August Smart Lock Review: The Best Retrofit Lock in 2025?

The August Smart Lock has been one of the most popular smart locks on the market for years, and for good reason. Unlike most smart locks that replace your entire deadbolt, the August installs on the interior side of your existing deadbolt — letting you keep your current keys while adding smartphone control. If you’re a renter, live in an HOA community, or just don’t want to replace your exterior hardware, the August is worth a serious look.

What Is the August Smart Lock?

August currently sells several models, including the August Smart Lock (Wi-Fi), the August Smart Lock Pro, and the August Wi-Fi Smart Lock. All share the same core concept: a motorized thumb-turn replacement that connects to your phone. The latest Wi-Fi models include a built-in Wi-Fi module so you don’t need a separate bridge or hub — a big improvement over older versions.

Key features across the lineup include:

• Auto-Lock and Auto-Unlock based on your phone’s location
• Activity log for all lock and unlock events
• Virtual keys to share access with family, guests, or service workers
• Alexa, Google Assistant, and Apple HomeKit compatibility
• DoorSense technology that detects whether your door is closed or open

Installation

Tools and Compatibility

August locks work with most standard single-cylinder deadbolts. Before purchasing, check that your deadbolt’s tailpiece (the metal post that the thumb-turn rotates) fits August’s included adapters. August includes multiple adapters in the box and has a compatibility checker on their website.

The Process

Installation is genuinely simple — no electrician or locksmith required. You remove the interior portion of your existing deadbolt, attach the August mounting plate, and snap the lock body onto it. The whole process takes about 10–15 minutes and requires only a screwdriver.

This retrofit approach is a big deal in Florida, where many homes are rentals or part of HOAs with restrictions on exterior door hardware changes. You keep your existing keys, your exterior lock looks exactly the same, and you gain all the smart features on the inside.

Features and Daily Use

Auto-Unlock

Auto-Unlock is the killer feature. When your phone detects you approaching your home, the door unlocks automatically. It uses a combination of geofencing and Bluetooth proximity, so it triggers reliably as you walk up — not when you’re still driving down the street. After a week of use, it feels natural and hard to live without.

Auto-Lock

Set the lock to automatically engage after 30 seconds, 1 minute, 5 minutes, or any custom interval after the door closes. Combined with DoorSense (which confirms the door is actually shut), this means you’ll never worry about leaving the door unlocked again.

Virtual Keys and Guest Access

This is one of August’s strongest features for households with multiple people coming and going. You can send a virtual key to a family member, dog walker, house cleaner, or contractor that:

• Works for a specific date and time range
• Sends you a notification when used
• Can be revoked instantly from the app

For Florida vacation rental owners or anyone using their property as a short-term rental, this kind of access management is invaluable.

Activity Log

Every lock and unlock event is logged with a timestamp and who triggered it — whether that was a person, Auto-Unlock, a virtual key, or the physical key from outside. The log gives you a clear picture of who came and went, and when.

Smart Home Integration

The August Smart Lock works across major platforms:

• Amazon Alexa: “Alexa, lock the front door” works seamlessly. Alexa won’t unlock by voice by default (a security measure), but you can enable it with a PIN.
• Google Assistant: Similar voice control capabilities.
• Apple HomeKit: Full support allows you to use the Home app, Siri, and HomeKit automations. This is a big win for iPhone households.

The HomeKit integration in particular is well-implemented, and if you have other HomeKit devices, the August fits right into existing automations.

Battery Life and Reliability

The August Smart Lock runs on 4 AA batteries. August claims up to 3 months of battery life under normal use, though heavy-traffic doors will drain them faster. The app sends low-battery warnings before you’re stuck. In humid Florida climates, we saw slightly faster battery drain than average — worth keeping a spare set of AAs nearby.

Connectivity is reliable over Wi-Fi. Occasional reconnection hiccups have been reported by some users, but these are typically resolved with a firmware update or router placement adjustment.

Potential Drawbacks

• No exterior keypad on the base model — guests need the app or a physical key unless you add an August Access Keypad separately
• Motorized sound — it’s not silent; you’ll hear it lock and unlock
• Battery-powered only — no hardwired option
• Price — at $149–$199, it’s mid-range; cheaper alternatives exist

Who Should Buy the August Smart Lock?

The August is ideal for:

• Renters who can’t change their exterior hardware
• Homeowners in HOAs with restrictions on front door appearance
• People who want to keep their existing keys
• Apple HomeKit users who want seamless integration
• Anyone managing short-term rental access or frequent guests

Final Verdict

The August Smart Lock is one of the most convenient and well-designed smart locks available. The retrofit installation, reliable Auto-Unlock, and broad smart home platform support make it a top pick for 2025. If you want smart lock features without replacing your entire deadbolt assembly, August remains the gold standard.

Rating: 4.5/5 — Excellent retrofit smart lock with great platform support.