460 Client Closed Connection (ALB)

AWS ALB log code: the client closed the connection before the idle timeout elapsed.

460 at a glance

Code: 460
Name: Client Closed Connection (ALB)
Class: 4xx Client error
Status: Non-standard used by AWS Application Load Balancer
Documented by: AWS Application Load Balancer
Client receives: Nothing: the client already disconnected. 460 is written to ALB access logs only.
Cacheable by default: Not applicable: this code is never sent to the client.

What 460 means

AWS Application Load Balancers record 460 in their access logs when a client closed the connection before the load balancer could respond, before the idle timeout period ended. It is the ALB counterpart of nginx's 499 and is not sent to the client.

What typically causes a 460

Client-side timeouts shorter than the target's processing time (API clients, Lambda callers, browsers).
Users cancelling or navigating away from slow requests.

Fix it on the server

Compare target_processing_time in ALB logs with your clients' timeout; speed up the endpoint or move long work to async jobs.

Fix it as a client or visitor

Raise the client timeout for slow operations.

Example log line

h2 2026-11-10T12:00:00.000Z app/my-alb/50dc6c495c0c9188 203.0.113.7:51234 10.0.1.12:8080 0.001 -1 -1 460 - 210 0 "GET https://example.com:443/report HTTP/2.0" ...