HTTP 405 means the server recognizes the URL but does not allow the request method used for that resource. Uptime Basics labels an unaccepted 405 as Method not allowed.
Availability monitors support GET and HEAD. They do not send POST, PUT, PATCH, DELETE, a custom request body, or a browser form submission.
Check which method is configured
- Open the monitor.
- Open Monitor Tools and Advanced Request Options.
- Review Request method.
- Open Detailed Logs and confirm the 405 response.
- Check the web server or application logs for the same timestamp and method.
New monitors use GET by default because it is the most widely supported choice.
If the monitor uses HEAD
HEAD asks for response headers without downloading the response body. Some servers, frameworks, security services, and routes do not implement it correctly even though GET works.
For a paid monitor that receives 405 from HEAD, Uptime Basics can retry with GET when enough of the same timeout budget remains. If GET succeeds, the check is recorded as successful. If 405 remains in the log, GET may also be rejected or there may not have been enough time for a useful fallback.
Save GET as the monitor method when it consistently represents the customer experience. This avoids relying on a fallback and makes the result easier to interpret.
If the monitor already uses GET
Confirm that the endpoint is designed for a public GET request. An API route that only accepts POST or requires a request body is not a suitable direct availability target.
Create a lightweight GET health endpoint that:
- returns a normal success status when the service is ready;
- checks only the dependencies needed to serve customers;
- does not expose private data;
- does not perform a transaction or change state; and
- can be protected with a safe custom header or HTTP Basic Authentication when needed.
Check routing and security layers
A CDN, WAF, reverse proxy, or application gateway can reject a method before it reaches the application. Compare logs at each layer and review method allowlists, route rules, cached error responses, and recent security-policy changes.
Should you accept HTTP 405?
Only accept 405 when that exact response is intentionally used as a healthy signal for the selected endpoint. Accepting it proves that a rejecting HTTP layer answered; it does not prove that the customer-facing operation works.
If 405 is accepted, future 405 responses count as Up and no Method not allowed diagnosis is recorded. Prefer a normal GET health endpoint whenever possible.
When to contact Support
Contact Support if the saved GET or HEAD request succeeds from independent HTTP tools but Uptime Basics continues to receive 405.
Include the monitor name, URL, configured method, timestamps, redirect setting, and the names of relevant custom headers. Do not include header values, passwords, session cookies, or private keys.