Introduction
The biggest pain of renting? Fumbling for keys with groceries in your hand, while knowing you can’t change the locks to a smart keypad.
Actually, you can. You just need a Retrofit Smart Lock. Unlike traditional smart locks that replace the entire deadbolt mechanism, retrofit locks only replace the thumb-turn (the latch you twist) on the inside. The outside keyhole remains untouched.
Why Landlords Are Okay With This
- The Key Still Works: Since the outside cylinder doesn’t change, your landlord’s master key still works perfectly.
- No Damage: It uses the existing screw holes. When you move out, you just screw the old plastic thumb-turn back on.
Top Retrofit Locks for 2026
1. August Wi-Fi Smart Lock (The Premium Choice)
The August lock is the most famous retrofit option. It looks like a sleek metal puck that sits over your deadbolt.
- Pros: Auto-Unlock (unlocks as you approach the door), works with everything (Apple HomeKit, Alexa, Google).
- Cons: Battery life can be short (3-6 months).
2. SwitchBot Lock Pro (The “No Tools” Choice)
Most locks require a screwdriver. The SwitchBot Lock Pro is unique because it can stick to your door using 3M VHB Industrial Tape.
- How it works: It has a “gripper” that grabs your existing latch and twists it.
- Pros: Requires literally zero tools. Strong motor.
- Cons: It’s a bit bulky looking compared to the August.
3. Wyze Lock (The Budget Choice)
A solid, affordable option that uses a retrofit design. It’s reliable but has fewer fancy features than August.
Installation Guide (Step-by-Step)
- Tape the Outside: Use painter’s tape to hold the outside part of your lock in place so it doesn’t fall out.
- Unscrew the Inside: Remove the two screws holding the inside thumb-turn plate.
- Choose the Adapter: The smart lock comes with colored adapters. Find the one that fits your metal “tailpiece.”
- Screw on the Base: Screw the smart lock mounting plate using the original screws.
- Snap on the Lock: Click the smart lock body onto the plate.
- Calibrate: Use the app to teach the lock what “Locked” and “Unlocked” feels like.