Flat Diapers 101: How to Use Them and Why They’re a Cloth Diapering Classic

In a world of fancy, modern cloth diapers, flat diapers might seem old-school—but don’t let their simplicity fool you. Flats are one of the most versatile, budget-friendly, and effective cloth diapering options out there. They’re especially loved for their quick drying time, customizable absorbency, and ability to grow with your baby from newborn to toddler.

So, what exactly is a flat diaper, and how do you use one? Let’s break it down.

What Are Flat Diapers?

Flat diapers are a single layer of large, square or rectangular cloth—typically made of cotton, bamboo, hemp, or muslin. Think of them as the OG cloth diaper: lightweight, trim-fitting, and endlessly adaptable.

Unlike prefolds or fitted diapers, flats don’t come with sewn-in layers or elastic. Instead, you fold them yourself to fit your baby’s body and diapering needs.

Why Choose Flat Diapers?

  • One-size fits all: With the right fold, flats work from birth to potty training.

  • Super fast drying: Because they’re only one layer, flats air dry in record time—great for line-drying or travel.

  • Affordable and durable: A dozen flats can last for years, and they’re one of the most budget-friendly cloth options.

  • Customizable absorbency: You can double or layer folds exactly where your baby needs it most.

  • Easy to wash: Flats are easy to get clean, even with hand-washing or low-water machines.

How to Use Flat Diapers

Using flats is simple once you get the hang of folding. Here’s what you’ll need:

  • Flat diaper(s)

  • Snappi, Boingo, or diaper pins (optional, depending on fold)

  • Waterproof or wool cover

  • A clean surface to fold on

Step-by-step:

  1. Fold the diaper to fit your baby (see folding styles below).

  2. Secure the diaper with a fastener if needed.

  3. Add a cover for waterproof protection.

  4. Change regularly just like any cloth diaper—every 2–3 hours or when soiled.

Popular Flat Diaper Folds

There are many ways to fold a flat, and once you know a few, you can adjust depending on your baby’s size, age, and absorbency needs.

1. Pad Fold (a.k.a. Tri-fold)

  • Best for: Fast diapering, inserts in pocket diapers or covers

  • How: Fold the flat into thirds lengthwise, then in half to create a long, narrow pad. Lay in a cover or stuff into a pocket.

  • Pros: Super simple, no fasteners needed

2. Origami Fold

  • Best for: Newborns to toddlers, full coverage with front absorbency

  • How: Fold into a square, then fold in a triangle. Fold up the bottom point, then bring in the sides like wings.

  • Pros: Adjustable and trim; good for babies of all sizes

3. Airplane Fold

  • Best for: Heavy wetters, boys, or tummy sleepers

  • How: Focuses absorbency in the front by folding the flat in a rectangle, then forming “wings” to wrap around the waist.

  • Pros: Great absorbency up front; trim on the bum

4. Jo Fold

  • Best for: Toddlers or chunkier babies

  • How: Start with a triangle and fold the top point down to add absorbency in the wet zone, then wrap and tuck.

  • Pros: Offers more absorbency in the middle

5. Kite Fold

  • Best for: Babies needing even absorbency

  • How: Fold into a kite shape, bring the bottom up, and wrap the wings.

  • Pros: Versatile, classic shape with great overall fit

Tips for Success with Flats

  • Prep flats before first use: Natural fiber flats need several washes to reach full absorbency.

  • Use boosters if needed: You can layer a second flat or add a booster for naps or heavy wetters.

  • Practice makes perfect: Folding gets easier with a little muscle memory—try a few folds and see what works best for your baby.

  • Pair with the right cover: Flats work beautifully under wool or PUL covers.

The Bottom Line

Flat diapers may be simple, but they’re a powerhouse in the cloth diapering world. With a little folding know-how, they can handle anything from newborn blowouts to toddler overnights. Whether you're building a minimalist stash, looking for the most eco-friendly option, or just love the idea of diaper origami—flats are a timeless choice that keep things clean, comfy, and cost-effective.