How To Tell The Difference Between Rats & Mice

16th February 2026

What To Look Out For Between Mice & Rats

Despite both being rodents, rats and mice have some stark differences that can differentiate them, including physical appearance, and the signs they leave behind, like gnaw marks and droppings. Their size and features are the easiest way to tell, as rats are much larger than your typical mouse. If you’ve got a rodent infestation, it’s important to know the difference between mice and rats so you can have a better idea of what you’re dealing with and the measures you can take to help solve the problem.

In this handy guide, we’ll be breaking down what to look out for so you can tell the differences between rats and mice, and what to do if you happen to find an infestation in your home.

What Are The Physical Differences Between Rats & Mice?

Perhaps the easiest way to tell the difference between rats and mice is by their physical appearance. Some key telltale aspects of rodents set them apart from one another, including:

Body Size – Rats tend to be much larger than mice. You common brown rat will typically be around 20-25 cm, whereas a mouse is around 3-10cm.
Tail – Mice will have a thin tail, whereas a rat will have a longer, thicker tail.
Ears – Rats tend to have small ears that will be tucked back, whereas a mouse will have larger, more rounded ears.
Snout – Rats will have a more blunt and rounded snout, compared to mice, which will have a more pointed, triangular snout.

So, if you have seen a rodent running around, you should now be able to tell what it is from the visual signs. But what are the signs to look out for if you haven’t seen the rodent?

What Are The Signs Of A Mouse & Rat Infestation?

You don’t always need to have seen the rodent to know that you have a mouse or rat infestation. You can also distinguish between the two using the signs and evidence that they leave behind. There are typically three indicators:

Droppings – All pests leave droppings. Mice will tend to leave small grains that resemble rice, whereas rats will leave larger, raisin-sized droppings.
Gnaw marks & damage – If allowed to nibble, mice will shred soft materials and leave smaller, neater bite marks. Rats have larger and more powerful teeth, allowing them to chew through stronger materials and leave rougher marks.
Tracks – When travelling around the house, the rodent may leave tracks. Again, mice will leave smaller tracks, and rats will leave larger ones.

So you’ve found out you’ve got an infestation in your house, and with these tips above, you can tell which rodent is making itself at home as an unwanted guest. But now you may be wondering: what’s next?

What Should I Do If I Find Rodents In My Home?

If you find rats or mice in your home, you can always leave traps down at your discretion, but you must sanitise the area you’ve found the signs in (especially if they’re leaving droppings). In our post about how to prevent mice from entering the house, we advise that you also seal up the entry points and provide other tips to prevent a growing infestation.

However, when all else fails, it’s always best to leave it to the professionals so that you can keep your pest problems under control.If you’re looking for more information about rodents and how Ace Pest Control can help with your infestation concerns, then get in touch today by filling out our online contact form or by giving us a call on 01234 838 391.

Common Questions About Rats & Mice

How can I tell if I have rats or mice?

Rats are larger, with thick bald tails and blunt noses, while mice are smaller with thin hairy tails and pointed noses. Rat droppings are also bigger, roughly the size of a grain of rice, compared with the smaller, thinner droppings mice leave behind.

Are rat droppings different from mouse droppings?

Yes. Rat droppings are larger, around the size of a grain of rice with rounded ends, while mouse droppings are smaller, thinner and more pointed. Fresh droppings are shiny and soft, while older ones are dry and crumbly.

Do rats and mice need different treatments?

The general approach is similar, but bait, trap placement and access points often differ because rats and mice behave differently and use different routes into a property. A proper inspection helps identify which species is present so the right method is used.

When should I call a professional about rodents?

If you see droppings, hear scratching in walls or lofts, or spot gnaw marks, it is worth getting a professional inspection quickly. Rodents breed fast, so a small problem can grow into a larger infestation within weeks.