diff --git a/src/database/mongo.js b/src/database/mongo.js
index 4e2ba46a66..4179111812 100644
--- a/src/database/mongo.js
+++ b/src/database/mongo.js
@@ -87,9 +87,13 @@ mongoModule.createIndices = async function () {
 	await collection.createIndex({ _key: 1, score: -1 }, { background: true });
 	await collection.createIndex({ _key: 1, value: -1 }, { background: true, unique: true, sparse: true });
 	await collection.createIndex(
-		{ members: 1, _key: 1}, { background: true, partialFilterExpression: { members: { $exists: true } } }
+		{ members: 1, _key: 1},
+		{ background: true, partialFilterExpression: { members: { $exists: true } } }
+	);
+	await collection.createIndex(
+		{ expireAt: 1 },
+		{ expireAfterSeconds: 0, background: true, partialFilterExpression: { expireAt: { $exists: true } } },
 	);
-	await collection.createIndex({ expireAt: 1 }, { expireAfterSeconds: 0, background: true });
 	winston.info('[database] Checking database indices done!');
 };
 
diff --git a/src/upgrades/4.11.0/expireAt-partial-index.js b/src/upgrades/4.11.0/expireAt-partial-index.js
new file mode 100644
index 0000000000..6c47911c06
--- /dev/null
+++ b/src/upgrades/4.11.0/expireAt-partial-index.js
@@ -0,0 +1,26 @@
+'use strict';
+
+
+const db = module.parent.require('./database');
+
+module.exports = {
+	name: 'Change expireAt index to partial index',
+	timestamp: Date.UTC(2026, 3, 3),
+	method: async function () {
+		const nconf = require.main.require('nconf');
+		const isMongo = nconf.get('database') === 'mongo';
+		if (!isMongo) {
+			return;
+		}
+		await db.client.collection('objects').dropIndex('expireAt_1');
+		await db.client.collection('objects').createIndex(
+			{ expireAt: 1 },
+			{
+				expireAfterSeconds: 0,
+				background: true,
+				partialFilterExpression: { expireAt: { $exists: true } },
+			},
+		);
+	},
+};
+