Best Magnesium Citrate Supplements 2026: Cost per Effective Dose
The best magnesium citrate is Nature Made Magnesium Citrate: 250 mg of magnesium in 2 softgels, USP Verified, $0.39 a day at list price. The 3 citrates we score cost $0.24 to $0.47 per 300 mg of magnesium. The cheapest at list price, NOW, is on no testing list and its serving is over the daily limit.
Top pick for magnesium citrate
Nature Made Magnesium Citrate 250 mg
250 mg of magnesium per 2 softgels, on USP Verified, $0.39 a day at Nature Made’s list price. It is the only citrate we score that an outside program checks, and one serving stays under the daily limit.
Check price on AmazonHow it fits our overall pick: we lead with Nature Made Magnesium Glycinate (200 mg, USP Verified, $0.73 a day) because it is on USP’s list and glycinate was better tolerated than oxide in a small trial (Schuette 1994). This citrate is the lower-cost tested option: $0.47 against $1.10 per 300 mg at brand list prices (prices on Amazon differ). Our magnesium picks.
- Want the lowest cost? NOW Magnesium Citrate: $0.24 per 300 mg at list price. Each tablet has 200 mg; take 1, because the 2-tablet serving (400 mg) is over the limit. Not on a testing list.
- Want a powder? Natural Vitality Calm, now sold as MaxCalm (citrate plus glycinate): 350 mg in 2 teaspoons, $0.27 per 300 mg. Not on a testing list.
All magnesium citrate supplements compared
The 3 citrates we score, ranked by what 300 mg of magnesium costs at each brand’s own list price, cheapest first.
| Product and size | Per 300 mg | A serving | A year |
|---|---|---|---|
| 1 NOW Magnesium Citrate 200 mg 250-tablet bottle, list $39.99, 400 mg magnesium in 2 tabletsNo testing list found · score 7.0/10 | $0.24 | $0.32 | $117 |
| 2 Natural Vitality Calm Magnesium Citrate Powder 16 oz tub, list $35.79, 350 mg magnesium in 2 tsp (4 g) powder in waterNo testing list found · score 7.0/10 | $0.27 | $0.32 | $116 |
| 3 Nature Made Magnesium Citrate 250 mgTop pick 120-count bottle, list $23.59, 250 mg magnesium in 2 softgelsUSP Verified · score 9.0/10 | $0.47 | $0.39 | $144 |
The score (out of 10) weighs testing, dose, cost, the label and recalls; it compares citrates with each other only. That is why the most expensive citrate per mg has the top score: it is the only one on a testing list. Amazon’s price can differ from these list prices.
Does one serving stay under the 350 mg limit?
Only one of the three does. Here is what each label’s serving gives and what to take instead:
| Product | Label serving | Vs the limit | Take instead |
|---|---|---|---|
| NOW Magnesium Citrate 200 mg | 400 mg | Over the limit | 1 tablet (200 mg) |
| Natural Vitality Calm Magnesium Citrate Powder | 350 mg | The whole limit | about 1½ teaspoons (about 260 mg) |
| Nature Made Magnesium Citrate 250 mg | 250 mg | Under the limit | 2 softgels (250 mg) |
Count every product you take, including a multivitamin. A dose of 200 to 300 mg from a supplement fills the typical food gap and leaves room for error. How much magnesium per day, by age.
How to read a magnesium citrate label
- The magnesium line is what counts. The “Magnesium” line on the Supplement Facts panel is the magnesium itself (the elemental amount), not the weight of the whole compound (NIH).
- The words in brackets name the form. “(as magnesium citrate)” means citrate only. If oxide is named too, part of it is the poorly absorbed form.
- Check the serving size. A serving can be 1, 2 or 3 pills. NOW’s 400 mg is for 2 tablets.
- Softgels carry a little oil. Nature Made’s 2 softgels add 15 calories and 1 g of fat.
What is magnesium citrate?
Magnesium bound to citric acid, the acid in citrus fruit. About 16% of the compound’s weight is magnesium. It dissolves well in water, which is one reason it absorbs better than oxide: small studies found citrate, aspartate, lactate and chloride better absorbed than oxide and sulfate (NIH). It is the most common form on the shelf: of the 833 magnesium labels we read in NIH’s database, 351 name citrate, more than any other form (oxide is next, on 244). A label is counted once for each form of magnesium its Supplement Facts panel names, so a label with two forms counts under both. Citrate or glycinate? Neither is proven better; glycinate vs citrate compares them by goal.
Do not confuse the pills with the bottled drink. Magnesium citrate oral solution is a laxative, taken for occasional constipation or before a colonoscopy, and should not be used for more than a week without a doctor (MedlinePlus). The softgels and tablets here are daily supplements at a much lower dose.
If you have kidney disease, ask your doctor before you take magnesium. Weak kidneys cannot clear the extra, so it can build up (NIH). Antibiotics: take tetracyclines (such as doxycycline) or quinolones (such as ciprofloxacin) at least 2 hours before or 4 to 6 hours after magnesium (NIH).
Every size, ranked by cost per 300 mg
All 7 sizes the brands sell
| Product | Size | List price | Per 300 mg |
|---|---|---|---|
| NOW Magnesium Citrate 200 mg | 250 Tablets (linked) | $39.99 | $0.24 |
| Natural Vitality Calm Magnesium Citrate Powder | 16 oz (453 g) Powder (linked) | $35.79 | $0.27 |
| NOW Magnesium Citrate 200 mg | 100 Tablets | $19.99 | $0.30 |
| Natural Vitality Calm Magnesium Citrate Powder | 8 oz (226 g) Powder | $22.49 | $0.34 |
| Nature Made Magnesium Citrate 250 mg | 120 Count (linked) | $23.59 | $0.47 |
| Nature Made Magnesium Citrate 250 mg | 60 Count | $14.19 | $0.57 |
| Natural Vitality Calm Magnesium Citrate Powder | 30 Stick Packs (255 mg a packet) | $20.82 | $0.82 |
How these 3 magnesium citrate products were ranked
By cost per 300 mg of magnesium at each brand’s own list price: the price of the bottle our link opens, divided by its servings and the magnesium in each. We quote no Amazon prices. We searched each product on five public testing lists on October 14, 2026; only Nature Made’s softgels are on one (USP Verified). We pick from products on a testing list, which is why our top pick is not the cheapest. Commission does not enter it; the rate is the same whichever citrate you buy.
Questions
What is the best magnesium citrate supplement?
Nature Made Magnesium Citrate: 250 mg of magnesium in 2 softgels, on USP Verified, $0.39 a day at list price. It has the top score of the citrates we score. NOW costs less per mg at list price but is on no testing list, and its 2-tablet serving is over the daily limit.
What is magnesium citrate good for?
Raising your magnesium intake, with better absorption than oxide (NIH). It can also loosen stools, which helps some people and bothers others. Magnesium citrate drinks are a separate product: a laxative for short-term use (MedlinePlus).
How much magnesium citrate should I take?
Count the magnesium line, not the softgels. Adults need 310 to 420 mg a day from food and supplements together; from supplements, stay at or under 350 mg (NIH). One Nature Made serving (250 mg) fits; one NOW serving (400 mg) does not, so take 1 NOW tablet. How much magnesium per day.
Is NOW magnesium citrate third-party tested?
We found no listing for it on NSF/ANSI 173, NSF Certified for Sport, USP Verified, Informed Choice or Informed Sport (searched October 14, 2026); we found no NOW magnesium on NSF’s lists. That does not mean the label is wrong; no outside program confirms it. Nature Made citrate is on USP Verified.
Is Natural Vitality Calm still magnesium citrate?
Partly. Natural Vitality’s page says the original unflavored Calm tub is now sold as MaxCalm. Its label gives 350 mg of magnesium per 2 teaspoons as citrate and glycinate together. That is the whole daily limit, so use a little less. The stick packs hold 255 mg each.
Does magnesium citrate cause diarrhea?
It can, at higher doses. Too much magnesium from pills most often causes diarrhea, sometimes with nausea and stomach cramps. That is why the limit is set where it is (NIH). If it does, take it with food, split the dose or switch to glycinate. Magnesium side effects.
Is magnesium citrate better than oxide?
For raising your magnesium, yes: oxide was only about 4% absorbed in one study (Firoz 2001). For constipation, oxide has the trials. Citrate vs oxide.
More on magnesium citrate
- Glycinate vs citrate · citrate vs oxide · all forms compared
- Best magnesium overall · what every glycinate costs · gummies
- Dosage guide · best time to take it · side effects · magnesium guide
Look up a magnesium citrate label
Want to check a product that is not on this page? Search our supplement label lookup for the label facts filed for it with NIH.
Sources
- Prices: each brand’s own list price (its regular one-time price) for every size it sells, checked October 14, 2026. We quote no Amazon prices; Amazon is only where the buy links go.
- Labels: Nature Made’s Supplement Facts panel (shown above); NOW’s page (200 mg a tablet, serving 2 tablets); Natural Vitality’s MaxCalm label (350 mg per 2 teaspoons, citrate and glycinate; stick packs 255 mg), read October 14, 2026.
- Testing lists: NSF/ANSI 173, NSF Certified for Sport, USP Verified, Informed Choice and Informed Sport, searched October 14, 2026.
- NIH Office of Dietary Supplements. Magnesium fact sheet for health professionals (updated January 6, 2026).
- MedlinePlus. Magnesium citrate (saline laxative).
- Firoz M, Graber M. Bioavailability of US commercial magnesium preparations. Magnes Res. 2001. PubMed 11794633
This page is for information. It is not medical advice.