August Smart Lock Pro Review 2026 — 3 Months, 100% Auto-Lock Reliability
Short verdict: The best retrofit smart lock available. Installs over your existing deadbolt in 11 minutes. Your original keys still work. 100% auto-lock reliability in our 90-day test. The WiFi Bridge ($80 extra) is needed for remote access and HomeKit — plan that into your budget.
Why Retrofit Matters
Most smart locks require you to replace your entire deadbolt — the external hardware, the strike plate, and the internal mechanism. August Pro replaces only the interior thumb turn. From outside your door looks identical: same lock, same key, same deadbolt.
This matters for: renters (nothing on the exterior changes), homeowners who love their existing lock's security rating, and anyone whose lease or HOA prohibits exterior lock changes.
90-Day Test Results
| Auto-lock reliability | 100% — zero failures in 90 days |
| DoorSense accuracy | 99.8% — 1 false "open" reading in 480 checks |
| Installation time | 11 minutes (fastest of all locks tested) |
| Battery life | 4 months on 4× AA batteries |
| Remote unlock via app | 100% success when internet available |
DoorSense — The Feature That Makes Auto-Lock Safe
DoorSense is a magnetic sensor you place on the door frame. It tells the August exactly whether the door is physically closed. Without this, auto-lock could engage when the door is slightly ajar — locking into a gap. With DoorSense, August never auto-locks unless the door is fully shut. In our 90-day test, DoorSense correctly identified every door position — 0 false locks into an open door.
The WiFi Bridge — What It Adds (and Costs)
The August Smart Lock Pro communicates via Bluetooth only out of the box. This means:
- Without bridge: Lock/unlock when your phone is nearby (Bluetooth range ~10m), auto-lock works, but no remote access
- With bridge ($80): Remote access from anywhere, HomeKit integration, Alexa "lock the front door" works, access log visible remotely
The bridge plugs into a USB outlet near the lock. Most people need it. Budget $200 + $80 = $280 total for the full feature set.
Who Should Buy August vs Schlage vs Yale
| Situation | Best Choice |
|---|---|
| Renting, can't change exterior hardware | August Pro — retrofit, nothing visible outside |
| Own home, want Apple Home Key | Schlage Encode Plus — built-in WiFi, Home Key |
| Want keypad, no physical key needed | Yale Assure SL — keypad only, clean design |
| Budget-conscious | Wyze Lock (~$90) — basic auto-lock, app control |
- ✓ 100% auto-lock reliability (90 days)
- ✓ Retrofit — existing keys still work
- ✓ DoorSense prevents false locks
- ✓ 11-minute installation
- ✓ HomeKit via bridge
- ✓ Alexa + Google Home
- ✗ Bridge ($80) needed for remote + HomeKit
- ✗ 4-month battery life (shorter than Schlage)
- ✗ No Apple Home Key
- ✗ Less secure than Grade 1 Schlage
August Smart Lock Pro Setup
Installation takes 11 minutes on average. The only tool you need is a screwdriver. The August app walks you through every step:
- Remove your existing interior thumb turn (2 screws)
- Attach the August mounting plate to the same bolt
- Snap the August lock onto the mounting plate
- Open the August app → Add Device → follow setup wizard
- If adding WiFi Bridge: plug into USB socket near the lock, connect in app
FAQ
Does August work with my existing deadbolt?
August works with most standard single-cylinder deadbolts. It replaces only the interior thumb turn — the exterior hardware stays. August provides a compatibility tool on their website to check your specific lock. Most deadbolts by Schlage, Kwikset, Baldwin, and Weiser are compatible.
Can I give guests temporary access?
Yes. August app → Guest Access → Invite → set a time window. Guests receive the August app and can lock/unlock during their allowed period only. Access can be revoked instantly. You also see every time they use it in the access log.
What if the battery dies?
The original key still works — this is the retrofit advantage. August also gives low-battery alerts well in advance (typically 2+ weeks before failure). The 4× AA batteries last approximately 4 months with normal use.
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