NHS Sight Test vs NHS Optical Voucher: What’s the Difference?

It’s easy to assume that if you qualify for a free NHS sight test, you automatically qualify for help with the cost of glasses too. You don’t. These are two separate entitlements with separate eligibility rules, and genuinely, you can qualify for one without the other.

GOS1: The Free NHS Sight Test

GOS1 is the form used when you’re entitled to a free NHS-funded sight test itself, the actual eye examination. Eligibility here is based on things like age (under 16, or 16-18 in full-time education, or over 60), certain medical conditions (diabetes, glaucoma, or a family history of glaucoma over 40), and specific benefits.

GOS3: The NHS Optical Voucher

GOS3 is a completely separate form, the actual voucher toward the cost of glasses or contact lenses, issued after your eye test if you’re eligible. It has a cash value based on your prescription strength. For the full voucher value breakdown and how to use it, see our NHS Vouchers page.

Why You Can Qualify for One But Not the Other

The eligibility criteria for these two genuinely differ. For example, being over 60 gets you a free sight test, but doesn’t on its own get you an optical voucher toward glasses, those are assessed separately, often based on income or specific benefits like Universal Credit. This catches people out: they get a free eye test, then are surprised to be asked to pay full price for their glasses afterward.

A Real Example: Sarah’s Story

Say Sarah is 62. Because of her age, she’s automatically entitled to a free NHS sight test, no income check needed. At her appointment, her optician also checks whether she qualifies for an NHS optical voucher toward glasses, and that’s assessed separately, usually based on income or specific benefits rather than age alone. If Sarah doesn’t receive a qualifying benefit, she gets her eye test for free but pays full price for her glasses. If she does, she gets both the test and a voucher toward the cost. Same appointment, two different outcomes depending on which entitlement she actually meets.

Common Questions About Sight Tests and Optical Vouchers

• If I get a free eye test, does that mean I automatically get help with glasses too? No. They’re assessed separately, as covered above.
• Can I get an optical voucher without a free sight test? In practice, no, you need a GOS3 voucher issued following an eye test, but you may have paid for that test privately if you didn’t qualify for a free one, and still be entitled to a voucher if you separately qualify.
• Does the voucher cover my whole pair of glasses? Not necessarily, it covers a set amount depending on your prescription strength. If your glasses cost more than the voucher, you pay the difference. See our NHS Vouchers page for the exact values.

NHS Sight Test: How to Know What You’re Entitled To

The honest answer is: ask your optician directly when you book, they’ll check both entitlements separately as part of your appointment. You can also check the official NHS guidance on free eye tests and optical vouchers beforehand. If you’re claiming based on Universal Credit specifically, see our guide to Universal Credit and free glasses for the exact earnings thresholds that apply.