Fluoride is added to public water supplies in Ireland by law, and it’s one of the things we get asked about most. Some people want it out of their drinking water. Others just want to know how much is in it and why. This guide sets out the facts, what Irish health authorities say, the reasons people give for removing it, and which home filters actually take it out.
Quick answer
- Is there fluoride in Irish tap water? Yes, on public supplies. Irish regulations set the level at 0.6 to 0.8 mg per litre.
- Is it safe? The Department of Health and the HSE say fluoridation at this level is safe and helps protect teeth against decay.
- Legal limit: no drinking water in Ireland may contain more than 1.5 mg of fluoride per litre.
- Private wells: not fluoridated. Any fluoride in a well is whatever occurs naturally in the ground.
- Removing it: reverse osmosis removes most fluoride. Standard carbon jug filters don’t. Removing it is a personal choice, not a health necessity.
Why is fluoride added to Irish water?
Under the Health (Fluoridation of Water Supplies) Act 1960, fluoride is added to water supplied to the public through pipes. The HSE describes it as a public health measure designed to prevent and control tooth decay. Fluoride strengthens tooth enamel, which is also why it’s in most toothpaste.
The level was lowered in 2007. Since 1 July that year, the Fluoridation of Water Supplies Regulations 2007 have required fluoridated public supplies to contain between 0.6 and 0.8 mg of fluoride per litre. Separately, the European Union (Drinking Water) Regulations 2023 set a legal maximum of 1.5 mg per litre for any drinking water, fluoridated or not.
How much fluoride is in Irish water?
| Water supply | Fluoride | Where the figure comes from |
|---|---|---|
| Public mains (fluoridated) | 0.6 to 0.8 mg/L | Fluoridation of Water Supplies Regulations 2007 |
| Legal maximum, any drinking water | 1.5 mg/L | European Union (Drinking Water) Regulations 2023 (S.I. No. 99 of 2023) |
| Private well | None added. Natural fluoride only | A lab analysis of your own water |
One milligram per litre (mg/L) is a thousandth of a gram in a litre of water, the same as one part per million. Uisce Éireann says a reading over the limit on a fluoridated supply suggests a problem with the dosing system at the treatment plant.
What Irish health authorities say
The official position is clear. The Irish Expert Body on Fluorides and Health, which advises the Department of Health, states that water fluoridation at the optimal level ‘does not cause any ill effects’ and is ‘safe and effective in protecting the oral health of all age groups’. The Department of Health’s fluoridation page, last updated in April 2025, carries the same position. The HSE says the Department keeps the policy under constant review.
The Health Research Board, Ireland’s health research agency, reviewed the evidence again in 2022, looking at health effects other than teeth. It found ‘no definitive evidence that community water fluoridation has negative health effects’. It also said the research on thyroid and on brain development (neuropsychological) outcomes was limited and inconclusive, and called for better-quality studies in those areas.
The one side effect the expert body accepts is dental fluorosis: faint white lines or patches on teeth that form when young children take in too much fluoride while their teeth are developing. It treats this as cosmetic rather than a health problem, and points out that much of the fluorosis seen comes from sources other than water, such as fluoride toothpaste.
Why some people choose to remove it
Plenty of people are happy with fluoridated water. Others would rather not have it, and these are the reasons we hear most often:
- Choice. Fluoridation applies to everyone on the supply. Some people object on principle and would rather decide for themselves.
- Total intake. Fluoride also comes from toothpaste, mouthwash and tea, and some people want more control over how much they take in overall.
- Ongoing research. In 2024 the US National Toxicology Program concluded, with moderate confidence, that drinking water containing more than 1.5 mg of fluoride per litre is linked to lower IQ in children. That is nearly twice the top of the Irish range, and the report itself said more studies are needed to understand lower exposures. Irish health authorities have not changed their advice.
- Fluorosis. Some parents want to reduce the chance of white marks on their children’s teeth.
Our view: removing fluoride is a personal choice, not a health necessity. Irish tap water is safe to drink with fluoride in it. If you do take it out of your drinking water, keep brushing with fluoride toothpaste and ask your dentist whether your family’s teeth need anything else.
How to remove fluoride from tap water
Fluoride is dissolved in the water rather than floating in it as particles, so most everyday filters let it straight through. Here’s how the common options compare.
| Method | Removes fluoride? | Notes |
|---|---|---|
| Reverse osmosis (RO) | Yes, most of it | A very fine membrane holds back dissolved minerals, fluoride included. Fitted under the sink with its own tap for drinking and cooking |
| Carbon jug filter | No | Good for chlorine taste and smell. Fluoride passes through |
| Under-sink carbon filter | No | Same as a jug: taste and chlorine, not fluoride |
| Water softener | No | Swaps the calcium and magnesium that cause limescale for sodium. Fluoride is unaffected |
| Boiling | No | The fluoride stays in the kettle and concentrates slightly as water boils off |
| Distillation | Yes | Works, but it’s slow and heavy on electricity |
Reverse osmosis is the practical choice for most homes. Water is pushed through the membrane under pressure, and most of the fluoride, along with limescale minerals, lead and other dissolved substances, is rinsed away to drain. Carbon stages before and after the membrane take care of chlorine taste and smell. We don’t quote removal percentages, because they depend on your water, your pressure and the age of the membrane, but a working RO membrane removes most of the fluoride.
The under-sink RO systems we supply and fit all remove most fluoride. Compare them on our drinking water filter page:
- 5-stage RO with storage tank: €275.99 supply only, or €399 fitted.
- EcoSoft Standard Pro: the same system plus a mineraliser that puts calcium and magnesium back for taste. €289.99 supply only, or €449 fitted.
- Aplos Angel Direct Flow: tankless and slim, for a small press. €439 supply only, or €599 fitted.
The filters are changed once a year: €89 for a DIY kit, or €150 fitted by us. For the full running costs, see our reverse osmosis cost guide.
Private wells and fluoride
Fluoridation only applies to public supplies, so if your house is on a private well, nobody adds fluoride to your water. Any fluoride in it comes naturally from the ground the water passes through. An analysis from an independent accredited lab will show the level. If it’s above the 1.5 mg per litre drinking water limit, or you’d simply like it lower, an RO system at the kitchen tap reduces it, and we specify any other treatment from the same lab report. See our well water treatment page.
Want fluoride out of your drinking water?
We supply and fit under-sink reverse osmosis systems nationwide except Donegal, Kerry, Leitrim and Sligo, where we ship supply-only. Tell us about your kitchen and we’ll recommend the right system.
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Common questions
Is Irish tap water safe to drink with fluoride in it?
Yes. The Department of Health and the HSE say fluoridation at the Irish level is safe. For a wider look at mains water quality, see is Irish tap water safe to drink?
Does a jug filter remove fluoride?
Standard carbon jug filters don’t. They improve taste and reduce chlorine, but fluoride passes through.
Does boiling water remove fluoride?
No. Boiling leaves the fluoride in the water, and as some of the water evaporates the level goes up slightly.
What else does reverse osmosis remove?
As well as fluoride, an RO membrane holds back limescale minerals, lead, nitrates and fine particles such as microplastics. It’s also one of the treatments the EPA and HSE list for reducing PFAS.
Will a mineraliser put fluoride back?
No. A mineraliser adds small amounts of calcium and magnesium for taste. It doesn’t add fluoride.
