August vs Level: Which Retrofit Smart Lock?

Retrofit locks are their own category, and a slightly under-appreciated one. Instead of ripping out your deadbolt and starting again, they keep the lock you have and make it smart from the inside. Your keys keep working. The landlord’s key keeps working. Nothing about the exterior changes. For renters that is the difference between a lock they can fit and one they cannot, and for owners it means the door furniture they chose stays the door furniture they have.

August and Level are the two serious options, and they take the idea to different extremes.

The short version

Buy Augustif you want retrofit smarts at a sensible price and you use Alexa, Google or Apple — it works with all three, has Wi-Fi built in, and does the job well. Buy Level if the appearance of your door genuinely matters to you and you live in Apple Home, because it hides every trace of the technology inside the deadbolt and adds Home Key tap-to-unlock.

Side by side

August: the practical retrofit

August’s design has been refined over several generations and the 4th gen fixed its biggest annoyance by building Wi-Fi in— no separate bridge plugged into a hallway socket. It mounts on the interior side of your existing single-cylinder deadbolt, and the exterior is entirely unchanged, which is what makes it the standard recommendation for renters and for anyone unwilling to give up their keys.

Its most useful features are the mundane ones: auto-unlock as you approach with your phone, DoorSense telling you whether the door is actually shut rather than merely locked, and remote access for letting someone in. It also works with all three major ecosystems— Alexa, Google Home and Apple Home — which is unusual and genuinely valuable in a mixed household.

The costs: the interior escutcheon is bulky, and you will see it every time you leave the house. Battery life is only okay with Wi-Fi always on, because keeping a radio awake costs power. And there is no keypad in the box— entry is by phone or by your existing key unless you add the accessory keypad, which is worth budgeting for if you want someone to get in without a smartphone. Our August review has the detail.

Level: the lock you cannot see

Level took the retrofit idea and asked what would happen if the technology disappeared entirely. The answer is the Lock+, where the motor and electronics live inside the deadbolt itself and the visible hardware is a normal-looking lock. From either side of the door, nothing announces that anything has changed. For a period property, a carefully chosen front door, or simply someone who dislikes gadgets on display, that is a real and defensible reason to spend more.

It is also Apple-Home-native in a way little else is, with Home Keysupport so an iPhone or Apple Watch unlocks the door with a tap — no app, no code, no key. In an Apple household that is the smoothest entry experience available, and it sits alongside the Schlage Encode Plus on our Apple Home lock picks.

The costs are equally clear. It is expensive, and a meaningful part of what you are buying is the industrial design. Its best features assume Apple Home; on Android you lose the Home Key advantage and much of the reason to choose it, which is why we point Android households at August or Yale instead. And it takes a CR2 batteryrather than AAs — not a problem, but not the cell in your kitchen drawer either. The full write-up is in our Level Lock+ review.

The connectivity difference nobody mentions

This is the practical distinction that catches people out. August has Wi-Fi built into the lock, so it reaches the internet on its own and remote access works out of the box. Level is a Bluetooth lockthat gets its remote access through Apple Home — which means you need an Apple Home hub in the house, a HomePod or an Apple TV, for anything to work when you are not standing next to the door.

If you already have a HomePod minithat is a non-issue and the Bluetooth design is arguably better, since it draws far less power. If you do not, the Level’s real cost is the lock plus a hub, and that changes the arithmetic considerably. Worth checking before you order; our hub guide explains what a home hub does and when you need one.

Which should you buy?

Augustfor most people, and for nearly all renters. It is the cheaper lock, it works with every major ecosystem, it has its own Wi-Fi, and it delivers the whole point of a retrofit — smart access without touching the exterior of the door or your keys. Add the accessory keypad if anyone in the household needs code entry.

Levelif you are in an Apple household, you already have a home hub, and you want the door to look exactly as it does now. Home Key tap-to-unlock is genuinely the nicest way to open a door, and invisible hardware is a real benefit rather than a vanity if you care about your entrance. Neither lock charges a monthly fee, both keep working from the outside with your existing key, and both deserve a strong unique password and two-factor authentication on the account behind them — standard CISA and NIST guidance, and more important on a lock than on anything else in the house. For the wider field, including keypads and full deadbolt replacements, see our best smart locks roundup.