How Much Water Does a Child Need? Hydration Guidance by Age
Source: NHS, CDC, European Food Safety Authority (EFSA), WHO | Last reviewed: April 2026
Most parents know that children should drink enough water — but knowing the right amount, and how to practically achieve it, is less straightforward. This guide provides age-appropriate hydration guidance and practical tips, based on NHS, CDC, and European Food Safety Authority (EFSA) recommendations.
Daily Fluid Intake — Reference Table by Age
The amounts below refer to total fluid intake from all sources — water, milk, other drinks, and water naturally present in food (which accounts for roughly 20% of total intake in most diets).
| Age Group | Recommended Total Fluid/Day | Notes |
|---|---|---|
| 0–6 months (breastfed) | Breastmilk only | No additional water needed |
| 0–6 months (formula-fed) | Formula provides fluids | Water only with medical guidance |
| 6–12 months | Small amounts of water with meals | Breastmilk or formula remains main drink |
| 1–3 years | ~1.3 litres (about 5–6 cups) | Water and milk are best |
| 4–8 years | ~1.2–1.6 litres | Plain water throughout the day |
| 9–13 years | ~1.6–2.1 litres | Boys slightly more than girls |
| 14–18 years | ~1.8–2.6 litres | Increases with activity |
Source: EFSA Dietary Reference Values; NHS eatwell guidance
Important caveat: These are reference ranges, not targets to hit precisely. Individual needs vary based on climate, activity level, diet content, and health status.
The Best Drinks for Children by Age
Babies (0–12 months)
- Breast milk or formula is sufficient for all fluid needs in the first 6 months
- From around 6 months, small amounts of cooled boiled water can be offered with meals
- No cow's milk as a main drink before 12 months (small amounts in food are fine)
- No fruit juice, squash, or sweetened drinks
Toddlers (1–3 years)
- Plain water is the best drink
- Full-fat cow's milk up to about 400ml/day is appropriate (semi-skimmed from age 2)
- No more than 150ml of diluted unsweetened fruit juice at mealtimes — not as a regular drink
- No fizzy drinks, squash, or flavoured water with added sugar
Children (4–11 years)
- Plain water should be the main drink throughout the day
- Milk is a good source of calcium and fluid — semi-skimmed is suitable
- Limit juice to 150ml at mealtimes; avoid sweet drinks and flavoured waters
- Sparkling water is fine, but acidic drinks consumed too frequently can affect tooth enamel
Teenagers (12–18 years)
- Water remains the best main drink
- Energy drinks, sports drinks, and high-caffeine drinks are not recommended for under-18s
- NHS guidance advises keeping caffeine (from tea, coffee, cola) to a maximum — under-18s should limit caffeine intake
How to Tell If a Child Is Getting Enough Fluid
The most practical check is urine colour:
| Urine Colour | Hydration Status |
|---|---|
| Pale yellow (like lemonade) | Well hydrated |
| Dark yellow or amber | Mildly dehydrated — drink more water |
| Brown or very dark | Significantly dehydrated — seek medical advice |
| Colourless | May be drinking too much (rare in children) |
Other indicators of good hydration: regular wet nappies (infants), frequent urination in older children, moist lips and mouth, normal energy levels.
Signs of Dehydration in Children
Mild to moderate dehydration:
- Darker urine
- Fewer wet nappies than usual (infants)
- Dry lips and mouth
- Irritability
- Fatigue and reduced energy
Severe dehydration — contact a doctor:
- Sunken fontanelle (soft spot) in infants
- No tears when crying
- Sunken eyes
- Very infrequent urination (less than once every 8 hours in children over 1 year)
- Extreme lethargy or difficulty waking
Dehydration in infants and young children can worsen quickly. If a young child has diarrhoea and vomiting and is not keeping fluids down, contact your doctor or NHS 111.
Practical Tips for Getting Children to Drink More Water
- Keep water visible and accessible — a water bottle at their seat, on their desk, or in their bag removes the barrier of having to ask
- Infuse plain water — add a slice of lemon, cucumber, or strawberry if a child finds water boring
- Offer water with every meal — it becomes routine quickly
- Use a fun cup or bottle — for younger children, the vessel often matters as much as the drink
- Lead by example — children notice what adults drink and follow suit
- Increase intake during hot weather and sport — physical activity in summer significantly increases fluid needs
What to Avoid
| Drink | Why to Limit or Avoid |
|---|---|
| Fruit juice | High natural sugar; 150ml/day max, at mealtimes, diluted |
| Squash / cordial | Contains sugar or sweeteners; regular use damages teeth |
| Fizzy drinks | High sugar; acidic; no nutritional value |
| Sports drinks | High sugar and electrolytes; not for everyday use |
| Energy drinks | Caffeine; not suitable for under-18s |
| Flavoured milk drinks | High sugar; occasional treat only |
Hydration and Child Nutrition
Hydration is one of several interconnected nutrition factors for children. Adequate fluid intake supports digestion, cognitive focus, physical activity, and kidney function. It also helps children distinguish genuine hunger from thirst — a common cause of overeating.
Use our Child Nutrition Calculator for estimated daily calorie and hydration guidance based on your child's age, sex, and activity level.
Related Guides
- Child Nutrition Calculator — daily calorie and hydration estimates
- How Many Calories Does a Child Need by Age? — calorie guidance by age band
- Balanced Diet Basics for Children — food group guidance
- When to Seek Professional Nutrition Advice — when a dietitian can help
This guide is for general information only. Reference values are from NHS, CDC, and EFSA guidance. Specific medical conditions may alter fluid requirements. Always consult your child's GP or healthcare provider for personalised advice.