Smart Lock Buying Guide

Before you buy anything

Smart locks are one of those product categories where it’s easy to get overwhelmed. There are dozens of options, each with different features, connectivity standards, and price points. And the marketing doesn’t help. Every lock claims to be the most secure, most convenient, most innovative option on the market.

This guide cuts through that. I’ll walk through what actually matters when choosing a smart lock, based on years of installing and testing them.

Connectivity: picking the right protocol

This is the single most important decision you’ll make, and it affects everything else about your experience.

Bluetooth

The simplest option. Bluetooth locks communicate directly with your phone when you’re in range (usually 20-30 feet). They’re generally the most reliable, have the best battery life, and don’t require any additional hardware.

The downside: no remote access. You can only lock/unlock when you’re physically near the door. For a lot of people, that’s fine. You’re at the door when you need to use it, after all.

WiFi

WiFi locks connect to your home network and give you remote access from anywhere. You can lock or unlock from across town, check the status while you’re at work, and get real-time notifications.

The tradeoff is battery life. WiFi radios are power-hungry. Expect 3-8 months depending on the lock and how often it communicates. Some WiFi locks are better than others at managing power, but it’s always going to be less than Bluetooth-only.

Z-Wave / Zigbee

These are mesh networking protocols popular in the smart home world. They use very little power (similar to Bluetooth) but require a hub (like SmartThings or Hubitat). If you already have a Z-Wave or Zigbee hub, these locks integrate smoothly into your existing system and give you remote access through the hub.

If you don’t have a hub, these don’t make much sense as a starting point.

Thread / Matter

Thread is the newer mesh protocol that Apple, Google, and Amazon are all supporting. It’s low-power like Z-Wave but doesn’t require a dedicated hub. Most modern HomePod Minis and Apple TVs act as Thread border routers automatically.

Matter is the application layer that sits on top of Thread (and other protocols) to provide cross-platform compatibility. A Matter-compatible lock should work with Apple Home, Google Home, and Alexa without needing separate integrations.

Thread/Matter support is becoming more common but isn’t universal. If cross-platform compatibility matters to you, look for Matter certification.

Security ratings explained

ANSI/BHMA Grades

• Grade 1: Commercial grade. Tested to 800,000 cycles. Withstands significant force. This is overkill for most homes, but it’s the most durable option.
• Grade 2: Residential heavy-duty. Tested to 400,000 cycles. This is what I recommend for front doors.
• Grade 3: Basic residential. Tested to 200,000 cycles. Fine for interior doors or secondary entrances.

What the grade doesn’t tell you

The ANSI/BHMA grade tests the physical mechanism. It doesn’t evaluate the smart features. A Grade 1 lock with terrible Bluetooth encryption is still vulnerable digitally. Look for AES-128 or AES-256 encryption in the wireless communications, and make sure the manufacturer has a track record of issuing firmware updates.

Door compatibility

Before you order anything, check these measurements on your door:

• Door thickness: Most smart locks fit doors 1-3/8” to 1-3/4” thick. Thinner or thicker doors may need adapters or won’t work at all.
• Bore hole diameter: Standard is 2-1/8”. If yours is different, you may need to enlarge it.
• Backset: This is the distance from the edge of the door to the center of the bore hole. Standard is either 2-3/8” or 2-3/4”. Most smart locks include an adjustable latch that works with both.
• Door handedness: Some locks are handed (left or right). Most modern smart locks are reversible.

If you’re replacing an existing deadbolt, the new lock will almost certainly fit the same holes. If you’re adding a deadbolt where there wasn’t one, you’ll need to drill, which is doable but adds complexity.

Features that matter vs. features that don’t

Worth paying for:

• Auto-lock: Locks the door automatically after a set time. Genuinely useful.
• Activity log: Know who locked or unlocked the door and when.
• Multiple entry methods: Keypad + fingerprint + app + physical key gives you flexibility and backup options.
• Guest codes: Temporary codes for visitors, cleaners, dog walkers, etc.

Nice but not essential:

• Geofencing (auto-unlock when you approach): Works well on some locks, inconsistently on others. Don’t buy a lock specifically for this feature.
• Voice assistant integration: Convenient if you already use Alexa/Google/Siri, but not a reason to choose one lock over another.

Marketing fluff:

• “Military-grade encryption”: Meaningless marketing term. Look for the actual encryption standard (AES-128 or AES-256).
• “Unhackable”: Nothing connected to a network is unhackable. Be wary of any company that claims this.
• “Smart home of the future”: Just tell me what protocols it supports.

Battery life reality check

Manufacturer battery life claims are based on a specific number of lock/unlock cycles per day, usually 10. If your door gets more traffic than that (family of five, frequent visitors, delivery drivers), expect shorter battery life.

General ranges:

• Bluetooth-only locks: 8-12 months
• WiFi locks: 3-8 months
• Z-Wave/Zigbee locks: 8-12 months
• Thread locks: 6-10 months

Always choose a lock with a low-battery alert. Most modern locks will notify you through the app when batteries are getting low, giving you a couple weeks to swap them out.

My overall advice

• 1. Figure out your connectivity needs first. That narrows the field significantly.
• 2. Check your door measurements before ordering.
• 3. Set a realistic budget. Around $80-150 gets you a solid lock. Around $200-300 gets you premium features and build quality.
• 4. Stick with established brands that have a history of firmware updates.
• 5. Always have a backup entry method. Physical key, keypad code, something.

Smart locks have gotten genuinely good over the last few years. The reliability issues and janky apps that plagued earlier products are mostly behind us. Pick something from a reputable brand, install it properly, and you’ll wonder why you didn’t switch sooner.