How to Handle API Rate Limits

Treat 429 as a control signal

A 429 response should trigger controlled retry behavior rather than immediate tight loops. Log the request context, inspect any reset timing, and avoid retry storms that make the problem worse.

Separate retryable and non-retryable failures

Rate-limit responses should move through a different code path than invalid authentication, malformed requests, or exhausted plan quotas. This keeps your alerting cleaner and reduces wasted retries.

Use exponential backoff and queues

Applications that make recurring API calls should prefer queued retries or worker scheduling over direct synchronous retry loops.

var delay = TimeSpan.FromSeconds(Math.Min(60, Math.Pow(2, attempt)));
await Task.Delay(delay, cancellationToken);

Make quota visible to operators

Teams usually get into trouble when quota and concurrency are invisible. Track request volume, burst patterns, and failure rates in dashboards so you can adjust plan size or worker behavior before users notice.

Design user-facing fallbacks

If the API powers a product surface, decide what happens when traffic is throttled. You might show cached data, queue the job for later completion, or surface a clear delayed-processing state instead of a generic error.