Eye prescriptions for glasses are typically valid for one to two years, depending on your state. Contact lens prescriptions follow a stricter federal rule: they expire after one year. The difference matters because it affects when you can reorder lenses and when you’ll need a new exam.
Glasses vs. Contact Lens Prescriptions
There is no federal expiration date for eyeglass prescriptions. The FTC considered adding one but ultimately decided not to. Instead, expiration periods for glasses are set by individual states, and most set the window at one or two years. Your eye doctor may also set a shorter timeframe based on your specific eye health.
Contact lens prescriptions are different. Under the Fairness to Contact Lens Consumers Act, enforced by the FTC, a contact lens prescription expires one year from its issue date unless state law sets a longer period. If a state tries to set an expiration shorter than one year, the federal one-year minimum overrides it. A prescriber can also set a shorter expiration for a legitimate medical reason, such as a condition that requires closer monitoring.
The reason contact lenses have a stricter standard is straightforward: they sit directly on your eye. An outdated prescription or poorly fitting lens can cause real damage over time, so federal law ensures you’re checked at least once a year.
Your Right to Your Prescription
Federal law requires your eye care provider to give you a copy of your prescription after an exam, whether you ask for it or not. They cannot make the release conditional on buying lenses from their office. This applies to both glasses and contacts.
For contacts specifically, you can take that prescription to any seller, including online retailers. The seller is required to verify the prescription with your prescriber before dispensing, but your prescriber cannot block the sale simply because you’re shopping elsewhere.
How Often You Actually Need an Exam
Prescription expiration dates are legal minimums, not medical recommendations. The American Optometric Association’s guidelines suggest a schedule based on your age and risk level.
Adults aged 18 to 64 with no risk factors should have a comprehensive eye exam at least every two years. If you’re 65 or older, that shifts to every year. Anyone at higher risk, regardless of age, should go annually or more often as their eye doctor recommends. Risk factors include diabetes, a family history of glaucoma, high blood pressure, or a history of eye injuries.
For children, the AOA recommends exams at 6 to 12 months of age, at least once between ages 3 and 5, and then annually starting before first grade. Children’s vision changes rapidly, and undetected problems can affect learning and development in ways that aren’t always obvious.
When Prescriptions Expire Sooner
Certain health conditions can shorten the useful life of your prescription well before the legal expiration date. Diabetes is the most common example. The American Diabetes Association and the American Academy of Ophthalmology recommend dilated eye exams at least once a year for all people with diabetes. For those with moderate diabetic eye disease, exams every 6 to 12 months are recommended. Severe cases call for follow-up every 2 to 4 months.
Diabetes can cause blood vessels in the retina to leak or grow abnormally, and these changes can shift your vision between appointments. A prescription that was accurate three months ago may no longer correct your vision well. Glaucoma, cataracts, and other eye conditions similarly warrant more frequent monitoring, and your doctor may issue a prescription with a shorter expiration to reflect that.
Pregnancy can also temporarily change your vision due to fluid retention and hormonal shifts. If you notice your glasses or contacts aren’t working as well during pregnancy, it’s worth getting rechecked, though many doctors recommend waiting until after delivery to update your prescription since the changes often reverse.
Risks of Using an Outdated Prescription
Wearing glasses with an outdated prescription isn’t dangerous in a medical sense. You won’t damage your eyes. But you may experience headaches, eye strain, and fatigue, especially during tasks like reading or driving. If your vision has changed enough, an old prescription simply won’t help you see clearly.
Expired contact lenses are a different story. Contacts that have passed their expiration date lose oxygen permeability, meaning less oxygen reaches your cornea. This can lead to dryness, irritation, and corneal abrasions (tiny scratches on the surface of your eye). Those scratches may cause swelling, pain, and in serious cases, vision impairment.
Infections are the bigger concern. Expired contacts are more likely to harbor bacteria, which can cause pink eye, bacterial infections of the cornea, and inflammation of the eyelids. These range from uncomfortable to genuinely sight-threatening. Using contacts beyond their prescribed schedule, whether that’s daily, biweekly, or monthly, carries similar risks even if the prescription itself hasn’t technically expired.
What to Do When Your Prescription Expires
If your glasses prescription has expired and your vision still feels fine, you can keep wearing your current pair until your next exam. You just won’t be able to order new lenses until you get an updated prescription. If you notice any change in how well you see, that’s a good signal to schedule an appointment sooner rather than later.
For contacts, you won’t be able to reorder once your prescription lapses. Online retailers and optical shops are required to verify a valid prescription before selling you lenses. Planning ahead helps: if you know your prescription expires next month and you’re running low on lenses, schedule your exam before you run out rather than after.