Getting contact lenses starts with a contact lens exam and fitting, which is a separate appointment from a standard eye exam. You’ll need a valid contact lens prescription before you can buy lenses anywhere, and that prescription includes measurements specific to your eye’s shape, not just your vision correction. The whole process, from first appointment to wearing your lenses home, typically takes one to two visits.
The Contact Lens Exam and Fitting
Even if you already wear glasses, you’ll need a dedicated contact lens fitting. A glasses prescription and a contact lens prescription are different: contacts sit directly on your eye, so your doctor needs additional measurements beyond your vision correction.
The appointment starts with a standard eye health check. Your optometrist will look for conditions like dry eye or allergies that could affect how well you tolerate lenses. From there, the fitting follows a specific sequence:
- Corneal curvature measurement. A device called a keratometer (or a more detailed corneal topographer) maps the shape of your cornea. This determines the “base curve” of your lenses, which typically falls between 8.0 and 10.0 mm. A lens that doesn’t match your cornea’s curve can press too tightly, restricting oxygen, or slide around and blur your vision.
- Tear film evaluation. Your doctor checks how much moisture your eyes produce and how stable it is. If your eyes run dry, certain lens materials or wearing schedules will work better for you.
- Trial lenses. Based on your measurements, you’ll try on a pair of lenses in the office. After wearing them briefly, your doctor re-examines the fit, watching how the lenses move and center on your eyes.
- Insertion and removal training. If you’re a first-time wearer, expect to spend time learning how to put lenses in, take them out, and clean them. This is the part most new wearers are nervous about, and it’s completely normal for it to take 15 to 30 minutes of practice.
A follow-up appointment is usually scheduled one to two weeks later. Your doctor will check how your eyes are adjusting, whether the lenses are still fitting properly, and whether your vision needs fine-tuning. Some people go through two or three trial lens brands before finding the right one.
Your Prescription and Your Rights
Once the fitting is complete, your optometrist is legally required to hand you a copy of your contact lens prescription, even if you don’t ask for it. Federal law (the FTC’s Contact Lens Rule) makes this clear: your doctor cannot charge you extra for the prescription itself, require you to buy lenses from their office, or ask you to sign a waiver before releasing it.
A contact lens prescription must be valid for at least one year. Some states require longer. Your doctor can set a shorter expiration only if there’s a documented medical reason. Once you have the prescription in hand, you’re free to buy lenses wherever you find the best price, whether that’s your eye doctor’s office, a big-box retailer, or an online seller. If you order from a third party, that seller can request verification from your prescriber, who must respond within 40 business hours.
Choosing a Lens Type
Most new wearers end up in soft lenses, which come in two main materials. Standard hydrogel lenses have been around for decades and work well for many people. Silicone hydrogel lenses are newer and allow more oxygen to pass through to your cornea, which matters most if you wear lenses for long hours. Despite the material difference, a large review of seven clinical trials involving over 1,300 people found no clear difference in comfort between the two for daily disposable wear.
The bigger choice is your replacement schedule:
- Daily disposables. You open a fresh pair each morning and throw them away at night. No cleaning routine, no lens case. A box of 30 typically costs $25 to $40, so you’re spending roughly $1 per lens or less.
- Monthly lenses. You clean and store the same pair each night, replacing them after about 30 days. A box of six lenses runs $30 to $40, with each lens costing $3 to $4. You’ll also need to buy solution.
Dailies cost more over a year but are simpler and lower-risk for infections. Monthlies are cheaper up front but demand a consistent cleaning routine.
Lenses for Astigmatism, Presbyopia, or Irregular Corneas
If you have more than about 1.0 diopter of astigmatism, standard spherical lenses won’t fully correct your vision. Toric lenses are designed with different powers along different axes to compensate, and they use stabilization features to keep the lens oriented correctly as you blink.
If you’re over 40 and struggling with close-up vision (presbyopia), multifocal contact lenses blend distance and near correction into one lens. Some doctors instead use a “monovision” approach, fitting one eye for distance and the other for reading.
For conditions like keratoconus, where the cornea has an irregular shape, rigid gas-permeable lenses or scleral lenses provide sharper vision than soft lenses can. Scleral lenses vault over the entire cornea and rest on the white of the eye, creating a smooth optical surface over even significantly distorted corneas.
Where to Buy Contact Lenses
You have several options once you have a prescription. Your eye doctor’s office typically stocks lenses and may offer manufacturer rebates. Online retailers like 1-800 Contacts, Lens.com, or retailers like Costco and Walmart often compete on price, especially for popular brands. Price-compare across at least two or three sources, since the same box of lenses can vary by $10 to $20 depending on the seller.
When ordering, you’ll need the exact information from your prescription: the brand name, lens power, base curve, and diameter. For toric lenses, you’ll also need the cylinder and axis values. Substituting a different brand or base curve without your doctor’s approval isn’t just inadvisable, it’s not permitted under most prescription rules.
Habits That Protect Your Eyes
Contact lenses are safe when used properly, but poor hygiene raises infection risk significantly. A study published in BMJ Open Ophthalmology found that sleeping in lenses triples the risk of microbial keratitis, a painful corneal infection that can permanently damage vision. Showering while wearing contacts also triples the risk, and showering daily in lenses increases it by over seven times compared to never showering in them. Water, even clean tap water, carries microorganisms that cling to lens surfaces.
The basics that matter most: wash and dry your hands before touching your lenses, never top off old solution in your case (dump it out and refill fresh), replace your lens case every one to three months, and stick to your prescribed replacement schedule. If a daily lens is meant to be thrown away at the end of the day, stretching it to two or three days saves pennies but dramatically increases your exposure to bacteria and protein buildup.
If you notice persistent redness, pain, light sensitivity, or sudden blurry vision while wearing contacts, remove them. These can be early signs of a corneal infection that needs prompt treatment.