---
title: Expires
summary: null
url: https://www.fastly.com/documentation/reference/http/http-headers/Expires
---

The `Expires` header is one of several headers that Fastly uses as a source of information when determining [how long to store something in cache for](https://www.fastly.com/documentation/guides/concepts/edge-state/cache/cache-freshness/).  In general `Cache-Control` should be preferred, because it offers a greater degree of control over the [behavior of the resource once it becomes stale](https://www.fastly.com/documentation/guides/concepts/edge-state/cache/stale/) in the cache.