diff --git a/server/src/internal/api/check/handleCheck.ts b/server/src/internal/api/check/handleCheck.ts
index 36bbcfa43..800f64cc2 100644
--- a/server/src/internal/api/check/handleCheck.ts
+++ b/server/src/internal/api/check/handleCheck.ts
@@ -77,7 +77,24 @@ export const handleCheck = createRoute({
 				flag: null,
 			});
 
-			return c.json(fallbackResponse);
+			const featureToUse = ctx.features.find(
+				(feature) => feature.id === body.feature_id,
+			);
+
+			const transformedFallbackResponse = featureToUse
+				? applyResponseVersionChanges<CheckResponseV3>({
+						input: fallbackResponse,
+						targetVersion: ctx.apiVersion,
+						resource: AffectedResource.Check,
+						legacyData: {
+							noCusEnts: false,
+							featureToUse,
+						},
+						ctx,
+					})
+				: fallbackResponse;
+
+			return c.json(transformedFallbackResponse);
 		}
 
 		let response: CheckResponseV3;
diff --git a/server/tests/integration/balances/check/check-fallback.test.ts b/server/tests/integration/balances/check/check-fallback.test.ts
index 6b73c5796..913d10790 100644
--- a/server/tests/integration/balances/check/check-fallback.test.ts
+++ b/server/tests/integration/balances/check/check-fallback.test.ts
@@ -64,3 +64,58 @@ test(`${chalk.yellowBright("check-fallback: /check returns allowed=true on retry
 		CusService.getFull = originalGetFull;
 	}
 }, 20000);
+
+test(`${chalk.yellowBright("check-fallback-legacy: /check fallback applies response version transforms")}`, async () => {
+	const messagesItem = items.monthlyMessages({ includedUsage: 1000 });
+	const freeProd = products.base({
+		id: "check-fallback-legacy-free",
+		items: [messagesItem],
+	});
+
+	const { customerId } = await initScenario({
+		customerId: "check-fallback-legacy",
+		setup: [s.customer({ testClock: false }), s.products({ list: [freeProd] })],
+		actions: [s.attach({ productId: freeProd.id })],
+	});
+
+	const originalGetFull = CusService.getFull;
+	const app = createHonoApp();
+
+	try {
+		CusService.getFull = (async () => {
+			const error = new Error("simulated db outage") as Error & {
+				code: string;
+			};
+			error.code = "CONNECT_TIMEOUT";
+			throw error;
+		}) as typeof CusService.getFull;
+
+		const response = await app.fetch(
+			new Request("http://localhost/v1/balances.check", {
+				method: "POST",
+				headers: {
+					Authorization: `Bearer ${process.env.UNIT_TEST_AUTUMN_SECRET_KEY || ""}`,
+					"Content-Type": "application/json",
+					"x-api-version": ApiVersion.V1_Beta.toString(),
+					"x-skip-cache": "true",
+				},
+				body: JSON.stringify({
+					customer_id: customerId,
+					feature_id: TestFeature.Messages,
+				}),
+			}),
+		);
+
+		expect(response.status).toBe(200);
+		expect(await response.json()).toEqual({
+			allowed: false,
+			code: "feature_found",
+			customer_id: customerId,
+			feature_id: TestFeature.Messages,
+			entity_id: undefined,
+			required_balance: 1,
+		});
+	} finally {
+		CusService.getFull = originalGetFull;
+	}
+}, 20000);