API Degraded Performance

Update timeline

1. investigating Jun 18, 2026, 04:04 PM UTC

   Let's Encrypt's production API is experiencing degraded performance. Clients may encounter 400 and 500 error responses. We are actively investigating the issue.

2. investigating Jun 18, 2026, 04:35 PM UTC

   We have taken measures to stabilize API performance while we investigate networking issues between our two high assurance data centers.

3. investigating Jun 18, 2026, 07:40 PM UTC

   We are continuing to investigate degraded performance and elevated error rates.

4. investigating Jun 18, 2026, 11:59 PM UTC

   We are still investigating the issue with our upstream ISP.

5. investigating Jun 19, 2026, 04:45 AM UTC

   We're operating normally, but with reduced redundancy. We continue to work with our upstream ISP to identify and resolve the issue.

6. identified Jul 02, 2026, 06:05 PM UTC

   Starting shortly, we will be performing maintenance on networking equipment in High Assurance Datacenter 1. Some clients may experience errors while traffic shifting occurs.

7. investigating Jul 02, 2026, 10:18 PM UTC

   We're receiving reports of increased timeouts to our API following a swap of our active datacenters. We are investigating and reverting that change.

8. monitoring Jul 02, 2026, 10:52 PM UTC

   API traffic has been swapped back between datacenters.

9. monitoring Jul 02, 2026, 11:15 PM UTC

   After monitoring we have confirmed our API is operational.

10. investigating Jul 03, 2026, 01:20 AM UTC

    We're noticing elevated 503s and slow responses. Investigating.

11. monitoring Jul 03, 2026, 01:32 AM UTC

    Elevated 503s and slow responses resolved, back to operational.

12. resolved Jul 23, 2026, 01:39 AM UTC

    All services remain operational, and we've now restored full internal redundancy.