Powdered Infant Formula: How to Prepare and Store

Powdered infant formula is the least expensive type of formula.  Since it is not a sterile product, extra care must be taken when using it.  Powdered infant formula is not recommended (unless prescribed) for babies who:

  • were born premature (<37 weeks old) and are under two months of age
  • were born with a low birth weight (<2500g) and are under two months of age
  • have a weakened immune system

If you are unsure, talk to your health care provider before giving powdered formula to your baby.

 Getting started

Preparing powdered infant formula

  • Always follow the manufacturer’s directions on the label.
  • Mix the right amount of water with the formula.  Adding extra water to make it thinner or less water to make it thicker is dangerous for your baby.
  • Never mix any other kind of food, drink or type of formula in your baby’s bottle. Adding cereal to your baby’s bottle won’t help him sleep and can cause choking.
If you are preparing a bottle to use right away
  •  You can mix cooled sterile water with the powder just before feeding your baby.  Using it right away doesn’t give bacteria time to grow.
If you are preparing bottles to be used later on
  • Mix the formula powder with sterile water that is at or above 70°C to kill any bacteria (see image below). A digital thermometer will help you check the temperature.
  • Rapidly cool the prepared bottle by placing it in a bowl of ice water. Once it has cooled, store the prepared bottle in the refrigerator
  • how to prepare powdered formula

    Updated and reproduced with permission from the Manitoba Government

Storing and Using

  • Do not use prepared formula if it has been unrefrigerated for more than two hours.
  • Use any unused prepared bottles within 24 hours.
  • Your baby should start a new bottle at each feeding. After each feeding begins, use the bottle of formula within two hours or discard.
  • Throw away any formula your baby doesn’t finish. Never reuse, reheat or put it in the fridge for later use.
  • If you are going out and need to take formula with you:
    • Bring a sterilized bottle with the right amount of powder in it for one feeding
    • Bring cooled sterilized water in a separate container
    • Just before you feed your baby, pour the right amount of sterilized water into the bottle with the powder
    • Mix well and feed
  • An opened container of powdered formula can be kept covered in a cool dark place for no more than 30 days.

Warming the bottle before feeding

  • Most babies like to drink their formula at room temperature.
  • You can warm the bottle by placing it in a bowl of warm water.
  • Never warm bottles in a microwave oven as it causes hot spots and can burn your baby’s mouth.
  • Check the temperature of the formula by placing some drops on the inside of your wrist.