diff --git a/functions/src/scripts/set-avatar-cache-headers.ts b/functions/src/scripts/set-avatar-cache-headers.ts
new file mode 100644
index 00000000..676ec62d
--- /dev/null
+++ b/functions/src/scripts/set-avatar-cache-headers.ts
@@ -0,0 +1,27 @@
+import { initAdmin } from './script-init'
+import { log } from '../utils'
+
+const app = initAdmin()
+const ONE_YEAR_SECS = 60 * 60 * 24 * 365
+const AVATAR_EXTENSION_RE = /\.(gif|tiff|jpe?g|png|webp)$/i
+
+const processAvatars = async () => {
+  const storage = app.storage()
+  const bucket = storage.bucket(`${app.options.projectId}.appspot.com`)
+  const [files] = await bucket.getFiles({ prefix: 'user-images' })
+  log(`${files.length} avatar images to process.`)
+  for (const file of files) {
+    if (AVATAR_EXTENSION_RE.test(file.name)) {
+      log(`Updating metadata for ${file.name}.`)
+      await file.setMetadata({
+        cacheControl: `public, max-age=${ONE_YEAR_SECS}`,
+      })
+    } else {
+      log(`Skipping ${file.name} because it probably isn't an avatar.`)
+    }
+  }
+}
+
+if (require.main === module) {
+  processAvatars().catch((e) => console.error(e))
+}