Basics
My TLS certificate is expiring
What 13x checks
This is rule basics.certificate-expiry in the public registry: Certificate is not about to expire. It runs on every audit, against the pages we actually fetched, and its result is derived from the response rather than estimated.
- Surface
- Basics
- Score weight
- 14 of the readiness score
- Scope
- Runs on every audited page
- Applies
- Only where the market or the page shape makes it relevant
Registry version 2026-07-30. Every rule is published, and the audit is deterministic — the same page produces the same finding every time.
The fix
The same text the audit hands you when this check fails on your own site.
The certificate expires on ( days).
If you are on a managed host — Vercel, Netlify, Cloudflare, Railway, Fly — renewal is automatic, so reaching this point means something is blocking it. Usually DNS: the domain no longer points at the platform, or a CAA record forbids the issuing CA. Check the domain settings in the dashboard for a verification error.
On your own server with Certbot:
# Is the renewal timer actually running?
systemctl list-timers | grep certbot
# Dry-run the renewal to see the real error
sudo certbot renew --dry-run
# Renew now
sudo certbot renew --force-renewal && sudo systemctl reload nginxThe usual causes are a port 80 redirect that breaks the HTTP-01 challenge, or a webroot path that moved.
Then set up an alert. Let's Encrypt stopped sending expiry emails in 2025, so nothing will warn you next time.
Does your site have this problem?
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More basics checks
- My site is not served over HTTPSServed over HTTPS with a valid certificate
- How to redirect HTTP to HTTPSHTTP redirects to HTTPS
- My domain registration is about to expireDomain registration is not about to lapse
- My 404 page returns a 200 statusMissing pages return a real 404
- My certificate does not cover wwwCertificate covers apex and www
- Should I use www or non-wwwOne canonical host (www or non-www)