Along with your new mattress, you’ll want to purchase a moisture-resistant mattress protector that will help protect the surface of your mattress and keep it clean and free of moisture and stains. The body loses a lot of water in the form of sweat during the night, and you’ll want to protect the surface of your mattress from this moisture, particularly as surface stains may invalidate your warranty.
Mattress protectors are designed to go directly on the mattress, underneath the fitted sheet. Some mattress protectors come with a layer of quilted padding. Others are designed to keep out mites and bedbugs. Some fit over the top and sides of the mattress much like a fitted sheet, while others encase the mattress completely and close with a zipper. Protectors, sometimes called covers, can be made of waterproof materials like vinyl (recommended if incontinence is an issue) or of breathable fabrics like cotton. Choose a mattress protector whose construction and materials suit your needs. Mattress depths vary, so check to be sure the cover you choose will fit the size and the depth of your mattress.
Note that the term “mattress pad” is often used interchangeably to mean either a mattress protector—which may or may not have a layer of padding—or a mattress topper, whose purpose is to add a layer of comfort. You will definitely want a mattress protector; whether or not you choose a mattress topper as well depends on your mattress and your personal comfort preference.