Free shipping on orders over $60!

Changing Formulas: A Guide to Switching Your Baby's Formula

Changing Formulas: A Guide to Switching Your Baby's Formula

Listen to this article:

There are many different reasons why you might need to switch to a different brand of baby formula. Maybe your current infant formula is too expensive, or you wish it had cleaner ingredients. Or maybe your baby’s sensitive digestion system isn’t agreeing with it very well. When switching brands, you might find yourself wondering whether or not it’s safe to do so.

Put simply, switching baby formulas or switching to a new baby formula brand is safe—as long as you do it in the right way. 

In this article, we’ll explain how to switch formulas safely in a few easy steps. For more information on how much formula to give when supplementing, check out our blog!

How to Switch Baby Formulas: A Step-By-Step Guide

If you want to switch baby formulas, just follow these five steps:

1. Speak With Your Pediatrician

Every baby has unique health concerns. Even though the internet can provide a wealth of helpful information, it’s always a good idea to consult with your baby’s doctor first. After all, you can never be too cautious with your little one’s well-being. 

2. Do Your Research

Once you’ve gotten the go-ahead from your pediatrician, you can start researching different brands of formulas. As you compare your options for baby formula, pay close attention to their:

  • Protein base – Cow’s milk, goat’s milk, and soy milk are three popular protein bases. However, if your baby’s stomach is sensitive to soy or dairy or you suspect lactose intolerance with milk formula, you may want to look for a formula with a different type of protein base, like almonds. This adjustment could be what your baby’s delicate tummy needs to enjoy more comfortable digestion. 
  • Nutritional content – By comparing nutritional information across brands, you can find out which formula offers the most vitamins and minerals, as well as the best balance of macronutrients.
  • Clean ingredients – Some baby formulas are processed more than others. If you care about feeding your baby clean ingredients, look for a brand that is GMO-free, low in sugar, and minimally-processed. 
  • Form – You can find formulas in powdered form, concentrated liquid form, and ready-to-use form. Powder and concentrated liquid formulas need to be mixed with water before you serve them to your baby. Of the three, powder formula is usually the most cost-effective option. 

Once you’ve found a new formula that checks all of the boxes, you can put it to the real test by letting your baby try the different formula out.

3. Choose A Formula Introduction Method

As you introduce your baby to a new formula, it’s a good idea to go slow and transition them gradually. This will give your baby’s sensitive tummy and taste buds some time to adjust to the new ingredients. 

The best time to introduce them to the new formula is in the morning. This way, if your baby has an allergic reaction or digestive issues, you’ll have plenty of time to notice and take action.

With that being said, here are two methods for gradually transitioning your baby to a new formula:

  • The Mix Method – Some babies don’t like the taste of new formula right away. To overcome this obstacle, you can serve them a mixture of the two formulas for a few  days. This will help them adjust to the new taste. 

To use this method, simply increase the ratio of the new formula each time you prepare your baby’s bottle. You can follow a formula schedule that looks something like this:

  • First day: 25% new formula, 75% old formula
  • Second day: 50% new formula, 50% old formula
  • Third day: 75% new formula, 25% old formula
  • Fourth day: 100% new formula

You can also prolong each of these steps for multiple days to give your baby an even slower transition. 

Note: Before you try this method, ask your pediatrician if the two formulas’ ingredients can safely be mixed together. If you're using a formula with a different protein base, you may want to avoid this method and try out the following one instead. 

  • The Bottle Method – Another way to slowly introduce a new formula is to give your baby one full bottle of the new formula each day and gradually increase the number, like this: 
  • First day: One bottle of new formula
  • Second day: Two bottles of new formula
  • Third day: Three bottles of new formula
  • Fourth day: Four bottles of new formula

During the rest of the day, let your baby enjoy their old formula. Continue increasing the number of new-formula bottles until it’s the only one you’re using. 

When to Switch Formula Cold Turkey

In most situations, gradually changing formulas is the best approach. However, there are some exceptions. For example, you may need to switch to a new formula right away if your baby’s current formula is causing:

  • Severe digestive issues
  • Allergic reactions
  • A medical condition

In these scenarios, you’ll want to quit the problematic formula cold turkey (with your pediatrician’s approval). While this sudden switch may lead to some digestive issues for your baby, they’ll typically subside in a few days.

What to Do If Your Baby Rejects the New Formula

Some babies will be picky about a new formula, even if you transition them onto it slowly. This is more common with babies who haven’t been introduced to any new tastes from solid foods yet. 

If your baby is having a hard time with the switch, you can encourage them to try the new formula by:

  • Introducing it when your baby isn’t too hungry or fussy – A super-hungry, fussy baby may be more inclined to reject the new formula if it’s not what they’re used to.
  • Feeding them when you're in a calm, relaxed mood – If you’re nervous about your baby’s reaction to the new formula, they may feel your energy and get nervous too. By relaxing beforehand, you can help your baby feel as if everything is okay. Playing soothing music can help you both relax during the process. 
  • Distracting your baby – Redirecting your baby’s attention away from the new taste can also ease the transition. Sing a soothing song to them or distract them with silly faces. 

These small steps can increase the likelihood that your baby will accept the new formula. However, if your baby still rejects the new formula after a few days of offering it to them, you may want to choose another brand that they like better.

4. Monitor Your Baby’s Digestion

As your baby gets used to the new formula, it’s important to pay close attention to their digestion and mood for a few days. 

Start by tracking your baby’s digestion and mood for a few days before the transition. This will give you a baseline of data to refer back to. Once you start transitioning your baby to the new formula, take notes about their:

  • Spit up frequency
  • Diaper change frequency
  • Gassiness
  • Constipation
  • Stool texture and color
  • Fussiness

What to Expect When Switching Formulas

Anytime you switch formulas, you can expect the following:

  • Increased gassiness – As your baby’s digestive system adjusts, it’s not uncommon for them to experience more gassiness. This should subside after a week or two. 
  • Stool changes – Since every type of formula contains slightly different ratios of protein and fats, switching formulas may cause your baby’s stools to change in color, frequency, and softness. This is to be expected. However, if your baby develops diarrhea, contact your pediatrician and let them know. 

While gassiness and stool changes are common with a new formula, it’s still a good idea to keep track of this information. If you notice any significant changes in your baby’s digestion or mood, let your doctor know about them right away. 

5. Watch Out for Allergic Reactions

While some digestive changes are expected, others may indicate a serious allergic reaction. Dairy-based and soy-based formulas are the most likely ones to cause food allergies

No matter what type of formula you switch to, you should watch out for the following allergy symptoms:

  • Skin rashes
  • Eczema
  • Hives
  • Extreme fussiness
  • Vomiting
  • Blood-tinged stools
  • Facial swelling
  • Wheezing
  • Lethargy
  • Loss of consciousness

Some of these symptoms are signs of an anaphylactic response, so you should seek immediate medical attention if they arise. 

Note: As you transition to a new formula, don’t introduce your baby to any new solid foods. This way, you’ll be able to know if the new formula caused the allergic reaction, if one occurs. 

Else: An Allergen-Free, Plant-Based Formula

As you can see, switching baby formulas is safe and easy if you take the right steps. Whether you want to use formula to supplement while breastfeeding or to wean your baby completely, Else can help, if your baby is over 1. 

At Else, we’ve created an allergen-free, plant-based toddler formula and upcoming baby formula that’s packed with nutrition. It’s the clean alternative many parents have been searching for. Rather than using cow’s milk or soy, our Plant-Based Complete Nutrition for Toddlers is made from almonds, buckwheat, and tapioca, which offer all of the vital nutrients your baby needs to grow and develop.

Compared to many other plant-based baby formulas, Else has less sugar and comes fortified with plenty of nourishing vitamins and minerals. It’s also minimally processed, ensuring that each ingredient maintains its nutritional value. 

By choosing Else, you’ll be giving your toddler nothing else but the very best. 

If you are wondering how to transition your baby from breastmilk to formula or wondering when to start supplementing with formulas, we are here to help! Check out our blog for more information!


Consumer Reports. Baby Formula Buying Guide.

BabyCenter. Is your baby allergic to formula? Anaphylaxis in Infants & Children.



The content and advice provided in this article is for informational purposes only and is not a substitute for medical diagnosis, treatment, advice for specific medical conditions. Always consult a pediatrician to understand the individual needs of your child. 

Subscribe for weekly updates