2024-06-15
The daily vs monthly contact lens debate comes up in almost every fitting appointment. Patients assume dailies are significantly more expensive, and they are often surprised when we run the actual numbers. The cost difference is real, but it is smaller than most people think once you factor in everything. And cost is only part of the equation.
Let us do the honest math and then talk about what each option is actually best for.
The Actual Numbers (Canadian Prices, 2024)
We will use mainstream brand lenses at typical Canadian retail prices. Your exact costs will vary depending on the brand, your prescription, and where you buy, but these ratios are representative.
Monthly Lenses
| Item | Cost |
|---|---|
| Monthly lenses (e.g., Air Optix Aqua), 6-month supply per eye | $130 - $170 |
| Annual lens cost (both eyes, 12 months) | $260 - $340 |
| Multipurpose solution (~1 bottle/month at $12-15) | $144 - $180/year |
| Lens case replacement (every 3 months, often free with solution) | $0 - $12/year |
| Total annual cost | $404 - $532 |
Daily Disposable Lenses
| Item | Cost |
|---|---|
| Daily lenses (e.g., Acuvue Oasys 1-Day), 90-pack per eye | $200 - $270 |
| Annual lens cost (both eyes, 4 boxes of 90) | $800 - $1,080 |
| Solution | $0 (no cleaning needed) |
| Total annual cost | $800 - $1,080 |
So yes, daily disposables cost roughly double what monthly lenses cost per year. For a standard spherical prescription, you are looking at roughly $400 to $500 more annually for the convenience of dailies.
But that headline number is misleading if you stop there.
The Hidden Costs That Change the Math
Monthly Lens Wearers Replace Lenses Early
In theory, a monthly lens lasts 30 days. In practice, most wearers do not get a full month out of every lens. Lenses tear, fall out, or get so uncomfortable by week three that they get thrown away early. Studies show the average monthly lens wearer uses about 15 to 18 lenses per eye per year, not the theoretical 12. That bumps the actual lens cost up by 25 to 50%.
Solution Gets Wasted
People use more solution than they need, bottles expire before they are finished, or the solution gets contaminated. The $144 to $180 estimate assumes efficient use. Real-world spending on solution is often higher.
Dailies Do Not Penalize Part-Time Wear
This is the sleeper advantage of daily lenses. If you only wear contacts 4 days a week instead of 7, your daily lens cost drops proportionally. You use 208 lenses per eye per year instead of 365. At roughly $0.80 to $1.00 per lens, your annual cost drops to $330 to $416 per eye, which starts approaching monthly lens territory.
Monthly lenses cost the same whether you wear them 7 days a week or 3. You open the blister pack on day one, and 30 days later it goes in the garbage regardless.
Adjusted Comparison for Part-Time Wearers (4 days/week)
| Schedule | Monthly Lenses | Daily Disposables |
|---|---|---|
| Full time (7 days/week) | $404 - $532/year | $800 - $1,080/year |
| Part time (4 days/week) | $404 - $532/year | $460 - $620/year |
| Weekends only (2 days/week) | $404 - $532/year | $230 - $310/year |
If you only wear contacts a few times a week, daily disposables can actually be cheaper than monthly lenses.
Beyond Cost: The Practical Differences
Infection Risk
This is not a scare tactic. The data is clear: daily disposable lenses carry a lower risk of microbial keratitis (corneal infection) than reusable lenses. The biggest risk factor for contact lens infections is overnight wear and poor lens case hygiene, both of which are eliminated with dailies. You cannot sleep in a lens you threw away, and you do not need a case.
Monthly lenses are perfectly safe when used properly. But "when used properly" is doing a lot of heavy lifting in that sentence. Studies consistently show that a large percentage of monthly lens wearers do not comply with cleaning protocols, top off old solution instead of replacing it, or keep their lens case too long. Dailies remove the opportunity for those mistakes.
End-of-Day Comfort
A fresh daily lens at 7 AM is more comfortable at 7 PM than a three-week-old monthly lens. This is because protein and lipid deposits accumulate on reusable lenses even with good cleaning, and these deposits reduce wettability. Some patients who struggle with monthly lenses by mid-afternoon find that switching to dailies extends their comfortable wearing time by several hours.
Convenience
Daily lenses require zero maintenance. No cleaning routine, no solution bottles to remember when traveling, no case to keep clean. You open a blister, insert, wear, and throw away. For busy people, travellers, or anyone who simply does not want to deal with a cleaning routine, the convenience is real and worth something.
Environmental Consideration
Dailies produce more packaging waste. Each lens comes in its own blister pack, which means 730 blisters per year for a full-time daily wearer vs 24 for monthly lenses. If environmental impact matters to you, this is worth factoring in. Some manufacturers have recycling programs for blister packs, but adoption is still low.
The Hybrid Approach Nobody Talks About
Some of our patients use monthly lenses as their primary option and keep a box of dailies for specific situations: travel, sports, camping, nights out. You get the cost savings of monthlies most of the time and the convenience of dailies when you need it. This works as long as your optometrist fits you for both types, since the prescriptions are often different (different base curves and diameters).
When Monthly Makes More Sense
- You wear contacts 6 to 7 days a week and budget is a real constraint
- You are diligent about cleaning and lens case hygiene
- You have a complex prescription (high astigmatism, multifocal) where daily options are limited or very expensive
- Environmental waste concerns you
When Daily Makes More Sense
- You wear contacts part-time (4 days a week or less)
- You have dry eyes or allergies
- You travel frequently
- You are honest with yourself that your cleaning routine is inconsistent
- You play sports and occasionally lose or damage a lens
- End-of-day comfort is a priority
The Bottom Line
Full-time daily disposables cost more than monthly lenses. There is no getting around that. But the gap narrows significantly for part-time wearers, and closes completely for weekend-only wearers. Factor in the lower infection risk, better comfort, and zero maintenance, and dailies represent genuine value, not just convenience at a premium.
The best choice depends on how often you wear contacts, your budget, your prescription, and how honest you are about your cleaning habits. Your optometrist can help you figure out which option makes the most sense for your specific situation. There is no universally right answer.