How Much Milk Should You Put in a Bottle for Your Breastfed Baby?
If you’re pumping and offering a bottle—whether it’s just occasionally or part of your daily routine—figuring out how much milk to put in can feel tricky. There’s no one perfect number, and when you’ve worked hard for every drop, the last thing you want is to waste it.
Let’s walk through what’s typical, what’s flexible, and how to confidently give your baby what they need.
There’s No One-Size-Fits-All Amount
Breastfed babies don’t take the exact same amount at every feeding. Bottle sizes can vary based on how often they eat during the day, how recently they last fed, and what kind of feeding mood they’re in. Just like us, sometimes they want a full meal and other times they’re good with a small snack.
That means there’s a range of what’s normal, and it’s okay if each bottle isn’t the exact same size.
A Simple Way to Estimate
If you want a place to start, here’s a helpful guideline:
Most babies take in about 24 to 30 ounces of breastmilk per day.
Divide that number by the number of feedings in 24 hours to get an average per bottle.
For example, if your baby eats 8 times a day:
24 oz ÷ 8 = about 3 ounces per bottle
If your baby is eating more frequently like 12x per day..
24oz ÷ 12 = about 2 ounces per bottle, etc. etc.
Some bottles may be smaller, some may be larger. That’s completely normal.
👇Here are some of my favorite bottles👇
Start Small to Avoid Milk Waste
In the early months when schedules are unpredictable, it’s often helpful to offer a smaller bottle first—maybe 2 to 3 ounces—and then warm up more if your baby still seems hungry. This can help reduce wasted milk while you’re still learning their patterns.
Pumped milk is valuable and takes time to collect—as you well know. Offering less at first gives you the option to add more without feeling like you’re pouring milk (and effort) down the drain.
What Happens As Your Baby Grows?
One of the most surprising things to many parents is that the amount of breastmilk a baby needs doesn’t continue to increase throughout the first year.
Your supply gradually builds in the early weeks, and then stabilizes. After that, your body keeps making what your baby needs, as long as there’s regular demand.
Even though your baby will grow quickly, the amount of milk they take often stays fairly steady after the first month or so. Instead of increasing volume, your milk actually adapts in composition to meet your baby’s changing needs.
Why Formula Bottles Often Look Bigger
You may notice that formula-fed babies often take larger and larger bottles over time. This is usually not because they need more calories. It’s often because they are not pace fed.
When bottles flow quickly and babies don’t get breaks, they may take in more milk before they realize they’re full. Over time, this can lead to bigger bottles becoming the norm—not because the baby needs more, but because of how they’re being fed.
All babies have roughly the same caloric needs to grow and develop well. Using paced bottle feeding with breastmilk helps your baby stay in tune with their natural hunger and fullness cues. You can read all about paced feeding here!
A Few Reminders
Some feeds will be smaller, some will be bigger. That’s expected.
Your baby’s bottle size will depend on how often they’re eating during the day.
8oz bottles are not the norm (at least they shouldn’t be).
It’s okay to start with less and add more if needed.
There’s no perfect number to chase. What matters most is that your baby is fed, growing well, and showing signs of satisfaction after feeding.
If you ever feel unsure or want help figuring out what’s right for your baby’s routine, we’re here. Whether it’s setting up a bottle plan, learning paced feeding, or just getting some peace of mind, you don’t have to figure it all out on your own.
