How often
How often should you replace a contact lens case?
With each new bottle of solution, about every 1–2 months
A dirty case is a common way to reinfect lenses. Pair a new case with each bottle of solution, and never top up old fluid.
Signs it is worn out — save it nowSave one of these

Contact lens solution
Every 2 months

Renu Multi-Purpose Contact Lens Solution, 4 x 240 ml, Lens Case Included
Every 2 months

Biotrue Multi-Purpose Contact Lens Solution, 1 x 300 ml, Lens Case In…
Every 2 months
Why replace it
Biofilm builds on case walls even when they look clear. Fresh solution in a stale case undoes the hygiene step.
Signs it is worn out
- The case is cloudy or cracked
- The cap threads smell
- You have finished a bottle without changing the case
Source: Typical optician advice: new case with each bottle. As an Amazon Associate I earn from qualifying purchases.
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