Can you get an eye test while wearing contact lenses?

You can walk into the store wearing them. You cannot have your prescription measured through them.

This catches people out constantly. You book an appointment on a lunch break, arrive in your monthlies because that is what you wear to work, and then find out the numbers taken that day may not be the numbers you want cut into your glasses. A little planning avoids the whole problem.

Why the lenses have to come out

A contact lens sits directly on the tear film, on the front surface of your eye. While it is there, it is part of the optical system being measured. Take a reading through it and you are measuring the lens as much as the eye.

There is a second reason. Contact lenses rest against the cornea all day, and the cornea responds. With soft lenses the effect is usually small and settles quickly. With rigid gas permeable lenses the shaping is far more significant, and it takes longer to relax back to its natural shape.

How long to leave them out

• Soft lenses, daily or monthly. Often it is enough to take them out on arrival, though a few hours out beforehand gives a cleaner reading. If you can wear your glasses that morning, do.
• Rigid gas permeable or hard lenses. Considerably longer, and the exact number depends on how many years you have worn them. This is a decision for your optometrist, not a rule you can look up. Call ahead and ask before you plan the appointment.
• Orthokeratology lenses. These are designed to reshape the cornea overnight. A spectacle refraction has to wait until that reshaping has fully reversed. Again, ask first.

If you have worn soft lenses for years and have never gone a full day without them, mention that. It changes what your optometrist expects to see.

What to bring with you

• Your glasses, so you can drive or commute home after the lenses come out
• Your lens case and solution
• The box or the foil from your current lenses, which carries the power, base curve and diameter
• Your last prescription if you have it

Come without them if any of this is happening

Redness, pain, discharge, light sensitivity, or a lens that has felt wrong for more than a day. Take the lenses out, keep them out, wear your glasses, and tell the team what has been going on when you arrive. Do not put a lens back in to get through the appointment.

Your contact lens grade is a separate number

A spectacle prescription and a contact lens prescription are not interchangeable. A contact lens sits on the eye; a spectacle lens sits about 12mm in front of it, and that distance changes the power needed, more so at stronger grades. A contact lens prescription also includes a base curve and diameter that a spectacle prescription has no reason to carry.

So if you want both glasses and contacts, you need a refraction for the glasses and a contact lens fitting for the lenses. They are two pieces of work, done in the same visit.

Book the exam, then get the numbers cut properly

Book a Vision7 eye test at your nearest Vision Express store and tell the team you wear contact lenses when you book. The seven-step exam runs objective and subjective refraction on your uncovered eyes, checks how the two work together, and looks at the health of the front surface that your lenses have been sitting on all this time.

Once you have a clean spectacle number, ask for Shamir Opulens Exact at the counter. It is made to your measurements rather than pulled from a stock tray, which is what you want when the whole point of the visit was getting the grade right. If you need a pair the same day so you have something to wear while your lenses stay out, Opulens Advanced 1.60 is in stock and ready in 20 minutes.

Contact lens fittings are done in store. Every pair of glasses comes with free lifetime ultrasonic cleaning, free lifetime custom fitting and adjustment, and a 1-year warranty.