If you’ve ever wondered, “My baby looks thirsty… can I give water?”—you’re not alone. Water feels like the most harmless thing in the world. But for young babies, timing and amount really matter.

Quick answer (featured snippet-friendly):

Most babies can start having small sips of water around 6 months, typically when solids begin. Babies under 6 months usually don’t need water—breast milk or formula provides the hydration they need.  

Why babies under 6 months usually shouldn’t drink water

Before 6 months, babies’ nutrition and hydration needs are designed to be met by breast milk and/or infant formula. Adding water too early can fill a tiny stomach and reduce the amount of milk/formula they take in (which is where calories and nutrients come from). Major pediatric guidance supports offering water only when babies are older and starting solids.  

Also, it’s important not to dilute formula with extra water. Formula should be prepared exactly as directed because changing the water-to-formula ratio can be unsafe. (If you ever have concerns about formula access, your pediatrician can help you find safe options and support.)  

When to introduce water: around 6 months

Once your baby is about 6 months old and starting complementary foods, you can begin offering water in small amounts. The AAP’s HealthyChildren guidance suggests that around 6 months, babies can be introduced to water and generally only need about 4–8 ounces per day until age 1 (because breast milk or formula remains their main liquid source).  

The CDC also notes that when your child is about 6 months old, you can start introducing foods and drinks other than breast milk and infant formula.  

How much water is “enough”?

For most 6–12 month olds:

• Offer a few sips with meals, not instead of milk/formula.
• Aim for a small daily total (AAP often cites 4–8 oz/day).  

Think of water at this stage as practice (learning to sip from a cup) and a little support for hydration—especially as solids increase.

Best way to offer water (and build good habits)

• Offer water in an open cup or free-flow cup during mealtimes. This supports oral skills and is better for teeth than constant sipping from bottles.  
• Keep it simple: plain water is the goal.

If you’re in the UK, NHS guidance adds that if a baby is younger than 6 months and water is ever advised for a specific reason, it should be boiled and cooled first—but most babies still won’t need it routinely.  

What to avoid: juice and sweet drinks

It’s tempting to offer juice—especially if you’re worried about constipation—but health guidance is clear: babies under 12 months should not have juice.  

Stick with breast milk/formula for primary hydration, and use water as small sips once solids begin.

Medical note: This article is for education and does not replace medical advice. If your baby has feeding issues, poor weight gain, vomiting, diarrhea, or you’re concerned about hydration, contact your pediatrician.