Apple care for watch

You should know if you have it. Head to Apple's Check Your Service and Support Coverage page, and enter your device's serial number. You'll find out how much time you have left on your AppleCare plan, and if you can still buy AppleCare+ for this device.

Hi!

An easy way to check is to go to this link, Check Your Service and Support Coverage - Apple Support and enter the Serial Number of the device you are curious about!

Hope this solves your question.