Pitcher Method | Safely Storing Breast Milk and Formula

Whether you breastfeed or formula-feed your baby, one of the most challenging parts of preparing milk is storing it.

The American Association of Pediatrics (AAP) has recently changed their guidelines to allow you to store milk in one place over the course of 24 hours.

What is the pitcher method? The pitcher method involves collecting pumped breast milk throughout one day in a closed pitcher and using it to prepare bottles for the next day. This method saves space in the refrigerator and resources over the course of time. You’ll also have fewer bottles to wash.

Read on to learn more about the benefits of the pitcher method.

Pitcher Method: Breast Milk

If you breastfeed or pump milk for your baby, the pitcher method can help you save time during pumping sessions and space in the refrigerator.

The pitcher method involves collecting all your pumped breast milk in one container and using the milk from the day to prepare bottles for the next day. You can also freeze any leftover milk you’ve expressed.

Can You Mix Breast Milk From Different Pumping Sessions?

You can mix breast milk from different pumping sessions throughout the day or week. It lasts in the refrigerator for four days and in the freezer for six months.

Cool the milk you just expressed to the same temperature as the milk already in the fridge before mixing so that it mixes well.

You’ll have to use or freeze the combined milk over the next few days. Avoid mixing breast milk from different pumping sessions if you have a high-risk or special needs baby.

Keeping the container clean is more challenging if you keep opening it and adding milk.

Can You Add Freshly Expressed Breast Milk to Refrigerated Milk?

Yes, you can add freshly expressed breast milk to refrigerated milk. Before mixing your freshly expressed breast milk with the milk in the refrigerator, you should lower the temperature of the expressed milk with ice packs or by putting it separately in the fridge.

Avoid mixing warm breast milk with frozen breast milk because it could partially thaw the frozen milk. Do not defrost the frozen breast milk until you’re ready to use it.

Can I Mix Morning and Evening Breast Milk?

Yes, you can mix morning and evening breast milk, especially if you have many pumping sessions throughout the day.

Make sure to cool the milk to the temperature of the milk you have in the refrigerator already before mixing. The milk will last up to four days in the fridge and 12 months in the freezer.

A new mom using an electric pump to extract milk.

What Do You Do With the Leftover Milk After Making Bottles?

You can freeze the leftover milk after making bottles. Milk stored in the refrigerator is only safe for babies to consume for up to four days.

Storing the extra milk in the freezer can increase the milk’s shelf life to 12 months. Remember that once you defrost the milk, you can’t freeze it again.

Pitcher Method: Formula

While you can make one batch of formula to prepare bottles when it’s convenient for you, experts recommend putting it in separate bottles instead of in one large pitcher.

Instead of struggling to mix formula into a bottle in the middle of the night, you can get the bottle ready in advance.

How Much Formula Can You Make in Advance?

You can make up to 24 hours’ worth of formula in advance for your baby. The exact amount depends on how much milk your baby consumes each feeding.

If you prepare it in advance, make separate bottles to prevent the spread of bacteria. Then, you should use each bottle within 24 hours.

How Long Can You Keep Formula Once Made Up?

According to the CDC, once you’ve made up the batch of formula, you can keep the bottle at room temperature for up to two hours.

Once your baby starts eating from the bottle, you can only keep it for one hour. The formula lasts in the fridge for 24 hours.

How Long Can I Keep Formula in the Fridge?

According to the CDC, you can keep formula in the fridge for up to 24 hours. Use separate bottles to prevent contaminating the whole batch whenever you feed your baby.

Once you’ve started feeding your baby a bottle, you can only keep the formula for an hour.

Is the Pitcher Method Safe?

Yes, the pitcher method is safe, but follow some safety precautions to help prevent the spread of bacteria:

  • Cool expressed milk to the same temperature as the refrigerator.
  • Use a food-grade container made of plastic or glass to store the milk.
  • Collect expressed milk over the course of one day.
  • Use milk within four days in the refrigerator or six months in the freezer.

AAP Breast Milk Storage Guidelines

Keep these breast milk storage guidelines in mind as you prepare your bottles for your baby:

  • Keep your containers clean by washing your hands and pumping directly into storage containers.
  • Freshly expressed breast milk should be used or frozen within four hours at room temperature or four days in the refrigerator.
  • Frozen breast milk is safe for up to 12 months.

AAP Formula Safety Guidelines

In light of the recent formula shortage, formula safety is more important than ever. Follow these guidelines for safely feeding your baby formula:

  • Keep your containers clean by washing your hands and pumping directly into storage containers.
  • Avoid watering down formula or making your own formula.
  • Store and prepare infant formula based on the manufacturer’s directions.
  • Always wash your hands before preparing and handling formula.
  • Wash bottles after every feeding.
  • Throw away formula your baby didn’t finish from a bottle after 2 hours.

Why Use the Pitcher Method

Use the pitcher method to save time and resources. One of the most challenging aspects of pumping or mixing formula is all the parts you have to clean.

The pitcher method allows you to cut down on the number of bottles to clean and help prepare future bottles more efficiently.

Pitcher Method Pros and Cons

The pitcher method may not be for everyone, but it can save you time and resources to streamline the process of preparing bottles for your baby.

Pitcher Method Benefits

You may want to use the pitcher method to prepare your bottles because of these benefits:

  • Simplify breast milk storage: Save a pitcher of milk and prepare bottles for the next few days with one batch.
  • Save space: If you use pitchers instead of bottles, you can use up less space in the refrigerator.
  • Freeze milk: You can freeze the breast milk you don’t use that day to have an extra stash in the freezer.

Drawbacks to the Pitcher Method

Keep in mind that the pitcher method might not be for you because of these drawbacks:

  • If you drop or break the container, you’ll lose all the milk you’ve stored at once.
  • It may be more challenging to sterilize the containers than a bottle, especially if the container doesn’t fit in the dishwasher.

Pitcher Method Containers

When choosing a pitcher container, pick one that holds more milk than you pump in a day. It should have a spout and a lid. Check out these pitcher-method containers.

Dr. Brown’s Mixing Pitcher

If you feed your baby formula, Dr. Brown’s Formula Mixing Pitcher has a blade that removes clumps from your batch and helps eliminate air bubbles in the formula.

You can make up to 32 ounces of formula for your baby to use for the next day. It’s dishwasher safe, and the parts are easy to disassemble.

Heavy Duty Glass Mason Jar Pitcher

A mason jar may not be specifically for formula or breast milk, but it’s sturdy and compact enough to save space in the refrigerator. A glass container is usually better for breast milk because the fat is less likely to stick to a glass jar.

Cleaning and Sanitizing Pitchers

Clean and sanitize any container you use according to the manufacturer’s instructions.

Washing the pitcher by hand with soap and warm water will often be safe for your baby, but if your baby has a medical condition that makes them sensitive to bacteria, you should sanitize the pitcher.

Labeling Pitchers

When labeling pitchers, always label based on the first or oldest batch of milk. Then, you should use the milk within four days of that date if stored in the refrigerator.

How To Start the Pitcher Method

Follow these tips to get started with the pitcher method:

  1. Get a food-grade glass or plastic container.
  2. Start pumping, and put your milk in the container.
  3. Label the container with the time and date of the first pumped milk.
  4. As you add milk throughout the day, mix it with a silicone spatula to incorporate the fat fully.
  5. After you use or freeze all the milk, sterilize the container in the dishwasher or with a sanitizing spray.


The pitcher method is an excellent way to store milk efficiently in the fridge, but it might not be for everyone. When handling milk in a pitcher, wash your hands and sterilize all the parts to keep your baby safe.