What it means
Deprecated. It once told the client to repeat the request through the proxy in Location. Browsers ignore it for security reasons.
Common causes
- Very old servers or misconfiguration
How to fix it
As a client or visitor
Ignore it; modern clients will not follow it. Configure proxies in client settings instead.
As the site or API owner
Do not send 305. Configure proxies through PAC files or network settings.
Example response
HTTP/1.1
HTTP/1.1 305 Use Proxy
Date: Tue, 07 Oct 2025 09:30:00 GMT
Server: nginx
Location: http://proxy.example.com:8080/
Content-Length: 0Specification
FAQ
› Why was 305 deprecated?
Letting a server choose a client's proxy is a security risk, so browsers never implemented it.
› What happened to 306?
306 (Switch Proxy) is reserved and unused; it was dropped before it was standardized.