When to get help

Call emergency services — 999 in the UK, 112 or 999 in Ireland and across the EU, 911 in the US and Canada, 000 in Australia, 111 in New Zealand — if a neck lump comes with difficulty breathing, a noisy sound on breathing in, drooling with an inability to swallow, a stiff neck with fever, a rash that does not fade under a glass, or a baby who is floppy or hard to wake.

Seek same-day advice — NHS 111 in the UK, GP or out-of-hours in Ireland, paediatrician in the US or Canada, healthdirect on 1800 022 222 in Australia, Healthline on 0800 611 116 in New Zealand — if:

The lump is red, hot and tender, or the skin over it is shiny, which suggests the gland itself is infected.
The lump is growing quickly over days.
There is a fever, particularly in a baby under three months at 38°C or higher, which NICE guideline NG143 places in the high-risk group.
Your baby is holding their head to one side and will not straighten it.
Feeding has dropped off, or your baby seems generally unwell.

Book a routine appointment if a lump is hard, does not move under the skin, is bigger than about two centimetres, is still there after four to six weeks, is one of several appearing in different places, or comes with night sweats or poor weight gain. The NHS makes the same distinction: most lumps are harmless, but a lump that is getting bigger, feels hard, does not move, or comes with a fever or weight loss should be checked.

Why babies have palpable glands

Lymph nodes are part of the immune system, and they sit in chains down the sides of the neck, under the jaw, behind the ears and at the back of the head. When they meet something to react to, they enlarge. Babies and young children meet a great many new infections in a short space of time, so their nodes are active almost constantly.

The result is that small, pea-sized, soft, movable lumps are extremely common and often entirely normal findings. The American Academy of Pediatrics notes that swollen glands in children are usually a response to infection. Parents often find them for the first time while washing a baby's neck, and the lump has usually been there for a while.

What a reactive gland feels like

Soft or rubbery. Movable — it rolls slightly under your fingertip rather than being fixed to the tissue underneath. Usually under a couple of centimetres. Often several, and often on both sides. Not hot, and not making your baby cry when touched, though it may be mildly tender in the middle of an infection.

Timing helps: reactive glands come up during or just after a cold, an ear infection, a sore throat, a scalp infection or cradle cap, teething, or a skin infection nearby. They then shrink slowly, and they often take several weeks to settle. A gland that has been slowly getting smaller for a month is doing exactly what it should.

The lumps that are not glands

Not every neck lump is a lymph node, and some have their own patterns.

A firm lump within the muscle at the side of the neck in a young baby, often with the head held tilted to one side, suggests a sternocleidomastoid tumour of infancy, which despite the name is a benign area of fibrous tissue associated with torticollis. It is treated with physiotherapy and it usually resolves.

A smooth, painless lump in the midline of the neck that moves upwards when a baby swallows may be a thyroglossal cyst. A soft lump towards the front or side that has been present since birth may be a branchial remnant or a cyst. Fatty lumps, cysts in the skin and infected hair follicles all occur too. None of these are emergencies, and all of them need identifying rather than watching indefinitely.

What not to do

Do not squeeze, prod repeatedly or try to drain a lump. Frequent handling makes it sore and makes it harder for you to judge whether it is actually changing. Do not apply heat to a hot, red lump in the hope of bringing it to a head without advice.

Do not measure it every day. Measure once a week at the same time, or better, photograph it next to something for scale. Day-to-day comparisons are unreliable and generate anxiety without adding information.

What to expect at the appointment

Expect the clinician to feel the lump and also all the other node areas, look in the ears, nose, mouth and throat, check the scalp for infection, and feel the tummy. That last one is not incidental: the size of the liver and spleen is part of the picture when generalised gland enlargement is being assessed.

Most cases end there, with a plan to review in a few weeks. If the lump is infected, antibiotics are usual. If there are features that need it, blood tests and an ultrasound are the next steps, and referral follows only if those suggest it. Ask what would count as a reason to come back sooner, and write it down.

What to note before you go

Three facts do most of the work: when you first noticed it, whether it has changed since, and what your baby was unwell with in the fortnight before it appeared. Add whether there has been fever, weight change, night sweating, or any lump elsewhere. Those answers steer the appointment far more efficiently than a description of the lump itself.

A Lump on a Baby's Neck