Vitamin D3 + Magnesium
What taking vitamin d3 and magnesium together costs, ranked by real cost per dose. A value comparison — not medical advice.
Why people take them together
Magnesium is one of the cofactors the body uses to activate vitamin D, so the two are commonly paired. We compare the cost of the pairing, not whether you should combine them — supplements can interact with each other and with medications, so confirm any stack with your clinician or pharmacist first.
Frequently asked
How much does taking Vitamin D3 and Magnesium together cost per day?+
About $0.07 a day at the cheapest we track — $0.03 for vitamin d3 plus $0.05 for magnesium, each the lowest cost-per-dose option in our Amazon US catalog as of July 2026. That's roughly $2.21 a month.
Can you take Vitamin D3 and Magnesium together?+
Many people do — Magnesium is one of the cofactors the body uses to activate vitamin D, so the two are commonly paired. This page compares the cost, not whether the combination is right for you: check with your clinician or pharmacist about interactions with your medications and conditions before combining supplements. Not medical advice.
Is it cheaper to buy Vitamin D3 and Magnesium separately or as a combo product?+
We rank single-ingredient products, so you can pick the cheapest per dose of each and add them up. Combo products can be more convenient, but they aren't always cheaper per dose — compare the combined single-ingredient figure above against any combo you're considering.