined>>().toEqualTypeOf<undefined>();
+    expectTypeOf<SimplifyDeep<unknown>>().toEqualTypeOf<unknown>();
+    expectTypeOf<SimplifyDeep<never>>().toEqualTypeOf<never>();
+  });
+
+  test('branded primitives pass through', () => {
+    type Branded = string & { readonly __brand: true };
+    expectTypeOf<SimplifyDeep<Branded>>().toEqualTypeOf<Branded>();
+  });
+
+  test('Date, RegExp, and Uint8Array preserved', () => {
+    expectTypeOf<SimplifyDeep<Date>>().toEqualTypeOf<Date>();
+    expectTypeOf<SimplifyDeep<RegExp>>().toEqualTypeOf<RegExp>();
+    expectTypeOf<SimplifyDeep<Uint8Array>>().toEqualTypeOf<Uint8Array>();
+  });
+
+  test('functions preserved', () => {
+    type Fn = (a: number, b: string) => boolean;
+    expectTypeOf<SimplifyDeep<Fn>>().toEqualTypeOf<Fn>();
+  });
+
+  test('intersections flatten into plain objects', () => {
+    type Input = { a: number } & { b: string };
+    type Expected = { a: number; b: string };
+    expectTypeOf<SimplifyDeep<Input>>().toEqualTypeOf<Expected>();
+  });
+
+  test('mutable arrays recurse', () => {
+    type Input = ({ a: number } & { b: string })[];
+    type Expected = { a: number; b: string }[];
+    expectTypeOf<SimplifyDeep<Input>>().toEqualTypeOf<Expected>();
+  });
+
+  test('readonly arrays preserve readonly', () => {
+    type Input = readonly ({ a: number } & { b: string })[];
+    type Expected = readonly { a: number; b: string }[];
+    expectTypeOf<SimplifyDeep<Input>>().toEqualTypeOf<Expected>();
+  });
+
+  test('nested objects recurse', () => {
+    type Input = { nested: { a: number } & { b: string } };
+    type Expected = { nested: { a: number; b: string } };
+    expectTypeOf<SimplifyDeep<Input>>().toEqualTypeOf<Expected>();
+  });
+
+  test('nullable objects', () => {
+    type Input = ({ a: number } & { b: string }) | null;
+    type Expected = { a: number; b: string } | null;
+    expectTypeOf<SimplifyDeep<Input>>().toEqualTypeOf<Expected>();
+  });
+
+  test('nested arrays of intersected objects', () => {
+    type Input = {
+      items: ({ id: number } & { name: string })[];
+    };
+    type Expected = {
+      items: { id: number; name: string }[];
+    };
+    expectTypeOf<SimplifyDeep<Input>>().toEqualTypeOf<Expected>();
+  });
+
+  test('bidirectional assignability for concrete types', () => {
+    type Original = { a: number } & { b: string; nested: { c: boolean } & { d: number } };
+    type Simplified = SimplifyDeep<Original>;
+
+    expectTypeOf<Original>().toExtend<Simplified>();
+    expectTypeOf<Simplified>().toExtend<Original>();
+  });
+});
diff --git a/packages/1-framework/0-foundation/utils/tsdown.config.ts b/packages/1-framework/0-foundation/utils/tsdown.config.ts
index 141a29e845..d5f8138889 100644
--- a/packages/1-framework/0-foundation/utils/tsdown.config.ts
+++ b/packages/1-framework/0-foundation/utils/tsdown.config.ts
@@ -8,5 +8,6 @@ export default defineConfig({
     'src/exports/defined.ts',
     'src/exports/result.ts',
     'src/exports/redact-db-url.ts',
+    'src/exports/simplify-deep.ts',
   ],
 });
diff --git a/packages/1-framework/0-foundation/utils/vitest.config.ts b/packages/1-framework/0-foundation/utils/vitest.config.ts
index cb29ab9f30..9392f4a6c6 100644
--- a/packages/1-framework/0-foundation/utils/vitest.config.ts
+++ b/packages/1-framework/0-foundation/utils/vitest.config.ts
@@ -5,6 +5,10 @@ export default defineConfig({
     globals: true,
     environment: 'node',
     include: ['test/**/*.test.ts'],
+    typecheck: {
+      enabled: true,
+      include: ['test/**/*.test-d.ts'],
+    },
     coverage: {
       provider: 'v8',
       reporter: ['text', 'lcov'],
diff --git a/packages/2-mongo-family/5-query-builders/orm/package.json b/packages/2-mongo-family/5-query-builders/orm/package.json
index 6d0eb76f7d..0366587cfe 100644
--- a/packages/2-mongo-family/5-query-builders/orm/package.json
+++ b/packages/2-mongo-family/5-query-builders/orm/package.json
@@ -16,10 +16,11 @@
   },
   "dependencies": {
     "@prisma-next/contract": "workspace:*",
+    "@prisma-next/framework-components": "workspace:*",
     "@prisma-next/mongo-contract": "workspace:*",
     "@prisma-next/mongo-query-ast": "workspace:*",
-    "@prisma-next/framework-components": "workspace:*",
-    "@prisma-next/mongo-value": "workspace:*"
+    "@prisma-next/mongo-value": "workspace:*",
+    "@prisma-next/utils": "workspace:*"
   },
   "devDependencies": {
     "@prisma-next/adapter-mongo": "workspace:*",
diff --git a/packages/2-mongo-family/5-query-builders/orm/src/exports/index.ts b/packages/2-mongo-family/5-query-builders/orm/src/exports/index.ts
index e4d287db32..38b120f569 100644
--- a/packages/2-mongo-family/5-query-builders/orm/src/exports/index.ts
+++ b/packages/2-mongo-family/5-query-builders/orm/src/exports/index.ts
@@ -1,3 +1,4 @@
+export type { SimplifyDeep } from '@prisma-next/utils/simplify-deep';
 export type { MongoCollection } from '../collection';
 export { createMongoCollection } from '../collection';
 export { compileMongoQuery } from '../compile';
@@ -27,7 +28,6 @@ export type {
   MongoWhereFilter,
   NoIncludes,
   ResolvedCreateInput,
-  SimplifyDeep,
   VariantCreateInput,
   VariantModelRow,
   VariantNames,
diff --git a/packages/2-mongo-family/5-query-builders/orm/src/types.ts b/packages/2-mongo-family/5-query-builders/orm/src/types.ts
index 95e360dde2..692d9299dd 100644
--- a/packages/2-mongo-family/5-query-builders/orm/src/types.ts
+++ b/packages/2-mongo-family/5-query-builders/orm/src/types.ts
@@ -11,16 +11,6 @@ import type {
 
 type Simplify<T> = T extends unknown ? { [K in keyof T]: T[K] } : never;
 
-export type SimplifyDeep<T> = T extends readonly (infer E)[]
-  ? SimplifyDeep<E>[]
-  : T extends Date | RegExp | ((...args: never[]) => unknown)
-    ? T
-    : T extends object
-      ? T extends unknown
-        ? { [K in keyof T]: SimplifyDeep<T[K]> }
-        : never
-      : T;
-
 type ModelRelations<
   TContract extends MongoContract,
   ModelName extends string & keyof TContract['models'],
diff --git a/packages/3-extensions/sql-orm-client/src/collection.ts b/packages/3-extensions/sql-orm-client/src/collection.ts
index fc3b29ff68..3173e4c000 100644
--- a/packages/3-extensions/sql-orm-client/src/collection.ts
+++ b/packages/3-extensions/sql-orm-client/src/collection.ts
@@ -10,6 +10,7 @@ import {
   type ToWhereExpr,
   type WhereArg,
 } from '@prisma-next/sql-relational-core/ast';
+import type { SimplifyDeep } from '@prisma-next/utils/simplify-deep';
 import { createAggregateBuilder, isAggregateSelector } from './aggregate-builder';
 import { normalizeAggregateResult } from './collection-aggregate-result';
 import { mapCursorValuesToColumns, mapFieldsToColumns } from './collection-column-mapping';
@@ -159,7 +160,7 @@ interface MtiCreateContext {
 export class Collection<
   TContract extends Contract<SqlStorage>,
   ModelName extends string,
-  Row = InferRootRow<TContract, ModelName>,
+  Row = SimplifyDeep<InferRootRow<TContract, ModelName>>,
   State extends CollectionTypeState = DefaultCollectionTypeState,
 > implements RowSelection<Row>
 {
@@ -317,15 +318,17 @@ export class Collection<
   ): Collection<
     TContract,
     ModelName,
-    Row & {
-      [K in RelName]: IncludeRefinementValue<
-        TContract,
-        ModelName,
-        K,
-        DefaultModelRow<TContract, RelatedName>,
-        RefinedResult
-      >;
-    },
+    SimplifyDeep<
+      Row & {
+        [K in RelName]: IncludeRefinementValue<
+          TContract,
+          ModelName,
+          K,
+          DefaultModelRow<TContract, RelatedName>,
+          RefinedResult
+        >;
+      }
+    >,
     State
   > {
     const relation = resolveIncludeRelation(this.contract, this.modelName, relationName as string);
@@ -391,15 +394,17 @@ export class Collection<
     };
 
     return this.#cloneWithRow<
-      Row & {
-        [K in RelName]: IncludeRefinementValue<
-          TContract,
-          ModelName,
-          K,
-          DefaultModelRow<TContract, RelatedName>,
-          RefinedResult
-        >;
-      },
+      SimplifyDeep<
+        Row & {
+          [K in RelName]: IncludeRefinementValue<
+            TContract,
+            ModelName,
+            K,
+            DefaultModelRow<TContract, RelatedName>,
+            RefinedResult
+          >;
+        }
+      >,
       State
     >({
       includes: [...this.state.includes, includeExpr],
@@ -416,15 +421,19 @@ export class Collection<
   ): Collection<
     TContract,
     ModelName,
-    Pick<DefaultModelRow<TContract, ModelName>, Fields[number]> &
-      IncludedRelationsForRow<TContract, ModelName, Row>,
+    SimplifyDeep<
+      Pick<DefaultModelRow<TContract, ModelName>, Fields[number]> &
+        IncludedRelationsForRow<TContract, ModelName, Row>
+    >,
     State
   > {
     const selectedFields = mapFieldsToColumns(this.contract, this.modelName, fields);
 
     return this.#cloneWithRow<
-      Pick<DefaultModelRow<TContract, ModelName>, Fields[number]> &
-        IncludedRelationsForRow<TContract, ModelName, Row>,
+      SimplifyDeep<
+        Pick<DefaultModelRow<TContract, ModelName>, Fields[number]> &
+          IncludedRelationsForRow<TContract, ModelName, Row>
+      >,
       State
     >({
       selectedFields,
diff --git a/packages/3-extensions/sql-orm-client/src/grouped-collection.ts b/packages/3-extensions/sql-orm-client/src/grouped-collection.ts
index 4a23e5667c..d594ad6e8c 100644
--- a/packages/3-extensions/sql-orm-client/src/grouped-collection.ts
+++ b/packages/3-extensions/sql-orm-client/src/grouped-collection.ts
@@ -8,6 +8,7 @@ import {
   ColumnRef,
   LiteralExpr,
 } from '@prisma-next/sql-relational-core/ast';
+import type { SimplifyDeep } from '@prisma-next/utils/simplify-deep';
 import { createAggregateBuilder, isAggregateSelector } from './aggregate-builder';
 import { getFieldToColumnMap } from './collection-contract';
 import { mapStorageRowToModelFields } from './collection-runtime';
@@ -84,7 +85,11 @@ export class GroupedCollection<
   async aggregate<Spec extends AggregateSpec>(
     fn: (aggregate: AggregateBuilder<TContract, ModelName>) => Spec,
   ): Promise<
-    Array<Pick<DefaultModelRow<TContract, ModelName>, GroupFields[number]> & AggregateResult<Spec>>
+    Array<
+      SimplifyDeep<
+        Pick<DefaultModelRow<TContract, ModelName>, GroupFields[number]> & AggregateResult<Spec>
+      >
+    >
   > {
     const aggregateSpec = fn(createAggregateBuilder(this.contract, this.modelName));
     const aggregateEntries = Object.entries(aggregateSpec);
@@ -118,7 +123,9 @@ export class GroupedCollection<
       }
       return mapped;
     }) as Array<
-      Pick<DefaultModelRow<TContract, ModelName>, GroupFields[number]> & AggregateResult<Spec>
+      SimplifyDeep<
+        Pick<DefaultModelRow<TContract, ModelName>, GroupFields[number]> & AggregateResult<Spec>
+      >
     >;
   }
 }
diff --git a/packages/3-extensions/sql-orm-client/test/simplify-deep.test-d.ts b/packages/3-extensions/sql-orm-client/test/simplify-deep.test-d.ts
new file mode 100644
index 0000000000..b3ea919d0e
--- /dev/null
+++ b/packages/3-extensions/sql-orm-client/test/simplify-deep.test-d.ts
@@ -0,0 +1,134 @@
+import { describe, expectTypeOf, test } from 'vitest';
+import { Collection } from '../src/collection';
+import { createMockRuntime, getTestContext } from './helpers';
+
+describe('Collection result types are simplified', () => {
+  const runtime = createMockRuntime();
+  const context = getTestContext();
+
+  test('default Row is a plain object', () => {
+    const users = new Collection({ runtime, context }, 'User');
+    type UserRow = Awaited<ReturnType<typeof users.first>>;
+    expectTypeOf<NonNullable<UserRow>>().toEqualTypeOf<{
+      id: number;
+      name: string;
+      email: string;
+      invitedById: number | null;
+      address: {
+        readonly street: string;
+        readonly city: string;
+        readonly zip: string | null;
+      } | null;
+    }>();
+  });
+
+  test('select() produces a plain object', () => {
+    const users = new Collection({ runtime, context }, 'User');
+    const selected = users.select('id', 'email');
+    type SelectedRow = Awaited<ReturnType<typeof selected.first>>;
+    expectTypeOf<NonNullable<SelectedRow>>().toEqualTypeOf<{
+      id: number;
+      email: string;
+    }>();
+  });
+
+  test('include() produces a plain object with nested relation', () => {
+    const users = new Collection({ runtime, context }, 'User');
+    const withPosts = users.include('posts');
+    type WithPostsRow = Awaited<ReturnType<typeof withPosts.first>>;
+    expectTypeOf<NonNullable<WithPostsRow>>().toEqualTypeOf<{
+      id: number;
+      name: string;
+      email: string;
+      invitedById: number | null;
+      address: {
+        readonly street: string;
+        readonly city: string;
+        readonly zip: string | null;
+      } | null;
+      posts: {
+        id: number;
+        title: string;
+        userId: number;
+        views: number;
+        embedding: number[] | null;
+      }[];
+    }>();
+  });
+
+  test('select().include() produces a plain object', () => {
+    const users = new Collection({ runtime, context }, 'User');
+    const selected = users.select('name').include('posts');
+    type Row = Awaited<ReturnType<typeof selected.first>>;
+    expectTypeOf<NonNullable<Row>>().toEqualTypeOf<{
+      name: string;
+      posts: {
+        id: number;
+        title: string;
+        userId: number;
+        views: number;
+        embedding: number[] | null;
+      }[];
+    }>();
+  });
+
+  test('include() with non-nullable to-one relation', () => {
+    const posts = new Collection({ runtime, context }, 'Post');
+    const withAuthor = posts.include('author');
+    type Row = Awaited<ReturnType<typeof withAuthor.first>>;
+    type AuthorField = NonNullable<Row>['author'];
+    expectTypeOf<AuthorField>().toEqualTypeOf<{
+      id: number;
+      name: string;
+      email: string;
+      invitedById: number | null;
+      address: {
+        readonly street: string;
+        readonly city: string;
+        readonly zip: string | null;
+      } | null;
+    }>();
+  });
+
+  test('chained include() produces a plain object', () => {
+    const users = new Collection({ runtime, context }, 'User');
+    const withPostsAndInviter = users.include('posts').include('invitedBy');
+    type Row = Awaited<ReturnType<typeof withPostsAndInviter.first>>;
+    expectTypeOf<NonNullable<Row>>().toEqualTypeOf<{
+      id: number;
+      name: string;
+      email: string;
+      invitedById: number | null;
+      address: {
+        readonly street: string;
+        readonly city: string;
+        readonly zip: string | null;
+      } | null;
+      posts: {
+        id: number;
+        title: string;
+        userId: number;
+        views: number;
+        embedding: number[] | null;
+      }[];
+      invitedBy: {
+        id: number;
+        name: string;
+        email: string;
+        invitedById: number | null;
+        address: {
+          readonly street: string;
+          readonly city: string;
+          readonly zip: string | null;
+        } | null;
+      } | null;
+    }>();
+  });
+
+  test('include() with count refinement', () => {
+    const users = new Collection({ runtime, context }, 'User');
+    const withPostCount = users.include('posts', (posts) => posts.count());
+    type Row = Awaited<ReturnType<typeof withPostCount.first>>;
+    expectTypeOf<NonNullable<Row>['posts']>().toEqualTypeOf<number>();
+  });
+});
diff --git a/pnpm-lock.yaml b/pnpm-lock.yaml
index dd6e78b8b4..6ff5005dd0 100644
--- a/pnpm-lock.yaml
+++ b/pnpm-lock.yaml
@@ -124,6 +124,9 @@ importers:
       '@prisma-next/mongo-runtime':
         specifier: workspace:*
         version: link:../../packages/2-mongo-family/7-runtime
+      '@prisma-next/utils':
+        specifier: workspace:*
+        version: link:../../packages/1-framework/0-foundation/utils
       mongodb:
         specifier: 'catalog:'
         version: 6.21.0
@@ -1192,6 +1195,9 @@ importers:
       '@prisma-next/mongo-value':
         specifier: workspace:*
         version: link:../../1-foundation/mongo-value
+      '@prisma-next/utils':
+        specifier: workspace:*
+        version: link:../../../1-framework/0-foundation/utils
     devDependencies:
       '@prisma-next/adapter-mongo':
         specifier: workspace:*