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))
+}
diff --git a/web/lib/firebase/storage.ts b/web/lib/firebase/storage.ts
index fcf4422d..3acfbae9 100644
--- a/web/lib/firebase/storage.ts
+++ b/web/lib/firebase/storage.ts
@@ -3,6 +3,8 @@ import imageCompression from 'browser-image-compression'
 import { nanoid } from 'nanoid'
 import { storage } from './init'
 
+const ONE_YEAR_SECS = 60 * 60 * 24 * 365
+
 export const uploadImage = async (
   username: string,
   file: File,
@@ -24,7 +26,9 @@ export const uploadImage = async (
     })
   }
 
-  const uploadTask = uploadBytesResumable(storageRef, file)
+  const uploadTask = uploadBytesResumable(storageRef, file, {
+    cacheControl: `public, max-age=${ONE_YEAR_SECS}`,
+  })
 
   let resolvePromise: (url: string) => void
   let rejectPromise: (reason?: any) => void