Quick answer
AWS Lambda's function timeout ceiling is 900 seconds (15 minutes). Each function can be configured lower, so the timeout that actually terminates an invocation is the function's current setting.
Verified Sep 17, 2026Official source
Current limits
| Constraint | Current value | Scope | Verified source |
|---|---|---|---|
| Function timeoutA function-level configuration ceiling; the configured timeout may be lower. Functions on AWS Lambda Managed Instances may set up to 5,400 seconds (90 minutes) for asynchronous and event-source-mapping invocations. | 900 seconds (15 minutes) | Platform documented | Amazon Web ServicesSep 17, 2026 |
Why does this limit matter?
Increasing a timeout can hide slow dependencies or retry storms instead of fixing them.
Synchronous callers, API gateways, and SDK clients can have shorter timeouts than Lambda itself.
What should you check?
- Read the function's configured Timeout value, not only the service quota.
- Compare p95/p99 execution duration and upstream client timeouts.
- Add bounded network timeouts and preserve time for cleanup and retries.
Important caveats
- The quota page's function limit is not the same as newer Lambda MicroVM execution limits.
- Downstream service timeouts can terminate the user journey first.
HyperObserve reports the documented platform constraint. Your application, SDK, gateway, provider, region, or account can impose a lower effective limit.
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