diff --git a/src/hooks/runtime-fallback/constants.ts b/src/hooks/runtime-fallback/constants.ts
index 3f011b333..3bd4409a4 100644
--- a/src/hooks/runtime-fallback/constants.ts
+++ b/src/hooks/runtime-fallback/constants.ts
@@ -11,7 +11,7 @@ import type { RuntimeFallbackConfig } from "../../config"
  */
 export const DEFAULT_CONFIG: Required<RuntimeFallbackConfig> = {
   enabled: false,
-  retry_on_errors: [429, 500, 502, 503, 504],
+  retry_on_errors: [402, 429, 500, 502, 503, 504],
   max_fallback_attempts: 3,
   cooldown_seconds: 60,
   timeout_seconds: 30,
@@ -37,6 +37,11 @@ export const RETRYABLE_ERROR_PATTERNS = [
   /try.?again/i,
   /credit.*balance.*too.*low/i,
   /insufficient.?(?:credits?|funds?|balance)/i,
+  /subscription.*quota/i,
+  /billing.?(?:hard.?)?limit/i,
+  /payment.?required/i,
+  /out\s+of\s+credits?/i,
+  /(?:^|\s)402(?:\s|$)/,
   /(?:^|\s)429(?:\s|$)/,
   /(?:^|\s)503(?:\s|$)/,
   /(?:^|\s)529(?:\s|$)/,
diff --git a/src/hooks/runtime-fallback/error-classifier.test.ts b/src/hooks/runtime-fallback/error-classifier.test.ts
index 954e28758..63e38733e 100644
--- a/src/hooks/runtime-fallback/error-classifier.test.ts
+++ b/src/hooks/runtime-fallback/error-classifier.test.ts
@@ -166,3 +166,100 @@ describe("extractStatusCode", () => {
     expect(extractStatusCode(error)).toBe(400)
   })
 })
+
+describe("quota error detection (fixes #2747)", () => {
+  test("classifies prettified subscription quota error as quota_exceeded", () => {
+    //#given
+    const error = {
+      name: "AI_APICallError",
+      message: "Subscription quota exceeded. You can continue using free models.",
+    }
+
+    //#when
+    const errorType = classifyErrorType(error)
+    const retryable = isRetryableError(error, [402, 429, 500, 502, 503, 504])
+
+    //#then
+    expect(errorType).toBe("quota_exceeded")
+    expect(retryable).toBe(true)
+  })
+
+  test("classifies billing hard limit error as quota_exceeded", () => {
+    //#given
+    const error = { message: "You have reached your billing hard limit." }
+
+    //#when
+    const errorType = classifyErrorType(error)
+
+    //#then
+    expect(errorType).toBe("quota_exceeded")
+  })
+
+  test("classifies exhausted capacity error as quota_exceeded", () => {
+    //#given
+    const error = { message: "You have exhausted your capacity on this model." }
+
+    //#when
+    const errorType = classifyErrorType(error)
+
+    //#then
+    expect(errorType).toBe("quota_exceeded")
+  })
+
+  test("classifies out of credits error as quota_exceeded", () => {
+    //#given
+    const error = { message: "Out of credits. Please add more credits to continue." }
+
+    //#when
+    const errorType = classifyErrorType(error)
+
+    //#then
+    expect(errorType).toBe("quota_exceeded")
+  })
+
+  test("treats HTTP 402 Payment Required as retryable", () => {
+    //#given
+    const error = { statusCode: 402, message: "Payment Required" }
+
+    //#when
+    const retryable = isRetryableError(error, [402, 429, 500, 502, 503, 504])
+
+    //#then
+    expect(retryable).toBe(true)
+  })
+
+  test("matches subscription quota pattern in RETRYABLE_ERROR_PATTERNS", () => {
+    //#given
+    const error = { message: "Subscription quota exceeded. You can continue using free models." }
+
+    //#when
+    const retryable = isRetryableError(error, [429, 503])
+
+    //#then
+    expect(retryable).toBe(true)
+  })
+
+  test("classifies QuotaExceededError by errorName even without quota keywords in message", () => {
+    //#given
+    const error = { name: "QuotaExceededError", message: "Request failed." }
+
+    //#when
+    const errorType = classifyErrorType(error)
+
+    //#then
+    expect(errorType).toBe("quota_exceeded")
+  })
+
+  test("detects payment required errors as retryable", () => {
+    //#given
+    const error = { message: "Error 402: payment required for this request" }
+
+    //#when
+    const errorType = classifyErrorType(error)
+    const retryable = isRetryableError(error, [429, 503])
+
+    //#then
+    expect(errorType).toBe("quota_exceeded")
+    expect(retryable).toBe(true)
+  })
+})
diff --git a/src/hooks/runtime-fallback/error-classifier.ts b/src/hooks/runtime-fallback/error-classifier.ts
index e581f3fb8..088735edd 100644
--- a/src/hooks/runtime-fallback/error-classifier.ts
+++ b/src/hooks/runtime-fallback/error-classifier.ts
@@ -21,6 +21,13 @@ export function getErrorMessage(error: unknown): string {
     }
   }
 
+  const errorObj2 = error as Record<string, unknown>
+  const name = errorObj2.name
+  if (typeof name === "string" && name.length > 0) {
+    const nameColonMatch = name.match(/:\s*(.+)/)
+    if (nameColonMatch) return nameColonMatch[1].trim().toLowerCase()
+  }
+
   try {
     return JSON.stringify(error).toLowerCase()
   } catch {
@@ -112,6 +119,21 @@ export function classifyErrorType(error: unknown): string | undefined {
     return "model_not_found"
   }
 
+  if (
+    errorName?.includes("quotaexceeded") ||
+    errorName?.includes("insufficientquota") ||
+    errorName?.includes("billingerror") ||
+    /quota.?exceeded/i.test(message) ||
+    /subscription.*quota/i.test(message) ||
+    /insufficient.?quota/i.test(message) ||
+    /billing.?(?:hard.?)?limit/i.test(message) ||
+    /exhausted\s+your\s+capacity/i.test(message) ||
+    /out\s+of\s+credits?/i.test(message) ||
+    /payment.?required/i.test(message)
+  ) {
+    return "quota_exceeded"
+  }
+
   return undefined
 }
 
@@ -181,6 +203,10 @@ export function isRetryableError(error: unknown, retryOnErrors: number[]): boole
     return true
   }
 
+  if (errorType === "quota_exceeded") {
+    return true
+  }
+
   if (statusCode && retryOnErrors.includes(statusCode)) {
     return true
   }