Aqara Smart Lock U400 is an integrated smart lock that provides hands-free unlocking, multiple entry methods, and smart home connectivity. It supports Apple Home Key, fingerprint recognition, PIN codes, NFC cards, and mechanical keys. The included sensors automatically lock the door and support Aqara-specific Night Latch and Do Not Disturb modes for extra security. The U400 is not Wi-Fi enabled and instead relies on technologies like Matter over Thread, Bluetooth, UWB, and NFC. It also has a rechargeable lithium-ion battery, an IP65-rated exterior panel, and USB-C charging. The U400 works with compatible single-cylinder deadbolt doors, is compatible with Apple Home and other Matter-compatible platforms, and comes in various packages sold by select retailers.

What Access and Security Features Does the Aqara U400 Provide?

Here are the 3 Access and Security Features the Aqara U400 Provides:

1. Hands-Free UWB Home Key: The U400 unlocks with a touch of a finger using hands-free Home Key and UWB technology. UWB detects both distance and direction to identify an authorized user approaching the door from the outside. This is different from standard NFC Home Key access, where a compatible iPhone or Apple Watch is tapped close to the lock. Aqara also highlights its secure UWB communication to minimise relay and spoofing risks.
2. Fingerprint, Keypad, NFC & Physical Key: The fingerprint reader stores up to 50 fingerprints and enables quick biometric access. Aqara claims it recognizes in about 0.3 seconds, with recognition accuracy up to 98.6%. The keypad with touchscreen is permanently coded, offline coded, and time coded; Anti-Peep is protection against unwanted observation. It also supports Aqara NFC cards, the supported app and voice control, and a traditional mechanical key to unlock the lock. It is rekeyable, but a certified locksmith must verify the special design before replacement or rekeying.
3. Auto-Lock, Night Latch & Critical Alerts: Auto-Lock on Close uses the built-in gyroscope and door-status logic to lock the door after it closes. Night Latch Mode limits exterior keyless access, as Aqara documents. Do Not Disturb Mode prevents detection of normal noises but still tracks critical alerts such as forced entry and the door left open. These settings give you more control through Aqara's lock features.

What Are the Key Specifications of the Aqara U400?

Here are the 4 Key Specifications of the Aqara U400:

1. Matter over Thread, Bluetooth, UWB & NFC: The U400 supports Matter over Thread, Bluetooth, Ultra-Wideband (UWB), and NFC for smart-home connectivity. Matter over Thread lets the lock integrate with compatible ecosystems, while Bluetooth enables local communication and setup. UWB and NFC both support contactless access. UWB enables contactless access with compatible Apple devices. The Matter ecosystem utilizes the appropriate Matter Controller and Thread Border Router with the lock.
2. Rechargeable Battery & USB-C Power: U400 is powered by a rechargeable lithium-ion battery. Aqara claims up to 6 months of battery life on a single charge, but this varies with use. The battery is removable and supports USB charging via the inner lock or a compatible external charger. The battery that runs out still uses external power through a separate USB-C port, but it does not charge the internal battery. Low-battery warnings support charging, while hands-free UWB unlocking is unavailable at very low battery levels. Battery packs vary by package, with the selected Deluxe pack containing two batteries.
3. Dimensions, IP65 & Operating Limits: The interior panel measures approximately 178 × 76 × 46.9 mm, while the exterior panel measures approximately 167 × 76 × 25.5 mm. Aqara rates the exterior panel IP65 for dust and water resistance, but this does not mean the lock is suitable for submersion. It has a specified operating temperature range of approximately −18°C to 55°C, and Aqara also mentions a high non-condensing humidity tolerance. These specifications outline the product's operating conditions but cannot guarantee suitability for all outdoor door environments.
4. Versions & Included Hardware: The U400 comes in several retail and package versions. Standard models include one rechargeable battery, and some Deluxe models include two. Some bundles also include an Aqara Hub M100. The core package includes the lock, mechanical keys, mounting plate, deadbolt and strike hardware, screw kit, accessory kit, installation diagram, and user manual. Buyers should verify the exact listing, as finishes, battery quantities, hubs, and accessories vary by retailer and model.

Will the Aqara U400 Fit Your Existing Door and Deadbolt?

The Aqara U400 is compatible with analog single-cylinder deadbolt locks, but you must measure your current door lock to confirm compatibility before buying. Its manual specifies backset options of 60 mm or 70 mm (2-3/8 or 2-3/4 inches), door thickness of approximately 35–55 mm (1-3/8–2-1/8 inches), and a main bore of 38 mm or 54 mm (1-1/2 or 2-1/8 inches), depending on the door construction. Aqara recommends using a 54 mm bore instead of assuming a smaller hole will work when installing a sensor on solid doors. Install the provided strike plate according to the manufacturer's instructions. Change it before installing the lock if the hole or door is nonstandard. After installation, calibration is necessary for proper locking and door-status detection. Keep the lock within about 5 meters of the Matter Controller, or about 3 meters away if walls or other obstructions are between them.

How do I use the Aqara U400 with Apple Home, Apple Home Key, and Apple Matter?

The Aqara U400 is compatible with Apple Home and Apple Home Key, which means only compatible residents can add a digital home key to Apple Wallet through the supported Apple Home setup. It requires a compatible Apple Home hub with updated software to control Apple Home. The lock pairs with compatible smart-home networks, such as Apple Home and other officially listed home networks. Each ecosystem requires a suitable Matter Controller and Border Router. Apple Home Key and UWB hands-free unlocking are not supported generically and rely on Apple-supported hardware and software. Aqara Home also provides product-specific controls, such as auto-lock configuration, credential management, and Night Latch settings. Third-party Matter platforms offer a different set of lock features, which you should review before choosing a preferred ecosystem.

How Much Does the Aqara U400 Cost, and Which Versions Are Available?

Aqara's U.S. store lists the standard Aqara Smart Lock at $269.99, and Apple's U.S. store lists the U400 Deluxe Kit at $299.95. These prices reflect different package combinations and should not be interpreted as the Deluxe Kit being the same product bundle as the standard price. Aqara has announced availability in the US, Canada, Australia, New Zealand, and Singapore, with various versions and packages available through specific channels. These include regular models with an Aqara Hub M100 add-on and Deluxe models with extra rechargeable batteries. Finish and package availability is dependent on the retailer and region. Verify local prices, accessories, warranty, and availability before ordering. Prices and availability were verified on October 25, 2026; please verify before use, as retailer listings and product bundles change.