Contact lens prescriptions last at least one year in the United States. That’s the federal minimum set by the Fairness to Contact Lens Consumers Act. Some states allow longer expiration periods of two years, but no state can require a shorter one. Once your prescription expires, you won’t be able to order new lenses until you get a new exam.
Federal Law Sets the Minimum
The Fairness to Contact Lens Consumers Act establishes a straightforward rule: a contact lens prescription expires on the date specified by state law, as long as that date is one year or more from the issue date. If your state doesn’t specify an expiration or sets one shorter than a year, federal law overrides it and guarantees you at least 12 months.
Your eye doctor can set a shorter expiration only if there’s a documented medical reason related to your eye health. That reason has to be recorded in your medical file, and the expiration date can’t be earlier than the date the doctor recommends for your next checkup. In practice, most prescriptions are written for one or two years depending on the state.
State-by-State Differences
Most states default to one year, but several states, including California and Massachusetts, allow contact lens prescriptions to remain valid for two years. The key distinction: if your state law says two years, that’s what you get. If it says one year or says nothing at all, you get one year under federal law. Your prescription paperwork should include the expiration date, so check the date printed on it if you’re unsure.
This is different from eyeglass prescriptions, which commonly last one to two years in most states and aren’t governed by the same federal law. Contact lenses sit directly on your cornea, which is why they carry stricter renewal requirements.
Why Contact Prescriptions Expire Faster
Contact lenses reduce oxygen flow to the surface of your eye. Over months and years of wear, this can lead to problems you won’t feel happening. Corneal swelling, tiny surface abrasions, and new blood vessel growth near the cornea can all develop without pain or obvious vision changes. An annual exam catches these issues before they become serious.
Your prescription itself can also shift. Corneal shape changes gradually over time, and a lens that fit well a year ago may no longer sit correctly on your eye. A poorly fitting lens increases the risk of infections, irritation, and corneal ulcers. The expiration date exists to make sure you’re regularly checked for both fit and eye health, not just whether you can read the bottom line of a chart.
What a Renewal Exam Involves
Renewing a contact lens prescription is not the same as a standard eye exam. A comprehensive eye exam checks your overall eye health, including dilating your pupils to examine the back of your eye, testing eye pressure for glaucoma, and evaluating peripheral vision and depth perception. A contact lens exam is narrower in scope: it focuses on your visual acuity and how well your lenses fit.
The contact lens evaluation typically involves two appointments. At the first, your doctor measures your cornea to determine the right lens size and type, tests your vision, and places trial lenses on your eyes. You then wear those lenses for a period before returning for a follow-up, where the doctor confirms the fit is comfortable and your corrected vision is accurate. Some offices combine a comprehensive exam and contact lens fitting into a single visit, but they’re technically separate services and may be billed separately.
Your Right to Your Prescription
Under federal law, your eye doctor is required to give you a copy of your contact lens prescription at the end of your fitting, whether you ask for it or not. You’re free to use that prescription at any retailer, online or in person, and your doctor cannot charge an extra fee for releasing it. Sellers can verify your prescription with your doctor, but if the doctor doesn’t respond to the verification request within a set timeframe, the seller is allowed to fill the order anyway.
This means you’re never locked into buying lenses from the office that wrote your prescription. You can shop around for the best price as long as your prescription hasn’t expired.
Outside the United States
If you live in the UK, there’s no single mandated expiration period. Optometrists set the expiry date based on their clinical judgment, factoring in the type of lens, how you wear them, and your individual eye health. The expiry date is typically aligned with when your next clinical review is due, which for most wearers falls around 12 months. Other countries vary, so check with your local provider if you’re outside the US or UK.