Filter-life estimator
How long will your filter last?
Answer one or two quick questions and we'll estimate when yours is due — using Sentry H2O's published schedule, not guesswork.
Estimates use Sentry H2O's published schedules. Educational guidance only — not health or medical advice.
Replacement filters
Find your refill in two clicks.
Pick your system — we’ll show the exact filter and the schedule it needs. Subscribe and we’ll handle it from there.
All replacement filters
Not sure which system you have? Send us a photo and we’ll identify it.