diff --git a/.changeset/smooth-pianos-argue.md b/.changeset/smooth-pianos-argue.md
new file mode 100644
index 0000000000..5ab8be8136
--- /dev/null
+++ b/.changeset/smooth-pianos-argue.md
@@ -0,0 +1,5 @@
+---
+'@backstage/backend-test-utils': patch
+---
+
+Updated `ServiceFactoryTester` to only accept plain service factory objects, no longer supporting the callback form. This lines up with the changes to `@backstage/backend-plugin-api` and should not require any code changes.
diff --git a/packages/backend-test-utils/api-report.md b/packages/backend-test-utils/api-report.md
index 566ac5b888..d122e038a6 100644
--- a/packages/backend-test-utils/api-report.md
+++ b/packages/backend-test-utils/api-report.md
@@ -371,9 +371,7 @@ export namespace mockServices {
 // @public
 export class ServiceFactoryTester<TService, TScope extends 'root' | 'plugin'> {
   static from<TService, TScope extends 'root' | 'plugin'>(
-    subject:
-      | ServiceFactory<TService, TScope>
-      | (() => ServiceFactory<TService, TScope>),
+    subject: ServiceFactory<TService, TScope>,
     options?: ServiceFactoryTesterOptions,
   ): ServiceFactoryTester<TService, TScope>;
   get(
@@ -387,7 +385,7 @@ export class ServiceFactoryTester<TService, TScope extends 'root' | 'plugin'> {
 
 // @public
 export interface ServiceFactoryTesterOptions {
-  dependencies?: Array<ServiceFactory | (() => ServiceFactory)>;
+  dependencies?: Array<ServiceFactory>;
 }
 
 // @public (undocumented)
diff --git a/packages/backend-test-utils/src/next/wiring/ServiceFactoryTester.ts b/packages/backend-test-utils/src/next/wiring/ServiceFactoryTester.ts
index 0555ab10a4..9247a9132e 100644
--- a/packages/backend-test-utils/src/next/wiring/ServiceFactoryTester.ts
+++ b/packages/backend-test-utils/src/next/wiring/ServiceFactoryTester.ts
@@ -35,7 +35,7 @@ export interface ServiceFactoryTesterOptions {
    * If a service factory is provided for a service that already has a default
    * implementation, the provided factory will override the default.
    */
-  dependencies?: Array<ServiceFactory | (() => ServiceFactory)>;
+  dependencies?: Array<ServiceFactory>;
 }
 
 /**
@@ -55,20 +55,15 @@ export class ServiceFactoryTester<TService, TScope extends 'root' | 'plugin'> {
    * @returns A new tester instance for the provided subject.
    */
   static from<TService, TScope extends 'root' | 'plugin'>(
-    subject:
-      | ServiceFactory<TService, TScope>
-      | (() => ServiceFactory<TService, TScope>),
+    subject: ServiceFactory<TService, TScope>,
     options?: ServiceFactoryTesterOptions,
   ) {
-    const subjectFactory = typeof subject === 'function' ? subject() : subject;
     const registry = ServiceRegistry.create([
       ...defaultServiceFactories,
-      ...(options?.dependencies?.map(f =>
-        typeof f === 'function' ? f() : f,
-      ) ?? []),
-      subjectFactory,
+      ...(options?.dependencies ?? []),
+      subject,
     ]);
-    return new ServiceFactoryTester(subjectFactory.service, registry);
+    return new ServiceFactoryTester(subject.service, registry);
   }
 
   private constructor(