Chickenpox and School: When Can They Go Back?

My School Agent | 8 July 2026

The first spot appeared on a Sunday night. Right there on his back, small and red with a tiny blister in the middle.

I Googled "chickenpox spots" and compared images. Then I Googled "when can child return to school after chickenpox" and got seventeen different answers ranging from "when all spots have crusted over" to "after two weeks" to "once they feel better."

The NHS is clear on this. The internet is not.

The NHS Rule: 5 Days After Spots Appear

Your child can return to school once all the chickenpox spots have crusted over. This usually takes about 5 days from when the spots first appeared.

Not 5 days from when you noticed them. From when they actually appeared. If you spotted the first spot on Monday evening but it probably started Monday morning, count from Monday.

All the spots must be crusted over. Not just most of them. If there are still fresh blisters, they're still contagious.

What "Crusted Over" Looks Like

Fresh chickenpox spots are red with a small fluid-filled blister on top. The blister is clear or slightly cloudy.

After a day or two, the blister bursts or deflates. A crust forms over the top. The spot is no longer raised and squishy. It's dry and scabby.

Crusted spots can still be red and sore-looking. That's fine. The key is that there's no fluid left. Once the crust is there, the spot is no longer infectious.

New spots can appear for up to 5 days after the first one. So even if the first spots have crusted over, your child might still be sprouting fresh ones. You need to wait until every single spot is crusted.

Calling the School

Ring the school on the morning of the first day your child is off. Tell them it's chickenpox. They'll record it as an authorised absence.

Some schools ask you to let them know once all the spots have crusted and your child is returning. Others don't. Check what yours prefers.

Schools sometimes send a letter or text to other parents alerting them that chickenpox is going around. This helps parents of children who haven't had it yet (or who are pregnant, or immunocompromised) take precautions.

What About Siblings?

If your child has chickenpox, their sibling who hasn't had it yet will almost certainly catch it.

The sibling can still attend school while waiting to see if they develop symptoms. Chickenpox is only contagious from 1-2 days before the rash appears. You won't know they have it until the spots show up.

Once the sibling develops spots, they follow the same 5-day exclusion rule.

If you have two children and they both get chickenpox, they won't necessarily get it at the same time. The incubation period is 10-21 days. You might have one child off school, then a week of normality, then the second child off school.

This is one of the less enjoyable aspects of parenting.

Nursery vs School

The NHS exclusion guidance is the same for nursery and school. But nurseries sometimes have stricter policies.

Some nurseries ask for a full week off regardless of when the spots crusted over. Others want a doctor's note before the child returns. Others follow the NHS guidance exactly.

Check your nursery's illness policy. It's usually in the parent handbook or on their website.

Treating Chickenpox at Home

There's no cure for chickenpox. It just has to run its course. But you can make your child more comfortable.

Calamine lotion on the spots helps with itching. Apply it with cotton wool, let it dry, reapply as needed.
Paracetamol for fever and discomfort. Follow the dosage instructions for their age.
Cool baths can soothe itchy skin. Pat them dry gently. Don't rub.
Keep fingernails short to reduce scratching and scarring risk.
Loose cotton clothing is less irritating than tight or synthetic fabrics.

Do not give ibuprofen to a child with chickenpox. It's been linked to serious skin infections. Stick to paracetamol.

When to Call the GP

Most cases of chickenpox don't need medical treatment. But call your GP or NHS 111 if:

Your child is under 4 weeks old
Your child has a weakened immune system
You're pregnant and you've been exposed to chickenpox (and you've never had it yourself)
The spots become red, hot, or painful (sign of infection)
Your child has a very high fever that won't come down
Your child is unusually drowsy or confused

The Second Time Around

Most people only get chickenpox once. Your immune system remembers it. But it's possible to get it twice, especially if the first infection was very mild.

The virus stays dormant in your nervous system after chickenpox. Decades later, it can reactivate as shingles. That's a different illness with different rules.

My son had chickenpox in Reception. It was five days off school, calamine lotion everywhere, and a surprise rewatch of every Pixar film. Then it was over.

I built My School Agent to handle the organisational chaos that piles up when your child is off sick. The homework they missed, the costume day you forgot about, the form that was due yesterday. It won't cure chickenpox. But it'll make sure nothing else falls through the cracks while you're counting crusted spots.