When can babies have cow's milk?

The key is separating two different things: cow's milk as a drink, and dairy as a food. They have very different timelines.

As a main drink: wait for 12 months

Cow's milk should not be your baby's main drink until after their first birthday. Until then, breast milk or formula is the right choice. The reasons are real: cow's milk is low in iron, and leaning on it too early is linked to iron-deficiency anemia. It is also higher in certain proteins and minerals than a young baby's kidneys handle well, and it can irritate an immature gut. It simply is not built to replace formula or breast milk in year one.

As a food: fine from around 6 months

This is where parents get tangled up. Dairy foods are fine from about 6 months: full-fat yogurt, cheese, and small amounts of cow's milk stirred into cooking (like oatmeal or a sauce). Milk is one of the big-9 allergens, so introduce dairy on its own the first time and watch for a reaction, then make it a regular part of a varied diet.

At 12 months: whole milk, in moderation

After the first birthday, whole (full-fat) cow's milk can become a normal drink. Stick with whole milk, not low-fat, from 12 months to age 2, because toddlers need the fat for brain development. You can switch to lower-fat milk after age 2 if you like.

Keep an eye on the amount: roughly 16 to 24 ounces a day is a good ceiling. Too much milk fills toddlers up, dampens their appetite for food, and can itself contribute to low iron.[1]

Making the switch: slow, and by cup

The move to cow's milk is gradual, not a hard cutoff on the first birthday. Swap one formula or breast-milk feed at a time for a cup of whole milk over a week or two, so your baby's tummy and taste have time to adjust.[1] Offer it in an open or straw cup rather than a bottle, which also makes this a natural moment to start moving off the bottle.

And if you are breastfeeding and want to keep going, you can. Cow's milk is a convenient source of calcium and vitamin D, not a requirement: a breastfed toddler eating a varied diet does not need it at all.[2] Nurse as long as you both like, and treat milk as one food among many rather than a box to check.

What about plant milks?

Plant-based milks (almond, oat, rice, and so on) are generally not suitable as a main drink in place of breast milk, formula, or, after age one, whole cow's milk, because most are low in the fat and protein young children need. Fortified soy milk is the closest nutritional match after 12 months. If your child cannot have cow's milk, talk to your pediatrician about the right alternative.

Sources

1. [1] CDC: Cow's Milk and Milk Alternatives (Infant and Toddler Nutrition). cdc.gov.
2. [2] CDC: Weaning from breastfeeding. cdc.gov.

Related reading

See when babies can have water, introducing allergens (milk is one), and foods to avoid before age 1.

Frequently asked questions

Last updated July 2026. Next review January 2027. How we write these: grounded in widely published pediatric guidance (the AAP, WHO, the NIAID 2017 allergen guidelines, and the LEAP study), and pending independent review by a pediatric professional. See our editorial and medical policy for how we research, source, and update these.

This is general information, not medical advice, and has not been individually reviewed for your baby. Always talk to your pediatrician about your baby's diet, introducing allergens, and any reaction. In an emergency, contact emergency services.

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