Aqara Smart Lock U100 vs U200 vs U300

They are not a good, better, best range

The model numbers suggest a ladder. They are not one. Each of these fits a different kind of door, so the choice is made by looking at your door rather than at your budget.

• U100 — a full deadbolt replacement for US-style doors. The whole lock comes out and the Aqara goes in.
• U200 — a retrofit. It fits over the cylinder of your existing lock, so the outside of the door is unchanged and your old keys still work.
• U300 — a lever handle set, not a deadbolt at all. This is the one for internal doors, back doors and outbuildings.

What that means in practice

The U100 is the most conventional choice and the most work to fit. Measure the backset and the door thickness first. It uses Bluetooth and Zigbee, adds straight into the Home app without an Aqara hub, and keeps a mechanical key and a USB-C emergency power port.

The U200 is the one to look at first if you rent, if the door is shared, or if other people need to keep using their existing keys. It runs on Thread, so it joins Apple Home through a HomePod mini, a HomePod or an Apple TV 4K rather than through a manufacturer hub, which usually means a faster response than Bluetooth alone. Aqara sells it in two versions, one for Euro profile and selected Scandinavian cylinders and one for US deadbolts. They are not interchangeable, so measure before ordering.

The U300 exists because a deadbolt cannot serve every door. It speaks Matter, so it needs no Aqara hub, and Aqara rates it at up to ten months on one set of batteries.

Which to buy

Look at the door, not the list.

• Existing deadbolt you are happy to replace, and US-style: U100.
• You want to keep the outside of the door and the existing keys: U200.
• A handle-and-latch door rather than a deadbolt: U300.

All three support Apple Home Key, so tap-to-unlock is not a reason to pick one over another.