If you always have a water bottle nearby, it’s natural to wonder when your baby can start drinking water too. Babies need hydration, but for the first several months, breast milk or formula gives them everything they need.
Newborns and young infants should not drink plain water unless your pediatrician specifically tells you to. Too much water can fill their tiny stomachs, interfere with nutrition, and even affect their electrolyte balance.1,2
So, when can babies have water? Most babies can start having small sips around 6 months, usually when they begin solids. Here’s what to know about how much water is safe, how to introduce it, and which drinks to avoid.
Key Takeaways
- Newborns and young infants should drink only breast milk or formula unless their pediatrician says otherwise.1
- Babies can usually start having small sips of water around 6 months.6
- From 6 to 12 months, babies can have up to 4 to 8 ounces of water per day.6
- Too much water in young babies can interfere with nutrition and may cause water intoxication.1,2
- Avoid juice before age 1, and ask your pediatrician before introducing cow’s milk at 12 months.6
Can Babies Drink Water?
Not before 6 months, unless your pediatrician tells you otherwise. Before then, babies should get hydration from breast milk or formula.
It may come as a surprise that young babies shouldn’t drink any water at all! Newborns should drink only breast milk or formula, not water. These milks provide the only hydration babies need, and any beverages other than breast milk or formula at this age can actually be harmful.1
Of course, there’s nothing inherently toxic in water. You can even use tap water to mix baby formula, but you should boil it first and then cool it for babies under 2 months old.3
Related: Baby Milestones Month by Month
Why Can’t Babies Have Water?
Breast milk and infant formula are perfectly formulated to give your baby the right balance of water, electrolytes, and calories. This helps them maintain the perfect hydration status and allows them to grow from the calories in their milk.1
Plain water offsets the hydration and nutrition balance in milk, potentially causing two main issues:
1. Malnutrition
Babies have very small stomachs that are about the size of an egg.1 When babies have water, their little bellies may fill up on this calorie-free liquid instead of breast milk or formula. Then they aren’t hungry for milk, potentially leading to low blood sugar and poor weight gain.2
2. Water Intoxication
In addition to small stomachs, babies have very immature kidneys. Kidneys are organs that filter our blood, maintain proper hydration, and keep our electrolytes balanced. When a baby consumes water, the kidneys may be unable to keep up with peeing it out. If too much water remains in the blood, it dilutes the salt in the blood. An imbalance in blood salt levels due to excess water can cause seizures and brain damage.1
Other potential negative effects of infants drinking water include:2
- Impaired bonding
- Decreased breastfeeding duration
- Negative immune system effects
- Increased incidence of physiological jaundice
Related: How Much Weight Loss Is Normal for a Newborn
What To Do if You’re Worried About Dehydration
Babies are very good at responding to their own hunger and thirst cues. They’ll eat and drink when they’re hungry and stop when they’re satisfied.4 It can’t hurt to offer your baby more milk if you’ve been in the heat and think they could use more fluids than usual. Breast milk contains about 87% water, and formula contains about 85% water, so these milks provide all the hydration and nutrition they need.1
Symptoms of dehydration in babies include:5
- Not producing tears when crying
- Having a sunken soft spot on top of their head
- Having a dry mouth
- A decreased number of wet diapers
If you suspect your baby is mildly dehydrated, offer them their normal breast milk or formula.5 If your baby has signs of severe dehydration, such as irritability, fatigue, or poor feeding, contact your pediatrician immediately. Depending on your baby’s age, they may advise continuing breastmilk or formula or using an oral rehydration solution, such as Pedialyte. But they’ll likely want to see your baby or have you take them to the emergency department to assess whether they need intravenous fluids.5
Related: What to Know About Dehydration in Babies
When Can Babies Have Water?
Babies can start having sips of water around 6 months of age. At this point, water is unlikely to replace much of their hydration. The purpose of introducing water at this age is to familiarize babies with drinking from different types of cups and get them accustomed to the taste.6
From 6-12 months, babies can have up to 4 to 8 ounces of water per day. Water needs gradually increase after the first birthday, but the exact amount depends on age, diet, activity level, and your pediatrician’s guidance.6
How To Introduce Water to Your Baby
Once your baby hits that six-month mark and you’re ready to introduce them to some water, here are some considerations:
1. Cup Choice
When offering water to your baby, you can use a straw cup, sippy cup, or open cup:6
Straw cup
I like the Munchkin weighted straw cups for their soft silicone straws. Others recommend the Honey Bear water cup to teach a baby how to use a straw. However, there’s no need to purchase fancy products if they don’t fit your budget! Most grocery stores sell disposable straw cups that you can wash and reuse for the short time your children need them. Straw cups are an excellent choice because they’re healthier for your child’s teeth with long-term use.
Sippy cup
Some speech and occupational therapists advise against a regular sippy cup due to tongue positioning, swallow pattern, and speech and tooth development.7 However, the American Academy of Pediatrics still lists them as a transitional tool until your child can confidently drink from an open cup around age 2.8
Open cup
Learning to drink from an open cup is a valuable skill that can start in infancy.6 You may have to help baby at first, and there will be some spills, but I was surprised at how quickly my kids learned to use an open cup.
Related: 5 Tips on Weaning Baby From Bottle to Sippy Cup
2. How Much Water To Give
Once you’ve chosen a cup for your baby, you need to know how much water to put in it. You can offer small volumes of water throughout the day for babies aged 6-12 months.1 The total volume of water for this age range can be as much as 4-8 ounces per day, but this can be spread throughout the day.6
3. When To Give Them Water
Although these small volumes of water are unlikely to displace the milk your baby consumes at this age, it may be best to offer your baby water with meals, as they’re likely to have started some solid foods around the same time.1 I always used drinking from a straw cup as a fun “activity” when my babies were over 6 months old. If you want to offer baby a few sips of water or have them practice drinking from a straw at other points throughout the day, the volume is so small that it shouldn’t make a difference.
Related: How to Introduce Solids to Your Baby
When Can Babies Have Juice?
Many parents wonder about juice once their baby starts drinking water, but it is best to wait a little longer.
Once you’ve successfully found a cup for your baby and taught them how to drink water, you might be eager to introduce other beverages. However, you should avoid juice before age 1 because it provides sugar without any fiber.
Once children get accustomed to drinking sweet-tasting juice, getting them to drink plain water can be difficult. Feeding whole fruit is preferable to serving juice, even if it’s 100% fruit juice.6 Some parents choose to dilute fruit juice with water to reduce the sweetness.
At age 2, parents may decide to introduce small amounts of juice. The American Academy of Pediatrics recommends no more than 4 ounces per day for children ages 2 to 3 and no more than 6 ounces per day for children ages 4 and up.6
When Can Babies Have Milk?
Cow’s milk is another beverage parents often ask about, but timing matters here too.
Parents who feed their babies formula will be happy to know they can introduce cow’s milk at 12 months of age.6 Talk to your pediatrician about how to wean your baby off formula and introduce plain cow’s milk.
Introducing water is a small but exciting milestone. For the first 6 months, breast milk or formula provides the hydration your baby needs. Around 6 months, you can usually begin offering small sips of water with meals as your baby starts solids.
If you are worried about dehydration, your baby is not feeding well, or you are unsure how much water is safe, check with your pediatrician. They can help you decide what is best for your baby’s age, health, and feeding needs.
