Countertop reverse osmosis cost calculator
Last reviewed 2026-09-25.
At 2 gallons of filtered water a day for 3 years, an AquaTru Classic needs 3 one-year filter packs and 1 RO filter beyond the filters in the box, on the schedule AquaTru publishes. The total is the system price plus those parts at today's prices; enter them below. The price tag is only the start: each filter is changed at its months or its gallons, whichever comes first, and heavy use reaches the gallon limit sooner.
cost = system price + each replacement part × how many are bought over the period. Filters in the box are counted once. A filter with no gallon rating is changed on time only, so its count is "at least".
Calculator
Without JavaScript the calculator does not run; the filter counts below are complete.
Worked example: the AquaTru Classic at 2 gallons a day for 3 years
- Pre/Carbon filter AT2001 (stages 1-2): 600 gallons at 2 a day lasts 9.9 months, so it is changed every 6.0 months; 36 months need 6, one is in the box, 5 bought.
- VOC Carbon filter AT2003 (stage 4): 600 gallons at 2 a day lasts 9.9 months, so it is changed every 9.9 months; 36 months need 4, one is in the box, 3 bought.
- Reverse-osmosis membrane AT2002 (stage 3): 1,200 gallons at 2 a day lasts 19.7 months, so it is changed every 19.7 months; 36 months need 2, one is in the box, 1 bought.
AquaTru's one-year pack holds two pre-filters and one VOC filter, so the packs needed are whichever filter runs out of packs first; the RO filter is bought separately. Total = system price + 3 × pack price + 1 × RO filter price.
Filters to buy, all three systems
| System | 1 gal/day, 3 years | 2 gal/day, 3 years | 5 gal/day, 3 years | 2 gal/day, 5 years |
|---|---|---|---|---|
| AquaTru Classic | 3 one-year filter packs and 1 RO filter | 3 one-year filter packs and 1 RO filter | 9 one-year filter packs and 4 RO filters | 6 one-year filter packs and 3 RO filters |
| Bluevua RO100ROPOT-Lite | at least 2 5-in-1 filters | at least 2 5-in-1 filters | at least 2 5-in-1 filters | at least 4 5-in-1 filters |
| Waterdrop M6SL | at least 2 WD-M6RFL filters | at least 2 WD-M6RFL filters | at least 2 WD-M6RFL filters | at least 4 WD-M6RFL filters |
The Bluevua and Waterdrop counts are the least certain at high use: neither maker gives a gallon rating, and their filter indicators may call for a change well before 12 months. Treat them as floors.
Filter schedules
- AquaTru Classic: Pre/Carbon filter AT2001 (stages 1-2): 6 months or 600 gallons, whichever comes first; VOC Carbon filter AT2003 (stage 4): 12 months or 600 gallons, whichever comes first; Reverse-osmosis membrane AT2002 (stage 3): 24 months or 1,200 gallons, whichever comes first (AquaTru performance data sheet: each filter is replaced at its months or gallons, whichever comes first).
- Bluevua RO100ROPOT-Lite: RO Five-In-One filter: 12 months or no gallon rating stated (Bluevua user manual: every 12 months, or sooner when the filter life indicator says so; no gallon rating is stated).
- Waterdrop M6SL: WD-M6RFL filter: 12 months or no gallon rating stated (Waterdrop user manual: every 12 months, or when the filter light stays on; no gallon rating is stated).
Replacement parts
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| Part | Buy |
|---|---|
| AquaTru Classic one-year filter pack (2 Pre/Carbon + 1 VOC) | Amazon ↗ |
| AquaTru reverse-osmosis filter, stage 3 (Classic) | Amazon ↗ |
| Bluevua 5-in-1 RO filter for the RO100ROPOT-Lite | Amazon ↗ |
| Waterdrop WD-M6RFL filter for the M6SL | named, not linked |
Prices are not shown: Amazon prices change and may only be displayed from Amazon's own feed. Check the listing for the current price; the calculator totals the prices you enter. Tap water and electricity are not counted.
Which systems are certified for what: three countertop RO systems compared.
We do not test filters — we index what accredited certifiers publish, with attribution, and make no health or treatment claims. A certification covers a specific model against a specific standard; it is not a general seal of quality. We are not affiliated with NSF International.
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