Infant Formula Preparation and Storage

Carefully read and follow the instructions on the infant formula container. These steps will help you know how to prepare and store your infant’s formula correctly. Preparing your infant’s formula according to the instructions is important.

Here are additional pointers to keep in mind when preparing and storing your infant’s formula.

Download and print a handout on how to prepare and store powdered infant formula, available in English and Spanish.

Preparation

• Wash your hands well before preparing bottles or feeding your baby. Clean and sanitize the workspace where you will be preparing the infant formula.
  

  Download and print a handout on how to prepare and store powdered infant formula, available in English and Spanish.

• Bottles need to be clean and sanitized. To learn more about how to properly clean your baby’s bottles and other feeding supplies, visit the CDC webpage How to Clean, Sanitize, and Store Infant Feeding Items.
• Baby’s milk or infant formula does not need to be warmed before feeding, but some people like to warm their baby’s bottle.
  • If you do decide to warm the bottle, never use a microwave. Microwaves heat milk and food unevenly, resulting in “hot spots” that can burn your baby’s mouth and throat.
  • To warm a bottle: Place the bottle under running warm water, taking care to keep the water from getting into the bottle or on the nipple.  Put a couple drops of infant formula on the back of your hand to see if it is too hot.
• If you use powdered infant formula:
  • Use water from a safe source to mix your infant formula. If you are not sure if your tap water is safe to use for preparing infant formula, contact your local health department.
  • Use the amount of water listed on the instructions of the infant formula container. Always measure the water first and then add the powder.
    • Too much water may not meet the nutritional needs of your baby.
    • Too little water may cause your baby’s kidneys and digestive system to work too hard and may cause your baby to become dehydrated.
  • If your baby is very young (younger than 2 months old), was born prematurely, or has a weakened immune system, you may want to take extra precautions in preparing your infant’s formula to protect against Cronobacter (see box).
    Did You Know?

    Cronobacter can be caused by germs in infant formula.

    Cronobacter is a rare but serious infection that can be caused by germs in powdered infant formula. In most cases, it is safe to mix powdered infant formula following manufacturer’s instructions. But if your baby is very young (younger than 2 months old), was born prematurely, or has a weakened immune system, you may want to take extra precautions to protect against Cronobacter.

    Learn more about how to safely prepare your infant’s formula to prevent Cronobacter.
    Download a step-by-step handout [PDF-2.13MB]. 

Use Quickly or Store Safely

• Prepared infant formula can spoil if it is left out at room temperature.
  • Use prepared infant formula within 2 hours of preparation and within one hour from when feeding begins.
  • If you do not start to use the prepared infant formula within 2 hours, immediately store the bottle in the fridge and use it within 24 hours.
• Throw out any infant formula that is left in the bottle after feeding your baby. The combination of infant formula and your baby’s saliva can cause bacteria to grow. Be sure to clean and sanitize the bottle before its next use.
• Store unopened infant formula containers in a cool, dry, indoor place—not in vehicles, garages, or outdoors.
• Once a container of infant formula is opened, store in a cool, dry place with the lid tightly closed. Do not store it in the refrigerator.
• Most infant formulas need to be used within 1 month of opening the container (check the label).  When you first open the container, write the date on the lid to help you remember.
• Never use formula after the “Use By” date on the container.

Why are there different recommendations for preparing my baby’s powdered infant formula?

When preparing your baby’s powdered infant formula, it is important to know that recommendations can differ based on several factors including your baby’s age and the safety of the water.

How do I know which recommendations to follow?

There are different ways to safely prepare your baby’s powdered infant formula. See the guidance below to help you decide which is the safest option for your baby.

Most of the time, it’s safe to prepare powdered infant formula by mixing it with tap water (filtered or unfiltered) and following the manufacturer’s instructions on the container.

• Learn step-by-step instructions on how to prepare and store powdered infant formula. [PDF-4.8MB]

Take extra steps to protect your baby from germs that could possibly make them sick if:

Your baby is younger than 2 months old, born prematurely, or has a weakened immune system.

• Babies who are younger than 2 months old, born prematurely (before 37 weeks of pregnancy), or have a weakened immune system could get very sick if they drink formula that is contaminated with bacteria, such as Cronobacter. These bacteria can live in the environment or in dry foods like powdered infant formula. Cronobacter infections are rare but serious in infants.
• To kill germs like Cronobacter in powdered infant formula, the formula must be mixed with very hot water. Boil the water and then wait about 5 minutes before mixing with powdered infant formula. After mixing, the formula will be too hot to feed your baby, so it’s important to wait for the formula to cool first so you don’t burn your baby’s mouth.
• Learn about how you can protect your baby from Cronobacter infection when preparing powdered infant formula [PDF-2.1MB].

Take extra steps to protect your baby from germs that could possibly make them sick if:

There is an emergency and your water might not be safe to mix with powdered infant formula.*

• When there is an emergency such as a water main break, hurricane, or flood, your tap water for mixing your baby’s powdered infant formula may not be available or safe to use.
• If you believe the tap water is unsafe, use bottled water to prepare formula until local authorities say the tap water is safe to drink. If tap water is your only option you can make tap water safe by boiling or disinfecting it [PDF-714KB]. If you choose to boil your water, let the water cool to room temperature before mixing it with powdered infant formula. Always test the temperature before feeding your baby by putting a few drops of formula on your wrist so you do not burn your baby’s mouth.
• CDC provides step-by-step instructions on how to prepare and store powdered infant formula during emergencies [PDF-639KB] and how to clean infant feeding items (like bottles and nipples) during emergencies [PDF-953KB].

*If there is an emergency AND your baby is younger than 2 months old, born prematurely, or has a weakened immune system, follow the instructions above for preventing Cronobacter.