Plant Life

How Many Newborn Onesies Do I Need?

Preparing for a newborn and wondering how many onesies to get? Read on for our insights.

Newborn onesies
baby clothing packed into a bag

Rent organic baby clothes from premium brands for a fraction of the price


When creating UpChoose baby clothing sets, onesies are our top pick. We've prepared these sets for thousands of new parents, focusing on newborn size clothes and the essentials of a newborn clothes checklist. We generally include 8-10 onesies for the newborn and early months sizes. Here, we share our learnings with you, so you don't have to spend hours searching.

Having a newborn is exciting. It brings joy, hope, and lots of planning. As a new parent, you're likely to find yourself immersed in a sea of newborn outfits and questions about baby clothing sizes, trying to figure out the perfect baby registry or newborn clothing checklist. One question that will quickly pop up is: "How many newborn onesies do I need?" This question might seem simple, but the answer can vary depending on several factors such as the season your baby is born, your laundry routine, and your baby's growth rate.

At UpChoose, we understand the importance of providing your little one with comfortable, sustainable, and high-quality newborn outfit choices. We also know that navigating the world of newborn size clothes can be overwhelming, especially for first-time parents. That's why we've put together this comprehensive guide to help you estimate the number of onesies you'll need for your newborn.

You can also see how many onesies we include in our bundles by taking our style quiz.

Clearing the Confusion: What Are Onesies?

Before we delve into the number of onesies you need, let's first clarify what onesies are. People often use "onesie" and "bodysuit" to mean the same thing for baby outfits. Both are one-piece clothes that cover the body. They fasten with snaps or buttons. They come in various styles, including short sleeve, long sleeve, and kimono styles.

UpChoose baby wearing a short sleeve onesie
UpChoose baby wearing a short sleeve bodysuit

Onesies are a fundamental part of a baby's wardrobe, offering comfort and ease for both the baby and the parents. They are designed to be worn alone in hot weather or layered under other baby outfits, or paired up with baby pants in cold weather. Onesies are great for nap time, play, or going out. They fit many of your baby's needs.

Different Types of Onesies

There are many types of onesies out there. Each has its own purpose. Here are some of the most common types:

Short Sleeve vs Long Sleeve Onesies

Short sleeve onesies are great for warm days or to wear under other clothes. They are a staple in any baby clothes checklist, especially for those living in warmer climates. Long sleeve onesies, also known as sleeve onesies, are ideal for colder weather or for providing extra protection to your baby's arms. They can be worn alone or layered under other clothing items.

UpChoose onesies 1
Short sleeve vs long sleeve onesies by Colored Organics (included in UpChoose sets)

Envelope vs Kimono Onesies

Envelope onesies have a wide neck. You can pull them down over the baby's body. This makes changes easy, especially if it's messy. Kimono onesies, on the other hand, are designed with a wrap style, making them easier to put on and take off. They are especially useful during the early weeks when your baby's umbilical cord stump is still healing.

UpChoose onesies 2
Envelope vs Kimono onesie by Colored Organics and L'ovedbaby (included in UpChoose sets)

Onesies with Integrated Mittens

Onesies with integrated mittens have fold-over flaps on the sleeves to cover the baby's hands. These are great for preventing newborns from scratching their delicate skin. They also keep little hands warm and are a handy alternative to separate mittens that can easily get lost.

upchoose bodysuit with mittens
Onesies with Integrated Mittens by L'ovedbaby (included in UpChoose sets)
💡 What we include in UpChoose sets

We generally include 8-10 onesies for the newborn and early months sizes. We always include at least some long sleeve onesies in our sets for skin protection from the sun. Many new parents like to use kimono bodysuits for the first few weeks. For example, most of our Full Sets for the newborn and 0-3m size would include 5 long sleeve bodysuits and 5 short sleeve bodysuits, and many will have Kimono opening.

You can see what we include in our bundles by taking our style quiz.

What About Baby Clothes Sizes?

Is there a set number of onesies for each size? No. In fact, just having a number doesn't give the full picture. It's essential to understand that the number of onesies you might need can vary significantly between baby clothing sizes. For instance, while newborn sizes clothes might be outgrown quickly, requiring fewer onesies, your baby might stay in another size for a longer duration, necessitating more. The goal is to strike a balance: you don't want to end up with too many onesies for one size and not enough for the next.

Baby clothes sizes vary. Newborn sizes usually fit babies up to 8 pounds, but brands can differ. The key is flexibility. It's about ensuring you have just the right amount for each size and being ready to size up when needed.

You'll need to plan ahead and be ready to change. If this sounds overwhelming, that's where UpChoose steps in. We've tailored our service to ensure you have the right amount for each stage, and we adjust based on your baby's unique growth pattern.

How Many Onesies Do You Need?

What you'll find online

Looking online, you'll see there's no single answer for everyone. Take, for example, a Reddit thread on the r/BabyBumps subreddit where expecting parents discuss how many clothes of each size to buy. The numbers are all over the place. Some parents suggest stocking up on newborn sizes, while others recommend focusing on 0-3 months or even larger sizes.

This variability underscores an essential point: while it's beneficial to gather insights from others, you're often reading about what worked for someone else's unique situation. Every baby and family is unique. Use online advice as a guide, then adjust for your situation.

Reddit onesies

UpChoose's Data Insights

Data from many UpChoose parents shows 8-10 onesies work well for the first size. This is what we include in UpChoose baby clothing essentials bundles and has proven to work well for the majority of cases. Of course, this can vary based on individual circumstances, including factors like access to in-house laundry facilities. Remember, babies grow quickly, and overstocking on the first sizes can lead to unnecessary waste as these are often only used for a few weeks. It's about finding a balance between having enough for your baby's needs and avoiding excess.

Want to get curated sets of premium organic baby clothes at a fraction of the retail price?

Step 1 — Design your set

Take the style quiz to design your set and add your preferences.

Step 2 — Enjoy

Enjoy the softest organic baby clothes.

Step 3 - Swap

Swap for the next size up when needed. Shipping is always free.

Factors Influencing the Number of Onesies You Need

Many things can change how many onesies your newborn needs. Let's delve into these factors to help you make an informed decision:

  • Season: The baby's birth season can change how many onesies you need. If your baby is born in summer, you might need fewer long-sleeved onesies and more short-sleeved or sleeveless ones. Conversely, if your baby is born in winter, you might need more long-sleeved onesies to keep your baby warm.

  • Baby's Growth Rate: Babies grow at different rates. Some babies might outgrow their newborn sizes within a few weeks, while others might fit into them for a couple of months. It's essential to monitor your baby's growth and adjust the number of onesies you have accordingly.

  • Laundry Routine: Your laundry routine can also influence the number of onesies you need. If you do laundry frequently, you might need fewer onesies. However, if you do laundry less often, you might need more onesies to ensure you always have a clean one on hand.

What to Look for When Shopping for Onesies

When shopping for newborn onesies or looking for newborn baby clothes to add to a baby registry, there are three main criteria to consider: quality of materials, ease of use, and comfort.


Choose onesies made from high-quality, soft, and breathable fabrics. Organic cotton is a great choice as it's gentle on a baby's sensitive skin and is more sustainable than conventional cotton. Avoid synthetic fabrics like polyester, which are not as breathable and can contain chemicals and dyes that may irritate a baby's sensitive skin or cause allergic reactions.

Ease of Use

Look for features like envelope necklines and snap closures for easy dressing and diaper changes. In our baby clothing essentials bundles, new parents can customize their selection and many request kimono onesies with open closures, which are particularly easy to put on and take off.


Ensure the onesies are roomy enough for your baby to move around comfortably. Having some long sleeves, especially in the newborn stage and early months, can provide added skin protection from the sun when outdoors.

UpChoose's Selection of Clothing Brands

At UpChoose, we curate adorable outfits from premium organic cotton clothing brands. Here are some of the brands we feature:

  • Colored Organics: This brand offers a variety of onesies in vibrant colors, all made from organic cotton.

  • Parade Organics: Offers a wide range of organic baby clothing, from onesies and sleepers to rompers and dresses, made from certified organic cotton and using eco-friendly dyes.

  • L'ovedbaby: Offers a range of organic cotton onesies in a variety of styles and colors.

  • Pehr: Provides a broad selection of baby items, including sleepwear, playmats, and nursery decor, committed to both style and environmental stewardship

  • Kate Quinn Organics: Their onesies are designed with practical features like envelope necklines and snap closures for easy dressing and diaper changes.

  • Under The Nile: Known for their organic cotton onesies that are soft, durable, and gentle on your baby's skin.

  • Hanna Andersson: Known for their high-quality, durable baby clothes.

  • Monica & Andy: Offers a range of stylish and comfortable onesies made from organic cotton.

  • Finn + Emma: Offers a range of colorful and fun onesies made from sustainable materials.

  • Burt's Bees Baby: Known for their natural, organic baby products, their onesies are no exception.

Each of these brands shares UpChoose's commitment to creating a more sustainable future for our little ones, one clothing item at a time.


Determining the number of onesies you need for your newborn can be a daunting task, especially for first-time parents. However, with the right information and guidance, you can make an informed decision that suits your baby's needs and your lifestyle. Remember, the goal is not to have an excess of onesies but to have enough to keep your baby comfortable and happy.

At UpChoose, we're here to help you navigate this exciting journey. Whether you're preparing for a baby shower, setting up your baby registry, or just stocking up on baby clothes, we've got you covered. Our baby clothing essentials bundles are designed to provide you with all the onesies you need for your newborn, without the stress and hassle of shopping. Plus, with our selection of premium brands, you can be sure that your baby is wearing the best.