How to Make Baby Formula: 3 Easy Steps for Safe Preparation

Last Updated On: September 1, 2026

What You'll Learn Today

• Clean your hands, bottles, and workspace first.
• Use safe tap water or bottled water for mixing.
• Refer to the label for proper mixing instructions.
• For powder, serve within 2 hours at room temp or store in the fridge for up to 24 hours.
• Never dilute formula, microwave bottles, or use old mixed formula.

What Do You Need to Make Baby Formula?

So you want to learn how to make baby formula? Here’s what you’ll need to get started:

• Clean baby bottles, nipples, nipple rings, and bottle caps
• Formula scoop (comes inside the container)
• Safe drinking water (boiled or sterilized if needed or directed by your baby's doctor)
• A clean surface and your hands washed with soap and water

Step 1: Clean and Prepare Your Equipment

1. Wash your hands thoroughly. We want to avoid exposing babies, who have developing immune systems, to any unwanted germs.¹
2. Use clean bottles. Sterilization helps eliminate contaminants and bacteria, providing additional protection for your baby's developing immune system.³
3. Prepare a clean workspace. This keeps germs out of your baby's bottle from the start.

Step 2: Measure and Mix Formula Correctly

1. Add water first, then formula powder. Powders mix best when added on top of water that is room temperature or cooler (35 to 75 degrees Fahrenheit).
2. Use the exact scoop-to-water ratio. Always follow the instructions on the label for measuring and mixing the formula. Using packed or unpacked scoops can affect how much you're feeding your baby and the texture of the formula. For a packed scoop, fill with powder and then firmly press the top of the scoop with a clean spoon or against the inside of the container similar to the way that you measure brown sugar. Level the scoop, using the back of a clean table knife, if necessary. For an unpacked scoop, fill with powder and gently tap the side of the scoop on the inside of the container to remove any air pockets and level the powder with the back of a clean table knife.
3. Mix thoroughly. Make sure the cap is on tight, and shake well.

Step 3: Check Temperature and Serve Safely

1. Test the temperature before feeding. Formula can be served as cool as 35°F. If you warm the bottle in a pan of hot (not boiling) water or under warm running tap water, place a drop on the inside of your wrist to make sure it’s not too hot.
2. Cool formula if needed. If the prepared formula is too warm to feed right away, keep the bottle capped and cool it under running cool water or place it in an ice bath. Test the temperature before feeding to make sure it isn’t too hot.¹
3. Never microwave bottles. This can cause uneven heating, leading to potentially harmful hot spots that might burn your baby.² Such hot spots may not be noticeable when testing the formula on your wrist.

What Water Should You Use for Baby Formula?

You'll want to use room temperature or cooler (35 to 75 degrees Fahrenheit) water for baby formula. Typically, tap water is safe, and it doesn’t need to be filtered.² Your child's doctor can help you determine the correct water to mix with our products, and whether you need to sterilize the water. Here are a few more answers to questions you may have about water in formula:

• Can I use distilled water for formula? Certainly! This kind of water is free from contaminants and impurities.³
• What water to use for formula when there’s a water main break? In this case, you can use bottled water or boil your water.²
• Do you have to boil water for formula? Ask your baby's doctor about the need to use cooled, boiled water for mixing.

How Much Formula Should You Use Per Bottle?

Standard powdered formula uses 1 unpacked level scoop of powder for every 2 ounces (60 mL) of water.⁵ Here’s how many scoops of formula you’ll need for 2 ounces, 4 ounces, and other quantities of water:

How much formula to use all depends on the manufacturer’s instructions. Always use the exact measurements listed on the label.

Adding too much water can dilute the nutritional value of the formula. Too little water can dehydrate your baby and could cause harm to their kidneys.²

Adding water to the bottle first makes sure you get the perfect amount of ingredients every time.

How Should You Warm and Serve Baby Formula?

Many babies like body temperature formula.⁵ If your baby prefers warm formula, you can heat up the bottle under running warm water. Avoid overheating or using the microwave, as these can burn your baby, especially if they’re starting to hold their bottle on their own.

How Long Is Baby Formula Good for After Mixing

Ideally, you’ll want to use baby formula within two hours of mixing it.

Storage and Timing Guidelines

• How long is formula good for once mixed? Baby formula prepared from powder or concentrate, or an opened ready-to-use container, shouldn’t be kept at room temperature for longer than two hours.²
• How long is formula good for once used? If the bottle has been warmed or feeding has begun, discard the formula after one hour.² When formula that has been warmed and/or fed remains at room temperature for one hour, bacteria normally present in an infant's saliva will grow quickly in the nutrient-rich formula.
• How long does formula last in the fridge? Prepared powder formula can be stored in a covered, clean container on the top shelf of your refrigerator (at 35° to 40°) for up to 24 hours.² Do not freeze formula. Opened, ready-to-use formula can be stored in the refrigerator for up to 48 hours.

Safety Tips to Follow When Preparing Formula

Now that you know how to make a formula bottle, here are a few additional tips to make the process easier and safer:

• Never dilute formula or add extra water—it can change nutrient density.
• Always follow the label instructions on your specific formula.
• Use clean bottles, nipples, and surfaces every time.
• Discard any unused formula after feeding starts or time limits are hit.
• Check expiration dates, and keep formula sealed in a cool, dry spot.

Keeping Formula Prep Simple

Mixing formula right doesn't have to stress you out, especially when sleep is short. Enfamil Family Beginnings offers feeding schedules, storage tips, and support so you handle bottles like a pro.

References:

1. https://www.healthychildren.org/English/ages-stages/baby/formula-feeding/Pages/how-to-safely-prepare-formula-with-water.aspx↗
2. https://www.cdc.gov/infant-toddler-nutrition/formula-feeding/preparation-and-storage.html↗
3. https://www.cdc.gov/hygiene/faq/↗
4. https://rmccares.org/2024/10/03/can-infants-drink-distilled-water-the-best-water-for-formula-feeding/#:~:text=Many%20pediatricians%20recommend%20using%20distilled%20water%20for,of%20nutrients%20from%20the%20formula%20without%20interference↗
5. https://www.seattlechildrens.org/conditions/a-z/bottle-feeding-formula-questions/↗