In tandem with the rise of e-commerce has come the rise of eye commerce — the ability to buy eye care products online. Today, at least one-fifth of contact lens wearers in the U.S. buy their contact lenses online, and that number keeps climbing. 

Convenience and price drive many contact lens customers to turn to the internet for their purchases. But when you’re shopping for contacts online, are you eyeing more than the ease of doing business and the cost savings? If you’re not, you should be. 

Here are eight things you need to keep in mind — to give you peace of mind — when buying contacts online: 

1. Get an eye exam 

Eye care professionals urge consumers to undergo regular eye exams (typically once a year) to ensure their contact lens prescription is up to date, since the health of your eyes can change between checkups. Never buy contact lenses with an expired prescription, eye care experts say. 

According to the Federal Trade Commission (FTC), a contact lens prescription should be good for at least a year, but some states allow two-year prescriptions. Prescriptions can be written by optometrists, ophthalmologists and licensed contact lens fitters. 

“People should keep in mind that contact lenses are not harmless accessories, but are FDA-regulated medical devices with a small, but real, risk of infection and loss of vision,” says Boston ophthalmologist Dr. Deborah Jacobs, past president of the Eye and Contact Lens Association. 

By the way, the FTC notes, all contact lenses require a prescription — even cosmetic lenses designed only to alter the appearance of your eyes, rather than improve your vision. 

Businesses that sell cosmetic lenses without a copy of your prescription or without verifying your prescription information are selling them illegally, the FTC says. 

The Mayo Clinic cautions that decorative over-the-counter contacts should be avoided, as they can cause eye injuries or infections. 

“Unfortunately, many retailers are illegally selling contact lenses or using regulatory loopholes to circumvent requirements designed to ensure the safety of our patients,” the American Optometric Association warns.

SEE RELATED: Contact lens eye exams

2. Check your contact lens prescription 

Aside from the expiration date, your contact lens prescription normally should show information such as: 

• Your name
• Name of the prescriber
• Date of your eye exam
• Power of the vision correction, expressed in numbers preceded by plus or minus signs
• Curvature of the lenses
• Diameter of the lenses
• Brand name of the lenses

“If the lenses will not be dispensed by the prescribing practitioner, it is important that whoever fills the prescription does so completely and accurately,” says the GP Lens Institute, the educational arm of the Contact Lens Manufacturers Association. 

3. Be aware contacts and glasses prescriptions are different

If you have a prescription for eyeglasses, you can’t use it to buy contact lenses. You’ll need a separate prescription just for contacts. 

The main reason: Eyeglass lenses are positioned about 12 millimeters from your eyes, while contact lenses rest directly on the surface of your eyes.

SEE RELATED: How contact lenses and glasses prescriptions are different 

4. Stick to the prescribed brand

The FDA suggests being on the lookout for attempts to substitute one contact lens brand (perhaps a cheaper variety) for the one that appears on your prescription. 

“While this may be acceptable in some situations, there are differences in the water content and shape between different brands,” the FDA says. “The correct choice of which lens is right for you should be based only on an examination by your eye care professional.” 

In addition to ensuring the brand is correct, double-check whether the power and other details are right, the FDA says. If something about the lenses appears to be wrong, contact your eye care professional and the retailer. 

5. Shop around 

Prices for the exact same brand of contacts frequently vary from seller to seller. Therefore, it can pay to do some comparison shopping — you might be able to save some money. 

In addition, hunt for cost-cutting deals or coupon codes, and take a look at subscription services that sell bulk supplies of contacts.

Other ways to cut your contact lens costs: Check your vision insurance coverage for contacts and for any rebates on your contact lens purchase.

READ MORE: Best places to buy contacts in 2024

6. Ensure you always have contacts and lens care supplies

“Some contact lenses may take time to get to you, so make sure you order early enough you don’t run out,” says Mike Suh, director of contact lenses at online eyewear retailer Clearly.

No matter how many contact lenses you plan to buy, don’t select an online retailer based on price alone. You should take other factors into account, including whether you or your friends, relatives or colleagues are familiar with or have a good impression of the retailer. 

7. Check out the seller’s reputation 

Before buying contact lenses from an online retailer, do some online research. Look at customer reviews, and visit the websites of organizations like the Better Business Bureau to see whether complaints have been filed against the retailer.

“Order your contact lenses from a supplier you are familiar with and know is reliable. Contact lenses are often more complex than they appear,” the FDA advises. 

New York City ophthalmologist Dr. Michelle Rhee, president of the Eye and Contact Lens Association, cautions that some e-commerce sites might be selling contacts that are not approved by the FDA or that are counterfeit. 

Dylan Herold, a contact lens specialist at Clearly, says you also should examine a retailer’s customer service and return policies, as well as the ease of ordering, the security of the retailer’s website, and the selection of products, accessories and manufacturers. 

“A provider that only has a few products won’t be able to serve a customer’s range of needs,” Herold says. 

8. Beware of online eye exams 

Dr. Ming Wang of Wang Vision 3D Cataract and LASIK Center in Nashville recommends steering clear of online eye exams marketed by some e-commerce retailers of contact lenses. 

“These services are not likely to get someone a correct prescription and cannot diagnose eye problems that could be occurring. They are not evaluating the material and fit with how it interacts with someone’s anatomy,” Wang says.

“They are in no way a substitute for an in-person eye examination and customized contact lens fitting. Anyone who needs contact lenses should be sure to have a fitting done with a local doctor.”

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