How often should I change the batteries in a smart lock?

Change them when the lock tells you to

There is no honest single interval, because battery life depends on the lock, the cells, how often the door is used and how well the door and frame line up. The reliable rule is to change the batteries when the lock warns you. Schlage says its smart locks are designed to provide low-battery alerts before the batteries die, and depending on the model you may get app notifications or see a low-battery indicator on the lock.^[2]

Do not ignore that first warning. It exists to give you time to replace the batteries and keep keyless entry reliable.^[2] Put a reminder in your phone the day you see it, and replace all the cells at once.

Build a simple routine

Check the app or the lock's indicator on a fixed date, such as the first of each month or when you change smoke detector batteries. Some people also test the lock from outside with the door closed after any long trip.

After each change, write the date on a piece of tape inside the battery cover or in your phone. After two changes you will have a real number for your own door, which beats any manufacturer average. If a set lasts much less than the one before, treat it as a sign something has changed, and read why smart lock batteries die so fast.

Use the right batteries

Use the type your manual names. The Schlage Sense manual calls for four high-quality alkaline AA batteries and says lithium batteries may cause undesirable operation.^[1] Replace the whole set together with fresh cells from the same pack, not a mix of new and half-used ones.

Follow the manual's order of work, too. The Sense manual warns against installing batteries before the lock is mounted,^[1] and it carries an electrostatic discharge warning: touching the circuit board may damage the lock.^[1] Handle only the battery tray and connector.

Keep a way in

Before the batteries are low, know your fallback. Schlage says all its electronic locks offer backup access with either a physical key or a jumpstart port for temporary power backup.^[2] Keep a key somewhere you can reach it without the lock, such as with a trusted neighbour or in your car, and learn where the jumpstart contacts are on your model.

Keep the door in good shape

A lock that works smoothly uses less power. Schlage notes that the bolt on its lock is extended automatically, so the door and frame need to stay aligned.^[1] Once or twice a year, and especially after the humid months, check that you can lock the door without pushing, pulling or lifting it.^[1] A stiff door and a worn set of batteries are a common pair.

Dispose of old batteries properly

The EPA says that in most communities alkaline and zinc carbon batteries can be safely put in your household trash, but it recommends sending them to battery recyclers or checking with your local or state solid waste authority.^[3] The EPA says not to put button-cell, coin or lithium single-use batteries in the trash or municipal recycling bins. Store spent lithium cells with their terminals taped or each in its own plastic bag, because a lithium battery may spark and cause fires if damaged or the terminal ends touch.^[3] Button or coin cells can be a swallowing hazard, so keep them out of the reach of young children.^[3]

Stop and call a pro if

• The lock acts up on fresh batteries. If the keypad will not light, Schlage's guidance is to install fresh batteries and make sure the battery connector is connected.^[1] If it still fails, contact the manufacturer or a locksmith.
• The bolt will not extend smoothly. A door that rubs or has dropped needs adjusting by a carpenter or handyman.
• You are locked out. Try the key or jumpstart port, then call a locksmith. Do not force the lock.

Related

See how to install a smart lock, how much a smart lock costs installed in Virginia and are smart locks safe. Browse all smart home answers or the smart home guide.

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