If you have an expired prescription and your vision hasn't changed, you may be able to use an to renew it without a full in-person exam.
Can I Order Contacts Without a Prescription? - All About Vision
If you need contacts but don’t have a current prescription, there are legal and fast ways to get one online. 1. How to Get a Prescription Online
Guide to Buying Contact Lenses Online In the United States, it is to purchase contact lenses without a valid, verified prescription. The U.S. Food and Drug Administration (FDA) and the Federal Trade Commission (FTC) regulate contact lenses as medical devices because they rest directly on the eye. Even "decorative" or "cosmetic" lenses that do not correct vision require a prescription to ensure they fit correctly and do not cause permanent eye damage.