TempoLife › Features › Mineral water mineral content › calcium
Calcium in water
Calcium dissolved in water is absorbed about as well as the calcium in milk, which makes a hard water a real contributor for anyone who does not drink much dairy. Every water here is ranked by calcium per litre against the EFSA reference intake of 950 mg a day.
This is a reference table, not a diagnosis and not a prescription. If a clinician has put you on a sodium, calcium, potassium or fluid restriction, that number comes from them and overrides anything here. Analyses are revised as sources are re-tested, so the label on the bottle you are holding always outranks this page.
The ranking
| Water | Calcium mg/l | Share of 950 mg | “Contains calcium” | Country |
|---|---|---|---|---|
| Hepar | 555 | 58.4% | yes | France |
| Contrex | 468 | 49.3% | yes | France |
| Donat Mg | 380 | 40% | yes | Slovenia |
| Ferrarelle | 365 | 38.4% | yes | Italy |
| Gerolsteiner Sprudel | 348 | 36.6% | yes | Germany |
| Vittel | 240 | 25.3% | yes | France |
| S.Pellegrino | 208 | 21.9% | yes | Italy |
| Badoit | 190 | 20% | yes | France |
| Perrier | 147.3 | 15.5% | no | France |
| Staatlich Fachingen | 96 | 10.1% | no | Germany |
| Apollinaris | 90 | 9.5% | no | Germany |
| evian | 80 | 8.4% | no | France |
| Vichy Catalan | 60 | 6.3% | no | Spain |
| Buxton | 55 | 5.8% | no | England |
| Highland Spring | 35 | 3.7% | no | Scotland |
| Acqua Panna | 32.6 | 3.4% | no | Italy |
| Fiji Water | 18 | 1.9% | no | Fiji |
| Volvic | 11.5 | 1.2% | no | France |
| Voss | 5 | 0.5% | no | Norway |
Where the calcium comes from
Every high-calcium water on that list is a limestone or dolomite story. Rainwater carrying dissolved carbon dioxide is mildly acidic; move it slowly through calcium carbonate rock and it dissolves the rock, carrying calcium away paired with bicarbonate. Add a gypsum bed and the pairing becomes calcium sulphate instead, which dissolves far more readily and pushes the calcium figure much higher — that is the difference between a 200 mg per litre bicarbonate water and a 450 mg per litre sulphate one.
The pairing matters for how the water behaves. Calcium bicarbonate is what deposits limescale when heated, so a hard bicarbonate water is the one furring your kettle. Calcium sulphate stays in solution and does not scale much, but sulphate at high concentration has a laxative reputation of its own, which is why the highest-calcium waters are also the ones people describe as having an effect.
When water calcium is worth counting
For someone drinking milk, eating yoghurt and cheese and hitting 950 mg without thinking, a bottled water is a marginal addition. It becomes interesting in two situations. The first is a dairy-free diet, where calcium usually has to be assembled deliberately from fortified drinks, tofu set with a calcium salt, tinned fish eaten with the bones and green vegetables — a litre of a 300 mg per litre water is a third of a day and costs no planning. The second is anyone advised to raise calcium intake who finds supplements hard to tolerate.
Two cautions. Calcium is not a nutrient where more is automatically better, and the reference intake is a target rather than a floor to overshoot. And if you have had calcium kidney stones, the instinct to cut calcium is the wrong one — the stones page explains why guidelines say normal dietary calcium and lower sodium instead. For the full picture on intakes and food sources, see the calcium reference page.
Analyses: the figures each producer publishes on the label or in its technical sheet — see the basis line on every water page. Reference intakes: EFSA Dietary Reference Values. Label claims: Directive 2009/54/EC, Annex III. Mineral-water constituent limits and the fluoride labelling rule: Directive 2003/40/EC. Tap-water parametric values: Directive (EU) 2020/2184. Checked 2026-09-06.
Frequently asked questions
Which bottled water has the most calcium?
Of the waters listed here, Hepar at about 555 mg per litre — roughly 58.4% of the 950 mg adult reference intake in a single litre. The calcium-sulphate waters of the Vosges dominate the top of this list.
How much calcium do adults need?
EFSA sets a population reference intake of 950 mg a day for adults. The EU labelling reference value printed on packaging is different and lower — 800 mg — because it is a single figure chosen for labelling rather than a physiological requirement, which is why the same food can be 30% of one and 25% of the other.
Is calcium from water as well absorbed as from milk?
Studies of calcium absorption from mineral water find it comparable to milk calcium, and bicarbonate-rich waters do not appear to be worse than sulphate-rich ones. Water calcium arrives already dissolved, which helps; it also arrives without the protein, vitamin D or lactose that come with dairy.
Does hard water count towards my calcium intake?
Yes. Hardness is precisely dissolved calcium and magnesium, so a hard tap water or a hard bottled water is a small standing contribution to both. Whether it is worth counting depends on the number: a water at 20 mg per litre is noise, one at 300 mg per litre is not.
All waters compared
The full analysis table, grouped by mineral content.
Water hardness explained
Degrees, millimoles and parts per million, converted, plus what hardness does and does not do.
Low-sodium water
The 20 mg per litre label rule, and how much sodium a litre of each water really carries.
Water highest in magnesium
Every water ranked by magnesium, against the EFSA adequate intake.
Bicarbonate and alkaline water
What bicarbonate is, which waters carry a lot of it, and what it comes packaged with.
Fluoride in bottled water
The EU limit, the under-sevens labelling rule, and where natural fluoride comes from.
Count calcium from everything, not just dairy
TempoLife adds up calcium across your whole log — food, drinks and water — against the reference intake.