---
title: "Vercel CDN no longer caches responses with Vary: Cookie: 2026-09-30 | Harbyn"
description: "Vercel CDN no longer caches responses with Vary: Cookie, announced Sep 30, 2026."
canonical: "https://harbyn.com/changes/vercel/2026-09-30-vercel-cdn-no-longer-caches-responses-with-vary-cookie"
last-updated: 2026-10-02
---

# Vercel CDN no longer caches responses with Vary: Cookie

Markdown version of <https://harbyn.com/changes/vercel/2026-09-30-vercel-cdn-no-longer-caches-responses-with-vary-cookie>.

Behavior change - Vercel. medium severity. In effect.

Vercel CDN no longer caches origin responses whose Vary header includes Cookie; they show x-vercel-cache MISS and the Runtime Logs reason vary\_key\_denied:cookie. Remove Cookie from Vary if responses do not depend on cookies, or keep it and send Cache-Control: private for personalized responses.

## Facts

| Fact | Value |
| --- | --- |
| Vendor | [Vercel](https://harbyn.com/vendors/vercel.md) |
| Kind | Behavior change |
| Severity | medium |
| Status | In effect |
| Announced | Sep 30, 2026 |
| Added to Harbyn | Oct 2, 2026 |
| Lead time | No dated deadline |
| Vendor page | <https://vercel.com/changelog/vary-cookie-responses-no-longer-cached> |
| Review | Reviewed by a person, extracted by a deterministic parser |

## 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 Vercel, 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://vercel.com/atom> (changelog, fetched 2026-10-02 01:24 UTC, sha256 `6c060f720f5d2afac726046272985f35e4a3abd7394fb04b51384881824995f8`)

## Related changes

### More from Vercel

- [Edge Requests are now called CDN Requests](https://harbyn.com/changes/vercel/2026-09-30-edge-requests-are-now-called-cdn-requests.md) (Behavior change, announced Sep 30, 2026)
- [Sandbox.create() now resolves only when the sandbox is ready](https://harbyn.com/changes/vercel/2026-10-08-vercel-sandbox-creation-now-returns-a-ready-sandbox.md) (Behavior change, announced Oct 8, 2026)
- [Node.js 20 disabled for new Builds and Functions deployments](https://harbyn.com/changes/vercel/2026-07-14-node-js-20-is-being-deprecated.md) (Retirement, effective Oct 1, 2026)

### 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)