How do I choose the sizes of matching pyjamas for the whole family?

Measure everyone, children included, and choose by height in centimetres rather than by age or usual clothing size. Between two sizes, take the larger one for an adult; for a child, above all check that the legs don't drag on the floor.

Is a onesie suitable for a young child?

Yes, as long as it's the right size, without legs so long they trip, and an adult keeps an eye on them, especially on the stairs and near sources of heat. For toddlers, follow the sizes set by the manufacturer and don't go beyond their range.

Do we all have to wear exactly the same style?

No. The same animal in different sizes gives the clearest ‘family’ look in photos, but you can also play on the same colour or the same theme with different styles, for example a monster onesie for the adults and an animal for the children.

When should I order matching pyjamas for Christmas?

As early as possible: you need time to measure everyone, receive the onesies and, if necessary, exchange a size before the holidays. Best to avoid the last week before Christmas.

October 4, 2026 · 4 min read

Matching family Christmas pyjamas: how to get them right

Style, kids' and adult sizes, fabric, safety for little ones: the practical guide to dressing the whole family in the same pyjamas for Christmas.

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matching christmas pyjamas
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Matching family pyjamas make the Christmas photo everyone brings out again every year. For it to work (and for nobody to spend the evening hitching up legs that are too long), three things matter: a style that comes in kids' and adult sizes, sizes chosen to the centimetre, and a few basic precautions for the youngest.

Why the one-piece onesie works so well for families

A matching top and bottom is nice. A hooded onesie with ears is a silhouette: you recognise the "tribe" at first glance, even in a photo taken from across the room at the foot of the tree.

Another, very practical advantage: a roomy onesie goes on over a T-shirt and comes off just as fast. On the morning of the 25th, you pull it on as you get out of bed, and it keeps you warm while the presents are opened.

If you're still torn between several formats, our comparison classic onesie or Monster Pyjamas sets out the differences.

Step 1: choose a style that comes in everyone's size

The classic trap: finding an adorable style in an adult size, then discovering it doesn't exist for children. Before you give in to temptation, check that the same item covers every size you need.

That's the idea behind the Family Fleece Onesie: the same animal (panda, ginger tiger, brown bear, dinosaur or capybara) in kids', women's and men's sizes. Each size is ordered separately, so you put together exactly the family you have.

Fancy a quirkier look for the adults? The Monster Pyjamas, with their horned hood, can happily do their own thing: parents as monsters, children as animals, and the look still hangs together.

Step 2: measure everyone

Don't go by the children's ages or the adults' jeans size. Onesie size guides are read by height, in centimetres (and sometimes by weight for kids' sizes).

Measure standing up, barefoot, back against the wall. A ruler flat on the head, a pencil mark, then measure from the floor to the mark.
Write down each measurement before opening the size guide, so you don't "round" by guesswork.
Adults between two sizes: take the larger one; the cut is designed to be roomy.
Children between two sizes: take the one that matches their current height rather than "buying big for next year". Legs that are too long make them trip.

We explain the method in detail in our guide to choosing your adult onesie size.

Step 3: think about the youngest

Party pyjamas are still clothes children wear to run around in. A few simple habits:

The right size. No legs or sleeves hanging over: that's the main cause of falls on the stairs.
Away from flames. Like any synthetic fabric, fleece must be kept away from candles, the fireplace and the stove. On Christmas Eve, that's the thing to watch.
No overheating at night. A fleece onesie is warm: if the child sleeps in it, keep the bedroom cool and avoid adding a thick duvet on top.
An adult close by. Zips, hoods, getting dressed and undressed: for the littlest ones, an adult helps and keeps watch.
Stick to the sizes provided. Don't dress a child who is smaller than the smallest size available in a onesie that's too big.

Step 4: get ready for the photo

A few ideas to make sure the picture lives up to expectations:

Wash the onesies before the big day. A first wash at 30 °C on a delicate cycle softens the fleece and gets rid of that "straight out of the box" look. It's all explained in our guide to washing fleece pyjamas.
Hoods up. It's the ears that make the photo.
Soft light. Fairy lights in the background, a lamp to the side: avoid direct flash, which flattens the fabric.
Remember the dog or cat. They won't wear the onesie, but they'll want to be in the photo.

Mistakes to avoid

Ordering at the last minute. You need time to receive them, try them on and, if necessary, exchange a size before the holidays.
Buying everything "roughly right". Get just one size wrong and someone's missing from the photo.
Choosing a fabric that's too thin. For pyjamas you'll keep all winter, thick fleece goes the distance. Our comparison of winter pyjama fabrics will help you decide.

In short

A style that comes in everyone's size, a measurement in centimetres for each person, the right size and an attentive adult for the youngest: with that, matching pyjamas become the Christmas tradition you keep from one year to the next. And once the photos are done, there's the whole winter left to enjoy them, for example at a grown-up pyjama party.

Cover photo: Bare Kind / Unsplash