Breastfeeding Bra Size Chart – find your nursing bra size

Approximately 80 percent of women wear the wrong bra size. This affects milk supply as too small bras block the milk ducts thus reducing the amount of milk supply. The blockage may also cause infections such as mastitis. A perfect breastfeeding bra size or a nursing bra size is essential in your online search.

Breastfeeding can be quite uncomfortable if nursing moms are not well informed on the best nursing apparel. You can use this helpful breastfeeding bra chart will help you a great deal during your breastfeeding journey

Breastfeeding Bra Size Table of content

Looking for Maternity Breastfeeding bra size charts, or Maternity leggingstanktopscheck it here.

When Should a Mother Start Preparing for Breastfeeding?

The journey towards breastfeeding begins from the pregnancy stage as many changes occur to the breasts during pregnancy. Did you know, for example,  that breast size doubles or even triples after childbirth then slowly returns to normal size after several months of breastfeeding? This happens as the milk ducts expand to create space for breast milk.

Please pay attention as we guide you on why a breastfeeding bra chart is important in your conception and motherhood journey.

Breastfeeding Bra sizing Chart: Why Is It important?

A breastfeeding bra size chart or Nursing Bra size chart is a guide that helps nursing mums to be able to determine the right bra size for them, ensuring more comfort during breastfeeding.

When shopping for a perfect bra, it is recommended to use a breastfeeding chart as your milk glands continue growing depending on the stages of nursing.

Here are the main benefits of utilizing a breastfeeding bra chart;

  • It will help you to determine the correct size of bra according to your breast size
  • You will purchase a breastfeeding bra that offers optimal comfort when wearing it
  • You will be able to choose a well-fitting bra easily from a wide range of nursing bras 
  • You will be able to learn about different types of nursing bras and their specific uses e.g nursing sports bra for workouts during lactation, sleep bra for bedtime, seamless nursing bra for wearing with light garments, wireless nursing bra, and underwire nursing bra that gives full support for heavy breasts.

How to take measurements for a fitting breastfeeding bra

Knowing your bust measurement prior to purchasing your breastfeeding bra is very important as you will get the correct size. There is nothing that can be as uncomfortable as wearing a small bra. It strains your rib cage and makes you so uneasy throughout the day. 

This is how to measure yourself correctly for a breastfeeding bra.

You will require the following:

  • A measuring tape
  • Piece of paper or booklet
  • Full-length mirror
  • A non-padded bra 
  • A pen

Follow these steps:

How to measure your bust size

1. With the tape measure still wrapped around you, adjust it so that it records your fullest bust measurement

2. Take the edge of the tape measure and place it on the side of your chest and hold both ends of the tape firmly in one hand. Make sure it is not too tight

3. Use the hand that is free to gently press the tape measure in between your breasts and onto your chest area

4. Again, note down the readings

How to measure your band size

1. Stand in an upright position

2. Wrap the tape measure around your back, just below the armpits (should be above your full breast tissue)

3. Check the floor, make sure the measuring tape is parallel to the floor for more accurate results

4. Exhale

5. Note down the measurements.

That is your rib band size. Keep the readings as we will use them later.

If the measurements appear in an odd number, try the bra size immediately above or below that one. For example: If you measured 31″, Then your band size should be 30″ or 32″.

Use this chart based on the band sizes, to determine your bra size;

Band Size
Bra Size
26-2866.04 – 71.1232
28-3071.12 – 76.2034
30-3276.20 – 81.2836
32-3481.28 – 86.3638
34-3686.36 – 91.4440

How to find the cup measurements (accurate cup size)

The correct cup measurement is key to a perfect bra fit. Here is how to arrive at the accurate cup sizes;

1. Bend over and ensure that your chest is parallel to the ground, this is to ensure that all your breast tissue is measured. Place the tape measure at the fullest part of your breast tissue

2. Ensure the band of the non-padded bra you are wearing is parallel to the measuring tape. Make sure that the tape measure is not too tight

3. Note down the measurements at the tightest setting

4. Now subtract the size of the band you recorded earlier from the size of your bust to get the correct current bra size guide from your cup size measurements. Match the difference between bust size and band size using the size chart below to arrive at your cup size.

Difference (Bust-Band)Cup Size
12.54A cup
25.08B cup
37.62C cup
410.16D cup
512.70DD cup
615.24DDD cup
717.78F cup
820.32G cup
922.86H cup
1025.40I cup
1127.94J cup
1230.48K cup

Your bra size then should be the measurement on your rib band and the letter matching your cup size. For example,  if your rib band measurement was 34 and the letter matching your cup size was B, your bra size is 34B. Larger sizes e.g. DDD can match with size F.

Note that mammary glands shrink hence breasts do actually reduce in size after breastfeeding. It would be ideal to repeat the cup measurements again, after breastfeeding that is.

How to measure your shoulder size

Shoulder size measurements are inevitable for the perfect size fit for a nursing bra. You will need a friend to help you get the right measurements as you stand upright.

Here is how to go about the measurements;

1. Instruct the person helping you to place the edge of the tape measure at the joint where the top of your arm and the shoulders meet. This should be the boniest part of your shoulders

2. Let them stretch the tape right across the tip of the boniest part of the other shoulder

3. Note the measurements down. That is your shoulder width.

Plus Sized Nursing Bra Size for breastfeeding


FC=Full Cup | Designed for women with full cups and smaller bands. Covering cup sizes G-J and band sizes 30-40.

Valuable Tips Worth Noting About Breastfeeding Bras

A breastfeeding bra is going to play such a critical role during your breastfeeding journey. Please take note of the following to ensure comfort as you go through this important period; 

  • The cup size is not all you need to determine your right bra size! Most women wear a nursing bra that is too large in the back and with small cups
  • An ill-fitting maternity bra might cause infections on the breasts due to clogged ducts.
  • A supportive nursing bra is one of the most essential requirements during the  motherhood maternity journey as it will ensure your breasts remain healthy during the whole period of breastfeeding
  • Always use a bra for nursing as it will enable you to get quick access to the breasts when breastfeeding
  • Do not choose a larger cup size than your correct size as it will be uncomfortable at the end of it. Invest in bras with larger flanges for comfort
  • Check for bras with an adjustable bra strap for strap adjustment, or a bra extender in case of overly fuller breasts when milk production is too much and the baby is not able to exhaust.
  • Invest in nursing clips and breast pumps. An electric breast pump will help you express milk for storage.  pumping using a hands-free pumping bra will enable you to collect more milk.
  • People with larger busts should go for wider straps as they are great for comfort
  • Fluctuations in breast size are normal depending on the stages of nursing
  • Always consult a lactation consultant or a nursing salon when you notice something unusual besides the normal fluctuations in breast size during breastfeeding
  • Breast size is slightly smaller during pregnancy than when breastfeeding where you have a fuller breast
  • Always wear a bra with wider straps, adjustable straps, smooth shape,  and larger band size during the breastfeeding period 
  • A fabric expert will advise you to  invest in a bra with a soft cotton lining as nipples tend to be irritable
  • If a bra shoulder strap keeps falling over then that is the wrong bra size
  • Invest in a maternity sports bra of the right size fit if you work out during lactation. You can check options online, for example, Amazon


Milk production is at its peak during the first weeks of nursing, so please make advance plans to shop for a nursing sleep bra as it comes with nursing pads that prevent milk leaks. If you are having trouble accessing a comfortable breastfeeding bra during pregnancy or lactation, you can always check online on popular platforms such as Amazon or talk to a nursing specialist. They come in a wide range of sizes, so you should be able to find the perfect size for you.

Do you have any questions? Kindly drop them in the comments section and don’t forget to share this article with your friends too. We wish you all the best in this journey to motherhood!

Photo by @lilliesandleon, via Instagram (nursing bra by Cake Maternity)

Other dedicated Bra size charts