Are smart locks worth it? Pros and cons

What counts as a smart lock?

Any lock you can open without a traditional key: with a code, your phone, or a home system. They differ mostly in how they connect.

• Keypad locks. Electronic, with a number pad and no app. Simple, and nothing to hack online, but codes are managed at the lock.
• Bluetooth locks. Talk to your phone when you are close. Good for unlocking as you walk up; to manage them from away you usually need a separate bridge.
• Wi-Fi locks. Connect straight to your home network, so you can check and change them from anywhere. They tend to use batteries faster.
• Hub-based locks. Use Z-Wave, Zigbee or Thread to talk to a home hub or alarm system. Batteries often last longer, but you need the hub.
• Matter. A shared standard so devices from different brands can work together. The group behind it says devices from multiple brands work natively together (Connectivity Standards Alliance).

Retrofit or full replacement: which kind should you get?

A retrofit fits over the inside half of your current deadbolt and keeps your outside key. A full replacement swaps the whole deadbolt and usually adds a keypad outside.

Retrofits are popular with renters and with anyone who likes their existing lock. The outside looks the same and your keys still work. They depend on the existing deadbolt turning smoothly, because the motor has to do the turning.

Full replacements give you a keypad, so nobody needs a phone to get in. They change the look of the door and usually come with their own key cylinder, which means new keys unless the cylinder is rekeyed to match your other locks.

What are the real advantages?

No keys to lose, easy access for other people, and a record of when the door was used. For many households those three outweigh the downsides.

• No lockouts from forgotten keys. A code or a phone is harder to leave on the counter.
• Codes for each person. A cleaner, a dog walker or a relative gets their own code, and you delete it when they no longer need it, without a rekey.
• Time-limited access. Many locks can make a code that only works on certain days or hours.
• A log. App-connected locks show when the door was locked and unlocked, and by which code.
• Auto-lock. The lock can throw the bolt after a set time, so a door left unlocked doesn't stay that way.
• Checking from away. With a Wi-Fi or hub connection you can see and change the lock's state from anywhere.

What are the downsides?

Batteries, accounts, updates and fit. A smart lock is a small computer on your door, and it needs the care a computer needs.

• Batteries. They run down, faster on Wi-Fi models and on doors that stick. You get warnings, but you have to act on them.
• Heat and sun. An outside keypad that sits in direct Memphis afternoon sun gets very hot. Check the maker's stated operating temperature range before you buy.
• A stiff door. If the bolt rubs on the strike, the motor strains, drains batteries and may jam. The door has to line up well first.
• Account security. Anyone who gets into your lock app can open your door. A weak or reused password is a real risk.
• Updates. The lock and app need updates to fix problems. A brand that stops supporting a model leaves you with a lock that no longer gets fixes.
• Smudges and shoulder surfing. Worn or greasy keypad buttons can hint at the code. Wipe it, and change codes now and then.

What happens when the batteries die?

The lock warns you first, often for days or weeks. If you ignore the warning, you need the lock's backup way in.

Backups vary by model, so learn yours before you need it:

• A key cylinder. Many smart locks keep a normal key slot. Keep a key somewhere other than inside the house.
• Outside battery contacts. Some keypads have contacts or a port underneath where a battery or power pack can wake the lock long enough to enter a code.
• No backup at all. Some keyless models rely only on the batteries. If yours does, change batteries on a schedule, not just on the warning.

Use fresh batteries of the type the maker names. Some locks report charge wrongly with rechargeable cells. If you get locked out anyway, a locksmith can usually get you in; our guide to being locked out of your house covers what to do first.

Will a smart lock fit your door?

Most standard US exterior doors take one, but measure before you buy. Door thickness, backset and a bolt that slides freely are the three things that decide it.

• Door thickness. Each lock lists the range it fits. Thick or thin doors may need a different model or an extra kit.
• Backset. The distance from the edge of the door to the center of the lock hole. Most locks adjust between the two common sizes; check yours matches.
• The bore hole. The big round hole through the door. Smart locks expect a standard size; an older door with an odd hole may need work.
• Bolt alignment. Close the door and turn the existing deadbolt by hand. If you have to push or lift the door, fix the alignment first.
• Room inside. The inside unit is bulky. Check it clears trim, a storm door handle, or a doorknob set close above or below.
• Grade. Smart locks are still locks. BHMA's consumer site, Secure Home, rates residential locks for security, durability and finish.

Unsure? Take a photo of the door edge and both sides of the lock. A locksmith can usually tell from photos whether it will fit as is.

How do you keep a smart lock secure?

Protect the account the way you would protect your bank login, keep the lock updated, and clean out old codes. Most smart lock risks come from the account, not the lock.

• Use a strong password that you use nowhere else. CISA recommends a password manager to create and store them (CISA on passwords).
• Turn on two-step sign-in in the lock's app if it offers it (CISA on MFA).
• Turn on automatic updates for the app and, where offered, the lock. CISA advises turning on automatic updates for devices and apps (CISA on updates).
• Delete codes for people who no longer need them. Give guests time-limited codes.
• Avoid codes like birthdays, house numbers or 1234.
• Keep one owner account for the home. Add others as users, not owners.

Does Matter matter?

Only if you use, or may use, more than one smart home system. Matter helps devices from different brands work together.

If your phone, speaker and lock all come from one ecosystem and you are happy with it, Matter adds little. If your household has mixed phones or you may switch systems later, a lock that supports Matter keeps more options open. Check the box or product page for the Matter logo, and check that your hub or controller supports locks.

Are smart locks a good idea for rentals?

They can be, with the landlord's written OK and a plan for turnover. Codes change in seconds between tenants, which is their biggest advantage there.

For tenants: ask before installing anything. A retrofit that keeps the original deadbolt and goes back the way it was is the easiest to get approved. Keep the original parts.

For landlords: a keypad means no keys to collect at move-out, but someone must own the admin account, change codes on every turnover and keep batteries fresh in empty units. Our key control guide for landlords covers how to track codes alongside keys.

Who is a smart lock a poor fit for?

People who won't keep up with batteries and updates, doors that don't latch well, and anyone who would rather not have a lock tied to an app.

A plain keypad deadbolt is a good middle ground. It gives you codes instead of keys, with no app or account to protect. A good mechanical deadbolt with a rekey when keys go missing is still a sound choice. If you decide to go ahead, see smart lock installation for what an installation involves.