diff --git a/app/api/auth/magic-link/route.ts b/app/api/auth/magic-link/route.ts
index db0ee7f..8f734a5 100644
--- a/app/api/auth/magic-link/route.ts
+++ b/app/api/auth/magic-link/route.ts
@@ -4,6 +4,7 @@ import { NextRequest, NextResponse } from 'next/server'
 import { loginRateLimit } from '@/lib/utils/rate-limiter'
 
 export const maxDuration = 45
+const MAGIC_LINK_COOLDOWN_SECONDS = 60
 
 function isValidEmail(email: string) {
   const atIndex = email.lastIndexOf('@')
@@ -39,7 +40,8 @@ function normalizeSupabaseAuthError(error: { message?: string; status?: number }
   ) {
     return {
       status: 429,
-      message: 'A magic link was requested recently. Please wait 60 seconds before requesting another one.',
+      message: `A magic link was requested recently. Please wait ${MAGIC_LINK_COOLDOWN_SECONDS} seconds before requesting another one.`,
+      retryAfter: MAGIC_LINK_COOLDOWN_SECONDS,
     }
   }
 
@@ -47,12 +49,22 @@ function normalizeSupabaseAuthError(error: { message?: string; status?: number }
     return {
       status: 400,
       message: 'Please enter a valid email address.',
+      retryAfter: 0,
+    }
+  }
+
+  if (lowerMessage.includes('redirect')) {
+    return {
+      status: 500,
+      message: 'Magic link redirect is not configured correctly. Please contact support.',
+      retryAfter: 0,
     }
   }
 
   return {
-    status: 502,
-    message: 'Unable to send magic link right now. Please try again in a moment.',
+    status: 503,
+    message: 'Email delivery is temporarily unavailable. Please try again in a moment.',
+    retryAfter: MAGIC_LINK_COOLDOWN_SECONDS,
   }
 }
 
@@ -66,6 +78,10 @@ export async function POST(request: NextRequest) {
       return NextResponse.json(
         {
           error: 'Too many magic link requests. Please try again later.',
+          retryAfter: Math.max(
+            MAGIC_LINK_COOLDOWN_SECONDS,
+            Math.ceil(((rateLimitResult.lockedUntil || rateLimitResult.resetTime) - Date.now()) / 1000)
+          ),
           lockedUntil: rateLimitResult.lockedUntil,
           resetTime: rateLimitResult.resetTime,
         },
@@ -118,8 +134,16 @@ export async function POST(request: NextRequest) {
         durationMs: Date.now() - startedAt,
       })
       return NextResponse.json(
-        { error: normalizedError.message },
-        { status: normalizedError.status }
+        {
+          error: normalizedError.message,
+          retryAfter: normalizedError.retryAfter,
+        },
+        {
+          status: normalizedError.status,
+          headers: normalizedError.retryAfter
+            ? { 'Retry-After': String(normalizedError.retryAfter) }
+            : undefined,
+        }
       )
     }
 
diff --git a/app/login/page.tsx b/app/login/page.tsx
index eac75ae..93a7c28 100644
--- a/app/login/page.tsx
+++ b/app/login/page.tsx
@@ -32,6 +32,7 @@ const loginHighlights = [
 ]
 
 const workspaceItems = ["Project planning", "Collaborator review", "Security settings"]
+const MAGIC_LINK_COOLDOWN_SECONDS = 60
 
 function AuthBrand() {
   return (
@@ -56,6 +57,7 @@ function LoginPageContent() {
   const [success, setSuccess] = useState("")
   const [isLoading, setIsLoading] = useState(false)
   const [isCheckingAuth, setIsCheckingAuth] = useState(true)
+  const [cooldownSeconds, setCooldownSeconds] = useState(0)
   const [t, setT] = useState(getTranslations("en"))
 
   const checkAuth = useCallback(async () => {
@@ -80,11 +82,26 @@ function LoginPageContent() {
     void checkAuth()
   }, [checkAuth])
 
+  useEffect(() => {
+    if (cooldownSeconds <= 0) return
+
+    const timer = window.setInterval(() => {
+      setCooldownSeconds((current) => Math.max(0, current - 1))
+    }, 1000)
+
+    return () => window.clearInterval(timer)
+  }, [cooldownSeconds])
+
   const handleLogin = async (event: React.FormEvent) => {
     event.preventDefault()
     setError("")
     setSuccess("")
 
+    if (cooldownSeconds > 0) {
+      setError(`Please wait ${cooldownSeconds}s before requesting another magic link.`)
+      return
+    }
+
     if (!email) {
       setError(`${t.auth?.email || "Email"} is required`)
       return
@@ -102,8 +119,12 @@ function LoginPageContent() {
       const result = await signInWithOtp(email, rememberMe)
 
       if (result.success) {
+        setCooldownSeconds(MAGIC_LINK_COOLDOWN_SECONDS)
         setSuccess(result.message || "Check your email for the magic link to sign in.")
       } else {
+        if (result.retryAfter) {
+          setCooldownSeconds(result.retryAfter)
+        }
         setError(result.error || "Login failed")
       }
     } catch (err: unknown) {
@@ -256,7 +277,7 @@ function LoginPageContent() {
 
                 <Button
                   type="submit"
-                  disabled={isLoading || !!success}
+                  disabled={isLoading || !!success || cooldownSeconds > 0}
                   className="h-12 w-full rounded-lg text-sm font-semibold"
                 >
                   {isLoading ? (
@@ -264,6 +285,8 @@ function LoginPageContent() {
                       <ArrowPathIcon className="h-5 w-5 animate-spin" />
                       Sending...
                     </>
+                  ) : cooldownSeconds > 0 ? (
+                    <>Wait {cooldownSeconds}s</>
                   ) : (
                     <>
                       Send Magic Link
diff --git a/app/signup/page.tsx b/app/signup/page.tsx
index 8ed082b..1d6cc5b 100644
--- a/app/signup/page.tsx
+++ b/app/signup/page.tsx
@@ -34,6 +34,7 @@ const signupHighlights = [
 ]
 
 const previewItems = ["Plan", "Build", "Review"]
+const MAGIC_LINK_COOLDOWN_SECONDS = 60
 
 function AuthBrand() {
   return (
@@ -60,6 +61,7 @@ function SignUpPageContent() {
   const [isLoading, setIsLoading] = useState(false)
   const [isCheckingAuth, setIsCheckingAuth] = useState(true)
   const [usePassword, setUsePassword] = useState(false)
+  const [cooldownSeconds, setCooldownSeconds] = useState(0)
   const [t, setT] = useState(getTranslations("en"))
 
   const checkAuth = useCallback(async () => {
@@ -84,11 +86,26 @@ function SignUpPageContent() {
     void checkAuth()
   }, [checkAuth])
 
+  useEffect(() => {
+    if (cooldownSeconds <= 0) return
+
+    const timer = window.setInterval(() => {
+      setCooldownSeconds((current) => Math.max(0, current - 1))
+    }, 1000)
+
+    return () => window.clearInterval(timer)
+  }, [cooldownSeconds])
+
   const handleSignUp = async (event: React.FormEvent) => {
     event.preventDefault()
     setError("")
     setSuccess("")
 
+    if (!usePassword && cooldownSeconds > 0) {
+      setError(`Please wait ${cooldownSeconds}s before requesting another magic link.`)
+      return
+    }
+
     if (!email) {
       setError("Email is required")
       return
@@ -130,8 +147,12 @@ function SignUpPageContent() {
         const result = await signInWithOtp(email, true)
 
         if (result.success) {
+          setCooldownSeconds(MAGIC_LINK_COOLDOWN_SECONDS)
           setSuccess(result.message || "Check your email for the magic link to complete registration.")
         } else {
+          if (result.retryAfter) {
+            setCooldownSeconds(result.retryAfter)
+          }
           setError(result.error || "Sign up failed")
         }
       }
@@ -359,7 +380,7 @@ function SignUpPageContent() {
 
                 <Button
                   type="submit"
-                  disabled={isLoading || !!success}
+                  disabled={isLoading || !!success || (!usePassword && cooldownSeconds > 0)}
                   className="h-12 w-full rounded-lg text-sm font-semibold"
                 >
                   {isLoading ? (
@@ -367,6 +388,8 @@ function SignUpPageContent() {
                       <ArrowPathIcon className="h-5 w-5 animate-spin" />
                       {usePassword ? "Creating..." : "Sending..."}
                     </>
+                  ) : !usePassword && cooldownSeconds > 0 ? (
+                    <>Wait {cooldownSeconds}s</>
                   ) : (
                     <>
                       {usePassword ? "Create Account" : "Send Magic Link"}
diff --git a/lib/features/auth/auth-service.ts b/lib/features/auth/auth-service.ts
index 8b85476..36e6aa6 100644
--- a/lib/features/auth/auth-service.ts
+++ b/lib/features/auth/auth-service.ts
@@ -238,7 +238,7 @@ export async function signIn(
 export async function signInWithOtp(
   email: string,
   rememberMe = true,
-): Promise<{ success: boolean; error?: string; message?: string }> {
+): Promise<{ success: boolean; error?: string; message?: string; retryAfter?: number }> {
   const controller = new AbortController()
   const timeoutId = window.setTimeout(() => controller.abort(), 45000)
 
@@ -257,12 +257,14 @@ export async function signInWithOtp(
       success?: boolean
       error?: string
       message?: string
+      retryAfter?: number
     } | null
 
     if (!response.ok || !result?.success) {
       return {
         success: false,
         error: result?.error || 'Failed to send login link',
+        retryAfter: typeof result?.retryAfter === 'number' ? result.retryAfter : undefined,
       }
     }