Get

In Your Inbox

Dogster is reader-supported. When you buy via links on our site, we may earn an affiliate commission at no cost to you. Learn more.

How Big Do Westies Get? Average Weight & Growth Chart

West Highland White Terrier standing on rock

The Westie, or West Highland Terrier, is a terrier breed that originated in Scotland and was bred to hunt foxes and other small game. It is a small breed, but what it lacks in size, this fun-loving and affectionate breed more than makes up for in character. Adult Westies weigh between 15 and 21 pounds and measure up to 11 inches at the withers and are usually fully grown by the age of 12 months. With a life expectancy of 12 to 16 years, you will have a full-grown and fully mature dog for up to 15 years.

To ensure healthy growth, provide a good diet of high-quality food and provide 60 to 80 minutes of exercise a day, and if you are concerned with any rapid weight loss or gain, consult a vet to ensure that your West Highland isn’t suffering any illness. Unfortunately, the Westie is prone to several health conditions and some of these can affect the dog’s size and growth rate.

divider dog paws 2 oct 2024

West Highland Terrier Breed Overview

The West Highland White Terrier was first bred in Scotland and used for hunting foxes, badgers, and otters. The breed was also used to hunt vermin. The Westie is a small breed, but it doesn’t lack energy or intelligence. It can excel at agility, which is a good way to provide the physical exercise and mental stimulation that the breed needs.

The Westie is known to be affectionate and loving with family. While it was once bred for hunting, the breed is best known for being a loving companion dog, today, and is rarely used as a working dog. The modern Westie is more likely to be found chasing a squeaky toy around the house than it is to be seen chasing a fox around a field. Like most terrier breeds, the Westie can usually take or leave strangers. They shouldn’t be aggressive or overly cautious around people they don’t know, but they won’t run up to greet new people, either.

The breed is somewhat prone to a number of health conditions. In particular, keep an eye out for joint-related problems like patellar luxation and Legg-Calve-Perthese disease.

While the Westie is unlikely to be aggressive around other animals, they won’t back down from a fight if another dog starts trouble. And, similarly, they may chase cats. While the dog might not be aggressive towards cats, a marauding Westie is enough to cause most cats to run, which only serves to fuel the excitement further.

Westie Size and Growth Chart

West Highland White Terrier
Image Credit: anetapics, Shutterstock

There is no set weight that you can expect a Westie to reach, and much will depend on the genetics of the dog. Similarly, while most reach their adult size by 12 months, some can take a little longer to develop. However, it is handy to have an expected size range so you can ensure your West Highland White Terrier is growing at an appropriate rate, and if they are growing too quickly or too slowly, you can seek help from a vet.

Below is a rough guide to the weight and height of a typical Westie by age. If yours is a little outside the given range, this shouldn’t be too much cause for concern.

Age Weight Range Height Range
3 months 5.5–8 pounds 4–6 inches
4 months 7.5–9.5 pounds 5–7 inches
5 months 9–10 pounds 5–8 inches
6 months 10–12 pounds 6–8 inches
7 months 11–13 pounds 7–10 inches
8 months 12–14 pounds 7–11 inches
9 months 12–15 pounds 7–11 inches
10 months 12.5–15.5 pounds 7–11 inches
11 months 13.5–17 pounds 7–11 inches
12 months 14–20 pounds 7–11 inches

When Does a Westie Stop Growing?

Although every dog develops a little differently, Westies will usually reach their full height by the age of about 8 to 9 months and their adult weight by the age of around 12 months. However, some may continue to put more weight on until they reach the age of 18 months.

Growth does come in bursts, so while you might see a lot of development one month, there may be less development in the next month. If you believe your dog is putting on too much weight, check their size and adjust their diet accordingly. Alternatively, you can speak to a vet to ensure that they are still a healthy weight and to get nutrition and other advice to help manage their size.

If you need to speak with a vet but can't get to one, head over to PangoVet. It's an online service where you can talk to a vet online and get the personalized advice you need for your pet — all at an affordable price!

PangoVet_Mention-in-Content Savings V1

divider dog paws 2 oct 2024

Factors Affecting the Size of Westies

Several factors can affect the size of a dog, but the biggest factor is genetics. Some dogs are genetically predisposed to be at the top end of their size range, while others will be much smaller. Illness can also have an effect, with some conditions causing growth to slow or stagnate. Having your dog spayed or neutered does require that you change exercise levels and feeding amounts after the operation, and if you don’t make the necessary changes, as advised by a vet, this may cause some weight gain.

hand with pill and west highland terrier dog puppy outdoors
Image Credit: LanKS, Shutterstock

Ideal Diet for Maintaining a Healthy Weight

It is possible to feed your dog dry or wet food or even a raw or fresh food diet, and they still develop at the same rate. If feeding dry food, expect to feed about 1 cup a day to adult dogs, but puppies will need more than this. Buy quality puppy food, weigh your puppy, and follow the guidelines according to the actual age and current weight of your puppy.

Also, be sure not to progress to adult food too quickly and before your Westie has finished developing. Generally, puppies move to adult food at around 12 months of age, but if your Westie has finished growing by 10 months, it’s possible to change to adult food then.

How to Measure Your West Highland White Terrier

Measuring a Westie is quite easy. To measure weight, either have your dog stand calmly on the scales while you take a measurement or first weigh yourself and then weigh yourself while holding your dog and subtract the difference to get the weight of your dog. To measure the height of your dog, measure from the floor to the top of the shoulder blades or the whithers.

If you’re in any doubt, you can have the vet weigh and measure the height of your dog when you take them for a check-up.

How-to-Measure-a-Dog
You are free to use this image but we do require you to link back to Dogster.com for credit.

divider dog paws 2 oct 2024

Conclusion

Westies are lively, energetic, and fun little dogs. While they were originally bred to hunt foxes and other small animals, they are most often kept as companion dogs today. They are loving and friendly with family, may be wary of strangers, and may be prone to chasing cats, albeit in a playful rather than aggressive manner.

The breed will reach maturity at about 12 months of age, but some can continue growing until they are 18 months of age, adult Westies generally weigh between 15 and 21 pounds and measure up to 11 inches in height.


Featured Image Credit: Morten Hjerpsted, Pixabay

Want content like this delivered to you?

Sign Up For Our Newsletter

News, insights, expert advice, and everything dog

* By submitting, you agree to our Terms & Conditions and Privacy & Cookies Policy.

How useful was this post?

Click on a star to rate (you can leave written feedback after clicking submit)

Help us improve Dogster for pet parents!

Your feedback really matters.

What did you like about this post? Also how can we improve it?

Join the conversation

Leave a Reply

You’re very welcome to leave a comment or question. Please know that all comments must meet our community guidelines, and your email address will NOT be published. Let’s have a positive and constructive conversation.

Talk With A Vet Online

Peace of mind,
anywhere, anytime

Affordable vet advice

Pet Poison Prevention Awareness Month 2025: How to Prepare

Pet Poison Prevention Awareness Month occurs every March as part of the broader Poison Prevention Month, which is a national effort to raise...

Dutch Smoushond Dog Breed: Info, Pictures, Care & More

The Dutch Smoushond is a small-sized dog native to the Netherlands. This dog was bred to be a ratter in stables and barns....

Who Are the Biggest Dogs in the World? 2025 World Records

Large dogs are often kept for security purposes because their deep barks and sheer size are enough to deter intruders from a property....

How Smart Are Dogs? Vet Approved Facts & FAQ

How much do you really understand about what goes on in your dog’s mind? Are they just imagining their dinner, the neighbor’s cat,...

More related

Pembroke Welsh Corgi vs Pomeranian: Key Differences & Similarities

The Pembroke Welsh Corgi and the Pomeranian are popular breeds. Although they have a few characteristics in common, they are quite different. The...

National Brown Dog Day 2025: When It Is & How It’s Celebrated

National Brown Dog Day is one of the lesser-known days to celebrate throughout the year. It falls on February 2nd each year, and...

Why Does My Dog Walk Away From Their Food? 3 Vet-Reviewed Reasons & What to Do

If you’re noticing that your dog likes to check out their food but doesn’t actually do much eating, it can be extremely frustrating....

Dogs and Children: A Match Made in Heaven

Hi, I’m Allison! Read my introduction to learn more about me and my three mixed-breed dogs from Thailand, Jelly, Lorraina, and Manic. Countless...

Keep reading

Can Dogs Eat Frosted Flakes? Vet-Verified Facts & Nutrition Guide

While Frosted Flakes are a popular breakfast food for both children and adults, they’re not so great for dogs. Frosted Flakes don’t add any nutritional value to a dog’s diet, and the added sugar can lead to health complications if...

Can Dogs Eat Frosted Flakes

Can Dogs Eat Vegetable Oil? Vet-Verified Facts & FAQ

Vegetable oil is used in cooking and found in a variety of products, which may have you wondering if it’s safe for your dog. After all, it’s easy to accidentally give your dog something with vegetable oil without realizing it....

can dogs eat vegetable oil featured graphic Dogster

What Is Animal Digest in Dog Food? Vet Reviewed Benefits & Drawbacks

Animal digest is an ingredient used in dog and cat foods to improve palatability. Dairy products, amino acids, and fats or fatty acids are other traditional palatants (also called flavor enhancers) added to dog and cat foods to make them...

man checking dog food label

Loyall Life Dog Food Review 2025: Pros, Cons, Recalls & FAQ

Review Summary All dog owners are looking for the best nutrition for their dogs in the food they buy for them. There are so many options available today, some with great nutrition and some without. Loyall Life dog food is...

Dogster_Loyall Life Dog Food Review

Can Dogs Eat Eel? Vet-Approved Feeding Facts

Many dogs love fish, whether a fishy food formula or home-prepared salmon or herring. However, when it comes to less conventional types of fish, like eel, it can be hard to know what’s safe and what isn’t. In brief, common...

Can Dogs Eat Eel

8 Best Wet Dog Foods in the UK in 2025 – Reviews & Top Picks

We want to give our dogs the best life, and part of that means providing nutritious food. If you are searching for the best wet food to give your pup or are thinking about switching from dry food to wet,...

shih tzu dog getting wet food from owner at kitchen

Can Dogs Eat Grits? Vet-Verified Nutrition Facts & FAQ

Grits are a popular breakfast staple, especially in southeastern U.S. states. Grits are derived from white corn kernels and are a quick and easy way to grab a little bite to eat before heading out the door in the mornings....

Can Dogs Eat Grits

Is Blue Buffalo Made in the USA? What You Need to Know

Blue Buffalo is a famous dog food brand with many recipes for optimal canine health. There are tons of options in recipes, treats, and other supplements. If you have any kitties—they even have quite a comprehensive cat food line. But...

Is blue buffalo made in the USA?