Hi
To check your service and support coverage, enter the Apple Watch's serial number here:
- Check Your Service and Support Coverage - Apple Support
- Find the serial number for your Apple Watch - Apple Support
However, unless the issue is due to a manufacturing defect, cosmetic damage - including scratches - is not covered under either Apple's Limited Warranty or AppleCare+.
If the scratch is on the screen, then note also that Apple does not offer a screen repair or replacement service for Apple Watch and Apple Watch is not user-serviceable. The watch may instead be eligible for whole unit replacement via chargeable, out-of-warranty service.
I suggest that you contact Apple Support (mail-in service may be available), make a Genius Bar reservation or visit an Apple Authorised Service Provider with a view to having your watch inspected and to establish any available service options, likely timescales and cost:
- US: Apple Watch Service Answer Center - Apple Support
- Elsewhere: Select your country for Apple Watch service and repair information
Note that, whether you have scratched the screen or case, Apple does not recommend using cleaning products or polishing or buffing the watch with abrasives; these will wear away the coatings, may (further) scratch the watch and may even affect functionality as Apple Watch is manufactured with extreme precision:
A good quality screen protector (of the thin film type) may be effective in obscuring or reducing the visibility of any mark on the screen mark, as well as in providing some measure of protection against future damage.