Having a high prescription does not limit your options when buying glasses online — but it does mean there are a few more decisions to make than for a standard prescription. The right lens material, frame shape, and coatings all have a more noticeable impact at higher prescription strengths, and understanding why makes it significantly easier to order with confidence.
This guide covers everything specific to high prescription glasses — from what counts as a high prescription, to which lens options reduce thickness and weight, and which frame styles work best.
What Counts as a High Prescription?
A prescription is generally considered high when the sphere (SPH) value reaches +6.00 or above for long-sightedness, or -6.00 or below for short-sightedness. A cylinder (CYL) value of ±2.00 or more — which relates to astigmatism — also places a prescription in the higher range.
These values require lenses that bend light more significantly than standard prescriptions, which affects lens thickness, weight, and in some cases, visual distortion at the edges of the lens. Modern optical materials and lens designs address most of these challenges effectively, but choosing the right options matters more at higher prescription strengths than it does for mild corrections.
If you are unsure where your prescription sits, our guide to types of prescription lenses explains the different lens types and how prescription strength affects which options are most suitable.
Lens Material: Why High-Index Matters
The single most important decision for high prescription wearers is lens material. Standard plastic lenses bend light at a fixed rate, which means stronger prescriptions require more material to achieve the required correction — resulting in thicker, heavier lenses.
High-index lenses solve this by using materials that bend light more efficiently. The same prescription can be achieved in a significantly thinner, lighter lens. The higher the index number, the thinner the finished lens:
1.60 index — a step up from standard lenses, suitable for mild to moderate prescriptions. Offers a noticeable improvement in thickness without a large price increase.
1.67 index — a strong choice for moderate to high prescriptions. Considerably thinner and lighter than standard lenses, and appropriate for most frames.
1.74 index — the thinnest option currently available. Recommended for prescriptions at the higher end of the range, particularly where frame style or aesthetics are a priority. Produces the flattest, most lightweight lens possible for strong corrections.
At Glasses Store, lens thickness options are presented clearly at checkout based on your prescription values, so you can choose the best fit for your needs and budget.
Aspheric Lens Design
Beyond the index, the design of the lens itself makes a difference. Traditional spherical lenses have a consistent curve across the entire surface, which can cause visual distortion at the edges — sometimes described as a slight fishbowl or magnification effect — in higher prescriptions.
Aspheric lenses have a flatter, more gradual curve that reduces this distortion and produces a more natural visual experience, particularly towards the periphery of the lens. They are also thinner at the edges than equivalent spherical lenses. For anyone with a high prescription, aspheric design is worth considering alongside the index choice.
Lens Coatings for High Prescription Glasses
High-index lenses reflect more light than standard plastic lenses, which makes anti-reflective coating particularly beneficial for high prescription wearers. Without it, the increased reflectivity of a high-index lens can be distracting — both cosmetically and in terms of visual clarity.
Our guide to anti-reflective coating for glasses covers this in detail, but in summary: MAR (multi-anti-reflective) coating applied to a high-index lens dramatically reduces surface reflections, improves light transmission, and makes lenses appear almost invisible — all of which matter more at higher prescription strengths.
Scratch-resistant coating is also advisable. Thinner, high-index lenses are more vulnerable to surface marks than thicker standard lenses, so adding a hardened protective layer extends the lifespan of the lens meaningfully.
Choosing the Right Frame for a High Prescription
Frame choice has a direct impact on how thick the finished lens appears, particularly for short-sighted (minus) prescriptions where lens thickness builds towards the edges.
Smaller frames reduce the total lens diameter required, which directly reduces edge thickness. A compact rectangular or round frame will produce a noticeably thinner-looking lens than an oversized or wide frame for the same prescription.
Full-rim frames are generally recommended for high prescriptions as they conceal the lens edge entirely. Semi-rimless and rimless styles expose the edge of the lens, which draws more attention to thickness and requires stronger lens material to avoid stress and cracking at the drill points.
Rounded or oval shapes distribute edge thickness more evenly than strongly angular shapes, which can concentrate thickness at the corners. This makes round and oval frames a practical as well as stylish choice for higher prescriptions.
You can browse our full range of glasses frames and filter by shape to find styles that work well with stronger prescriptions. Both our men’s glasses and women’s glasses collections include a wide range of compact and full-rim options suitable for high prescription lenses.
Ordering High Prescription Glasses Online
The ordering process for high prescription glasses is the same as for any other prescription — choose your frame, select your lens type and thickness, add your preferred coatings, and submit your prescription at checkout. Our step-by-step guide to how to order prescription glasses online covers the full process in detail.
The key differences for high prescription wearers are:
- Lens thickness selection — take a moment to consider the index options available for your prescription strength rather than defaulting to standard
- Next-day delivery — single vision glasses with standard prescriptions qualify for next-day dispatch when ordered before 3pm. Some very high prescriptions may require additional processing time, and our team will advise if this applies to your order
- Prescription review — at Glasses Store, every prescription is reviewed by our team before glazing begins. For high prescriptions in particular, we check the values carefully and will contact you if anything needs clarifying before we proceed
Every order is backed by a 12-month frame warranty and our 90-day returns policy. If prescription glasses online do not feel right when they arrive — which can occasionally happen as eyes adjust to a new lens thickness or design — our team will work with you to resolve it.
Frequently Asked Questions
What is considered a high prescription for glasses? A prescription is generally considered high when the sphere (SPH) value is +6.00 or above, or -6.00 or below. A cylinder (CYL) value of ±2.00 or more also places a prescription in the higher range. At these levels, lens material and frame choice have a more noticeable impact on the finished pair than at lower prescription strengths.
What are the best lenses for high prescription glasses? High-index lenses — particularly 1.67 or 1.74 index — are the best choice for high prescription wearers as they produce a significantly thinner and lighter lens than standard materials for the same correction. Aspheric lens design further reduces edge thickness and peripheral distortion. Adding MAR (anti-reflective) coating is strongly recommended as high-index materials reflect more light than standard lenses.
What frame shapes are best for high prescriptions? Smaller, full-rim frames work best. Smaller frames reduce the total lens diameter required which directly reduces edge thickness, while full-rim frames conceal the lens edge entirely. Round and oval shapes distribute thickness more evenly than angular styles. Rimless and semi-rimless frames are possible with ultra-high-index lenses but require careful consideration.
Can I get varifocal lenses with a high prescription? Yes. Varifocal lenses are available for high prescriptions. High-index varifocal lenses are recommended to manage thickness, and digitally surfaced designs offer better precision and a wider clear viewing area — particularly important at higher prescription strengths where lens aberration is more noticeable.
Are high prescription glasses more expensive online than on the high street? Not necessarily. Online retailers have lower overheads than high street opticians, which means the savings are typically passed on to the customer. At Glasses Store, high-index lens options are competitively priced and clearly explained at checkout so you can choose based on your prescription strength and budget.
Is it safe to order high prescription glasses online? Yes, when you choose a retailer that reviews prescriptions before glazing and has qualified technicians producing the lenses in-house. At Glasses Store, every prescription — including high prescriptions — is checked before we begin glazing, and our team will contact you if anything needs clarifying.
Ready to Order?
At Glasses Store, high prescription glasses are available with a full range of high-index lens options, coatings, and frame styles. Browse our glasses frames and select your lens thickness and coatings at checkout. Every order is glazed in-house by qualified technicians, backed by a 12-month warranty, and covered by our 90-day returns policy.
