Does homeowners insurance cover sill plate?

Answer 1

If the sill plate suffered damage due to a covered peril such as Wind, Hail, Fire, etc it would be covered subject to your deductible.

In most cases, The location of a sill plate would not subject it to a natural peril. A sill plate would normally only need replacement due to normal wear and tear which is a maintenance issue and would not be covered under your home insurance policy.