Door Lock Buying Guide

The door lock market doesn’t change as quickly as the markets for other products, such as appliances and electronics, but there is plenty of change afoot when it comes to smart locks.

Internet-connected smart locks are improving in a number of ways. Newer models connect directly to WiFi, negating the need for hubs and bridges that connect them to the internet. Some smart locks now feature fingerprint sensors, giving you a way to unlock your door without a key, a PIN code, or a smartphone. And retrofit smart locks (models that essentially add smarts to your existing lock) are getting smaller.

August (a sister brand of Yale) made its latest retrofit model, the August WiFi Smart Lock, smaller than the previous version. But a new startup called Level has made its retrofit model, the Level Bolt, so small that it simply replaces the bolt of your existing deadbolt.

Smart locks will see more changes as the smart home industry adopts a new communications standard called Matter. Through this standard, smart home devices from different manufacturers will be able to talk to each other without the need for dedicated partnerships between companies.

The standard already has support from Amazon, Apple, Google, Samsung, and over 170 other companies, including Assa Abloy (parent company of August and Yale), Kwikset, Level, and Schlage. Matter-certified products are expected to enter the market by the end of 2021.

The deadbolts, electronic locks, and smart locks that enter CR’s labs get kicked, picked, and drilled into oblivion.

For the kick-in tests, CR’s test engineers built a custom jig that allows them to swing a 100-pound steel battering ram at a replaceable section of door with the deadbolt installed. They repeat the test eight times, at increasing heights, or until the lock fails. The models that fail—and at least half do—then go through another test round with a reinforced box strike plate installed on a new lock sample. Again and again, CR’s experts have found that this basic do-it-yourself upgrade improves security for any lock (more on that later).

For the drilling test, we evaluate how well each lock can withstand attack from a cordless drill. And for the picking test, we assess the internal mechanisms of each lock to see how easily they can be picked.

All models, including smart locks, receive a score in each of the four break-in tests, allowing you to easily compare each lock’s strengths and weaknesses in the face of a physical breach. The only exception is retrofit smart locks. These locks replace only the interior side of your existing deadbolt, essentially adding smarts to the lock you already use. As a result, a retrofit smart lock’s resistance to kicking, picking, and drilling is entirely dependent on the deadbolt it’s paired with.

Both types of smart locks also get additional testing. We investigate features such as smartphone alerts, remote locking and unlocking, geofencing (the ability to automatically lock or unlock the door based on your phone’s location), voice control (via Amazon Alexa, Google Assistant, and Apple’s Siri), shareable electronic keys, access logs of who comes and goes, and even tamper alarms. Our testers factor these features into our ratings for ease of remote access, convenience, and security add-ons. We also run through the wireless setup process to see how difficult it is to connect the locks to a smartphone and other smart home devices (such as smart speakers), putting ourselves in your shoes. For the details on how well each door lock performs in these tests, see the results in our door lock ratings. 

Very few locks we rate earn a high Overall Score, and some locks prove to be far more susceptible than most to brute-force attacks. Below are a few key takeaways.

Drills Easily Open Most Locks
With all but the high-security locks we test, even an ordinary cordless drill can disable the cylinders in 2 minutes or less. Our drill test on the Medeco Maxum 11*603, which has hardened cylinders, ruined the lock but denied access. So you’d have to replace the lock but not the contents of your home.

Parts Are Often Inadequate
All locks come with a strike plate that attaches to the doorjamb. But as we’ve reported in the past, many of these come with short screws that catch only the jamb and not the framing of the house. The kick-in resistance of most locks improves dramatically when we replace a stock strike plate with 3-inch screws and a box strike, which you can buy online for as little as $5. “We think manufacturers should include beefier hardware with their locks,” says CR’s lock test engineer, David Trezza. “A lock should be secure without consumers having to buy an aftermarket part.”

New Technologies Don’t Solve Old Problems
We find keypad-operated door locks to be convenient. These models allow you to create codes for temporary access to guests and contractors; you can delete the codes when access is no longer needed, without having to change the lock or call a locksmith. This process is even easier with smart locks, most of which allow you to create and delete PIN codes and electronic keys from your smartphone. But many of these high-tech locks are still susceptible to physical break-in tactics, such as drilling and picking.

1. Learn Lock Lingo
The deadbolts we’ve tested, both conventional and smart, are usually single-cylinder, operated using a key (or keypad and PIN code) from outside or a thumb-turn from inside. The high-security locks have hardened cylinders, unique pin configurations, and other defenses. Industry rankings, Grades 1 to 3, seem to track with our ratings, with Grade 1 locks being the most difficult to disable. But packages don’t always display that information, so you might have to check company websites to find out how a lock is rated.

2. Decide How Much You Can Spend
A high-security lock of the Medeco caliber might seem expensive, and smart locks aren’t cheap, either. But if you have a break-in, the deductible on your homeowners insurance is likely to be higher than the cost of the lock. And insurance policies commonly give discounts for homes with deadbolts.

3. Determine Whether You Want a Smart Lock
The price alone might be enough to make you scoff at buying a smart lock, but before you dismiss it, consider the convenience it delivers. A smart lock can be very helpful if you often forget to lock your door, or need to let contractors or cleaners in when you’re not home.

Smart locks solve those problems by way of smartphone apps and optional remote locking and unlocking features. Just know that remote access usually requires the use of some sort of WiFi bridge, at an additional cost. (Most smart locks don’t have WiFi built in because the chips are too power-hungry for the AA batteries that typically power them, but that is changing.) And if you’re considering a smart lock but don’t want to pay extra for WiFi access, an electronic lock might serve your needs. This type offers keypad access and the ability to program and distribute PIN codes to various guests, but it can’t talk to your smartphone.

4. Beef Up the Door Frame and Lock
Weak doors—in particular, hollow-core doors—may give way before the lock does. Whichever type of lock you buy, be sure to use a box strike made of heavy-duty metal and install it with the screws provided. Another option is to install 3-inch screws on your existing strike plate. Hinges should also be secured with 3-inch screws.

You might not want to spring for a double-sided lock, though; many municipalities consider them to be a fire hazard because you need a key to unlock the door from inside, which creates the possibility of being trapped. But they can offer peace of mind if installed on a door adjacent to glass sidelites by robbing a would-be burglar of the ability to break the glass and reach in to unlock the thumb-turn.