---
title: "Let's Encrypt ACME authorization reuse period cut from 30 to 10 days: 2026-10-07 | Harbyn"
description: "Let's Encrypt ACME authorization reuse period cut from 30 to 10 days, announced Oct 7, 2026."
canonical: "https://harbyn.com/changes/letsencrypt/2026-10-07-64-day-certificate-lifetimes-coming-feb-2027-2"
last-updated: 2026-10-08
---

# Let's Encrypt ACME authorization reuse period cut from 30 to 10 days

Markdown version of <https://harbyn.com/changes/letsencrypt/2026-10-07-64-day-certificate-lifetimes-coming-feb-2027-2>.

Behavior change - Let's Encrypt. low severity. Announced.

Let's Encrypt will reduce the authorization reuse period from 30 days to 10 days, with no date given for this step, and to seven hours in 2028. Only ACME clients built to rely on validation reuse need changes.

## Facts

| Fact | Value |
| --- | --- |
| Vendor | [Let's Encrypt](https://harbyn.com/vendors/letsencrypt.md) |
| Kind | Behavior change |
| Severity | low |
| Status | Announced |
| Announced | Oct 7, 2026 |
| Added to Harbyn | Oct 8, 2026 |
| Lead time | No dated deadline |
| Vendor page | <https://letsencrypt.org/2026/10/07/64-day-certs.html> |
| Review | Reviewed by a person, extracted by a model |

## Find it in your code

```sh
npx harbyn scan
```

This change names no identifier the scanner can match line by line, so the scan tells you whether your repository uses Let's Encrypt, from its packages and API hosts. Nothing leaves your machine.

## Sources

Where this event comes from: the page we read, when we read it, and the hash of that snapshot.

- <https://letsencrypt.org/feed.xml> (changelog, fetched 2026-10-08 23:25 UTC, sha256 `a273e737e699f10a820e4ca99a63afcbb8cb7e5f95aa667ad75fc3a1cff31ac6`)

## Related changes

### More from Let's Encrypt

- [Default certificate lifetime changes to 64 days](https://harbyn.com/changes/letsencrypt/2026-10-07-64-day-certificate-lifetimes-coming-feb-2027.md) (Behavior change, effective Feb 10, 2027)

### Changes at other vendors

- [Amazon Selling Partner API: ORDER\_CHANGE notifications add PreFulfillmentStatusChange for Amazon Autos](https://harbyn.com/changes/amazon-sp-api/2026-10-14-sp-api-updates-new-listings-items-api-ivp-values-in-eu5-jp-and-ca-stores-oct-3.md) (effective Oct 28, 2026)
- [BigCommerce: 301 redirects will apply only to storefront channels](https://harbyn.com/changes/bigcommerce/2026-10-07-301-redirects-now-apply-to-storefront-channels-only.md) (effective Nov 10, 2026)
- [GitHub: Secret scanning audit log business field changes to enterprise slug](https://harbyn.com/changes/github/2026-10-20-updates-to-github-secret-scanning-7.md) (effective Nov 12, 2026)
- [Jira / Atlassian Cloud: New IP address ranges in use from January 1, 2027](https://harbyn.com/changes/atlassian-jira/2026-10-16-atlassian-cloud-adds-new-ip-address-ranges.md) (effective Jan 1, 2027)

[All upcoming deadlines](https://harbyn.com/deadlines.md)