Health information, not medical advice. Test your own water and speak to your dentist or local health authority about fluoride. We may earn a commission when you buy through our links; it never affects our scores.
Does reverse osmosis remove fluoride?
Yes. Reverse osmosis removes most of the fluoride in tap water, and systems certified for it under NSF/ANSI 58 are tested to cut fluoride from 8 mg/L to 1.5 mg/L or less. Certified systems that publish an average report 90% to 96% reduction. Fluoride is an optional claim under NSF/ANSI 58, though, so check that the system you buy lists it.
How does reverse osmosis remove fluoride?
Fluoride in water is a dissolved ion. An RO membrane lets water molecules through under pressure and rejects most dissolved ions, which are flushed to the drain. The carbon filters in an RO system do little for fluoride on their own; the membrane does the work. That’s why a worn or damaged membrane lets more fluoride through, and why the membrane has its own replacement schedule.
How much fluoride does reverse osmosis remove?
For a fluoride claim under NSF/ANSI 58, the certifier runs water with 8 mg/L of fluoride through the system and the treated water must come out at 1.5 mg/L or less. That’s at least about 81% reduction. The test water holds far more fluoride than tap water does, about 11 times the 0.7 mg/L used in fluoridation, so it’s a stress test. Here’s what certified systems report:
| System | Type | Certified by | Average fluoride reduction |
|---|---|---|---|
| AquaTru Carafe | Countertop | IAPMO R&T | 96.4% |
| AquaTru Classic | Countertop | IAPMO R&T | 93.5% |
| Aquasana SmartFlow RO | Under-sink | WQA | 90% |
| Waterdrop G3P800 | Under-sink | IAPMO R&T | Certified |
| APEC RO-90 | Under-sink | WQA | Certified |
| iSpring RCC7AK-BN | Under-sink | NSF International | Certified |
Averages are from each maker’s performance data sheet for the certified model. “Certified” means the listing covers fluoride and the sheet we checked gave no average. Check the exact model number: iSpring’s certification covers the RCC7AK-BN, for example.
Do all reverse osmosis systems remove fluoride?
Most do when they’re working properly, according to the American Dental Association. But a system certified to NSF/ANSI 58 only has to prove it reduces total dissolved solids; fluoride, lead, arsenic, and the rest are optional claims. Some RO systems sold online are certified for TDS only, or not certified at all. If fluoride is the reason you’re buying, look for fluoride on the certifier’s listing for that model.
What else removes fluoride?
- Distillation: Removes most fluoride, according to the ADA, but it’s slow and uses electricity.
- Activated alumina and bone char: Some of these filters can remove significant fluoride. Check for a certified fluoride claim.
- Ion exchange pitchers: The Culligan ZeroWater is certified by IAPMO R&T for fluoride, but its filters last 20 gallons, so it costs far more per gallon than RO.
- Carbon pitchers, fridge filters, and softeners: Most don’t remove fluoride. The ADA says most carbon filters don’t, and softening doesn’t significantly change fluoride levels.
Does remineralizing RO water add fluoride back?
No. Remineralizing stages add calcium and magnesium, not fluoride. RO removes those minerals along with fluoride, which is why some systems include one. See how to remineralize water.
Should you remove fluoride from your water?
That’s a personal decision. US water systems that fluoridate aim for 0.7 mg/L, the level the US Public Health Service recommends to prevent tooth decay. In 2024, a National Toxicology Program review linked levels above 1.5 mg/L to lower IQ in children, and found insufficient data on 0.7 mg/L. If you remove fluoride, ask your dentist whether you or your children need it from another source. For infant formula, see our baby formula guide, and for the evidence in full, our fluoride guide.
Which reverse osmosis systems are certified for fluoride?
Ranked by our overall score. Every one is certified for fluoride under NSF/ANSI 58. How we score
| # | System | Score | Certified by | Lead | PFAS | Fluoride | Running cost | Price |
|---|---|---|---|---|---|---|---|---|
| 01 | AquaTru CarafeBest overall, no plumbingCountertop RO | 4.6 | IAPMO R&T | Certified | Certified | Certified | $0.33/gal | $356.25on Amazon › |
| 02 | AquaTru ClassicBigger countertop batchesCountertop RO | 4.5 | IAPMO R&T | Certified | Certified | Certified | $0.17/gal | $451.25on Amazon › |
| 03 | Waterdrop G3P800Best under-sink, tanklessUnder-sink RO | 4.3 | IAPMO R&T | Certified | Certified | Certified | About $160/yr | $849.00on Amazon › |
| 04 | APEC RO-90Certified for lessUnder-sink RO | 4.2 | WQA | Certified | No | Certified | $60 to $75/yr | $219.16on Amazon › |
| 05 | Aquasana SmartFlow ROUnder-sink, published priceUnder-sink RO | 4.1 | WQA | Certified | Certified | Certified | $0.49+/gal | $239.99on Amazon › |
| 06 | iSpring RCC7AK-BNBudget under-sinkUnder-sink RO | 3.9 | NSF International | Certified | Claim | Certified | $100 to $140/yr | $234.99on Amazon › |
Certified: Certified by an independent body (named in each pick). Lab test: Tested by a named independent lab, not certified. Claim: The maker's claim, not certified. No: No claim. PFAS means PFOA/PFOS, or Total PFAS where the pick says so.
For more options, including a pitcher, see the best water filters for fluoride.
Common questions
Does reverse osmosis remove 100% of fluoride?
No. Certified systems that publish an average report 90% to 96% reduction. At the 0.7 mg/L used in fluoridated water, that leaves under 0.1 mg/L.
Do under-sink RO systems remove fluoride?
Yes, if they’re certified for it. The Waterdrop G3P800, APEC RO-90, Aquasana SmartFlow RO, and iSpring RCC7AK-BN are all certified for fluoride under NSF/ANSI 58.
Does a Brita or PUR filter remove fluoride?
No. Neither is certified for fluoride. The Culligan ZeroWater is the pitcher certified for it. See PUR vs Brita.
Does RO remove fluoride from well water?
Yes, the same way. Natural fluoride in some wells is higher than in city water, so test first. If your well is above 1.5 mg/L, choose a system certified for fluoride and retest the filtered water.
How do I know my RO system is still removing fluoride?
Replace the membrane on schedule. A TDS meter gives a rough check: If the filtered water’s TDS rises well above its usual reading, the membrane is wearing out. For certainty, test the filtered water for fluoride.
Sources
- IAPMO R&T product listing directory (AquaTru, Waterdrop)
- WQA certified product listings (APEC, Aquasana)
- NSF International listings (iSpring)
- Aquasana SmartFlow RO performance data sheet
- California State Water Board: Example NSF/ANSI 58 performance data sheet (fluoride test levels)
- American Dental Association: Fluoridation Facts, home water treatment
- National Toxicology Program: Fluoride review (2024)
- CDC: Community water fluoridation recommendations
- AquaTru Carafe and Classic performance data sheets (IAPMO R&T)
Prices as of October 14, 2026. Product prices and availability are accurate as of the date/time indicated and are subject to change. As an Amazon Associate we earn from qualifying purchases.