Types of Mice in the UK and How to Tell Them Apart

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Four wild mouse species live in the UK: the house mouse, the field mouse (also called the wood mouse), the yellow-necked mouse and the harvest mouse. Only the house mouse lives indoors all year. Field mice and, in southern England, yellow-necked mice come in from gardens and woods in autumn and winter, while harvest mice stay outdoors. Two dormice also live here, and voles and shrews are often mistaken for mice.

UK mouse identification chart

The House Mouse (Mus domesticus)

The house mouse is the mouse you’re most likely to find in a UK home. It lives in buildings all year round and is found across Great Britain and Ireland.

• Size: 7 to 9 cm long, with a tail about as long again. Adults usually weigh under 25 g.
• Colour: grey-brown all over, including the belly, which is only slightly paler.
• Features: small eyes and ears compared with a field mouse, and a scaly, almost hairless tail.
• Where: kitchens, lofts, wall cavities and under floors, close to food.
• Diet: cereals and grain first, then almost anything. See what mice eat.

House mice are active at night, climb well and breed all year indoors, so numbers build up quickly. They also leave a strong, musty smell where they’ve been for a while.

How does the house mouse affect humans?

It spoils food and damages your home. House mice leave droppings and urine wherever they feed, which can carry germs such as Salmonella and Listeria, and they gnaw packaging, wood and electrical cables. Here’s how to clean up mouse droppings safely.

The Yellow-Necked Field Mouse (Apodemus flavicollis)

The yellow-necked mouse looks like a large field mouse with a band of yellow-brown fur across its chest. It’s found only in parts of southern Britain, from Dorset across to Kent and Suffolk, and along the Severn from Gloucestershire to Staffordshire, usually near old woodland.

• Size: 9.5 to 12 cm long, with a tail of 8 to 12 cm. It weighs 14 to 45 g, making it the UK’s biggest true mouse.
• Colour: brown on top and white underneath, with the yellow band across the chest.
• Where: woodland, hedgerows and gardens. It climbs well and sometimes nests in houses.

How does the yellow-necked mouse affect humans?

Where they live, yellow-necked mice sometimes move into lofts and roof spaces in autumn, where they’re noisy and chew stored items. Like field mice, they can’t be controlled with poison, so traps and blocking the way in are the answer.

Field Mouse (Apodemus sylvaticus)

The field mouse, also called the wood mouse, is the UK’s most common wild mouse. It lives in woods, fields, hedgerows and gardens almost everywhere, and moves into sheds, garages and homes when the weather turns cold.

• Size: 8 to 10 cm long, with a tail of up to 10 cm.
• Colour: chestnut or sandy brown on top, with a clean white belly.
• Features: big, bulging eyes, large ears and long back feet for jumping.
• Where: gardens, sheds, garages and the edges of houses, especially in autumn and winter.
• Diet: seeds, nuts, berries, fungi and insects.

What does a field mouse look like?

A field mouse is browner and brighter than a house mouse, with a sharp line between its brown back and white belly. Its eyes and ears look too big for its head, and it hops rather than scurries. Wood mice are also known to mark their route with small objects such as leaves and twigs, a habit no other UK mouse shares.

How big do field mice get?

Up to about 10 cm, not counting the tail, and around 13 to 27 g. Including the tail, a big field mouse can measure close to 20 cm.

How does the field mouse affect humans?

Field mice raid stored seed, bulbs and bird food, dig up newly planted bulbs and peas, and nest in sheds and lofts. Indoors, they chew food packets just like house mice. One important difference: no mouse poison is approved for use on field mice, so they have to be caught with traps. See how to get rid of mice for what works.

Harvest mouse (Micromys minutus)

The UK’s smallest mouse, at 5 to 7 cm, with golden fur, a white belly and a tail it uses to grip stems. It weaves ball-shaped nests in tall grass, reed beds and hedgerows. Harvest mice don’t come into houses, so if you have mice indoors, it isn’t this one.

Dormice: hazel and edible dormouse

Dormice aren’t true mice, but they’re often confused with them.

• Hazel dormouse: 6 to 9 cm, golden, with big black eyes and a fluffy tail. It lives in woodland and hedges, sleeps through winter and is protected by law.
• Edible dormouse: much bigger, at 12 to 17.5 cm, grey-brown with a bushy tail, so it looks like a small squirrel. In the UK it’s found only in the Chilterns, mostly within about 35 km of Tring, and it often lives in lofts of occupied houses, where it’s noisy at night and chews wiring and stored things.

A field mouse is much smaller than either dormouse, with a thin, scaly tail rather than a furry one.

Field mouse vs house mouse: how to tell them apart

The quickest checks are the belly and the face. A white belly and big eyes and ears mean a field mouse; grey-brown all over with smaller ears means a house mouse.

Where you see it helps too. A mouse in the kitchen in summer is almost always a house mouse. A mouse in the shed, garage or a ground-floor room after the first cold nights is often a field mouse.

How do I tell what kind of mouse I have?

• Look at the belly: clean white means a field or yellow-necked mouse; grey-brown means a house mouse.
• Check the chest: a yellow band means a yellow-necked mouse.
• Look at the eyes and ears: big and bulging means a field mouse.
• Watch how it moves: field mice hop and jump; house mice scurry along walls.
• Think about where and when: house mice are indoors all year; field mice arrive in autumn and winter.

Droppings won’t tell you which mouse you have: both leave dark droppings about 3 to 6 mm long. They do tell you where the mice are active. Check the signs of mice in your house, and see where mice like to build a mouse nest.

How Are Mice Different Than Rats and Voles?

Voles and shrews are the animals most often mistaken for mice. Voles have shorter, blunter faces, small ears and short tails, and they live outdoors in long grass and gardens. Shrews have long, pointed, twitching noses and tiny eyes. Neither usually comes into houses.

Rats are much bigger. An adult brown rat’s body is about 23 cm long, with a thick tail and a blunt nose, and its droppings are 12 to 18 mm, three times the size of a mouse’s. A young rat can look like a big mouse, but its head and feet look too large for its body. Here’s more on the difference between mice and rats.

What colour are mice?

Wild UK mice are shades of brown and grey. House mice are grey-brown all over. Field mice are chestnut or sandy brown with a white belly. Yellow-necked mice are brown with a yellow chest band, and harvest mice are golden. White, black, cream and patterned mice are pet mice, bred from house mice in many colours.

Are there black mice in the UK?

Not in the wild. A mouse that looks black in your house is usually a dark grey-brown house mouse seen in poor light, or a young rat. Outdoors near ponds and streams, a small black animal with a pale belly and a long, pointed nose is likely to be a water shrew. Black mice sold as pets are bred house mice.

Brown mouse or grey mouse?

A grey or grey-brown mouse with a belly almost the same colour is a house mouse. A warmer, reddish or sandy brown mouse with a white belly is a field mouse. Very dark brown mice are usually house mice, as their colour varies a lot.

How many types of mice are there?

In the UK, four wild mouse species: house, field (wood), yellow-necked and harvest mice. Add the hazel and edible dormouse and you have six mouse-like animals. Worldwide there are hundreds of species, and the house mouse has spread to almost every country with people.

What about pet mouse breeds?

Pet or “fancy” mice are all house mice, bred over many years for different colours, markings and coats, such as long-haired, satin or curly. They’re the same species as the mice in your kitchen, just tame.

What makes mice dangerous to homeowners in the UK?

Mostly the mess they make and the damage they cause:

• Food: mice spoil far more food than they eat, leaving droppings and urine as they feed.
• Germs: droppings and urine can carry Salmonella and Listeria. Leptospirosis can be spread in mouse urine too, but it’s rare in the UK.
• Fire risk: mice chew the plastic coating on electrical cables.
• Damage: they shred insulation, chew furniture, boxes and stored clothes for nests, and dig up bulbs in the garden.

You may also read about hantavirus. In the UK it’s linked to rats rather than mice, and the risk is very low. Here’s more on hantavirus and UK rodents.

How to keep mice out of your home

• Store food in sealed tins, jars and tubs, and clear up crumbs before bed.
• Keep pet food and bird seed in metal or hard plastic bins.
• Clear piles of cardboard, newspapers and old clothes from the loft, garage and under the stairs.
• Seal gaps around pipes, cables and vents, and fit brush strips under doors.
• Keep sheds and garages tidy, as field mice move in from there.

If mice are already inside, see how to get rid of mice in the walls, or get a professional in.