Border Collie Size Guide & Size Chart

How big does a Border Collie get? What’s the average Border Collie size? When do Border Collies finish growing? If you’re planning to adopt a Border Collie, your mind is probably filled with all sorts of questions. In this Border Collie size guide, we’ll be answering all of them. Let’s dig in!

Our handy interactive puppy growth chart and calculator takes all the hard work out of predicting your puppy’s potential adult size. This helps you to know exactly what you are in for.

Border Collie Size By Age Predictions

Border Collie is an absolute superstar companion. They’re known for their high intelligence levels, work ethic that’s unmatched, and tireless need for exercise and playtime. In the evening, be prepared to cuddle up with your tired little pup after a long day of work and playtime. 

So how big does a Border Collie get? Border Collie is a medium sized breed, but with energy levels so high through the roof, it might make you feel like they’re a lot larger than they actually are. 

Typically, Border Collies can weigh anywhere between 30 to 55 pounds, and stand at 18 to 22 inches tall at the shoulder. Of course, there might be more fluctuation in terms of numbers, but most Border Collies fall into this size range.

In addition, for your Border Collie puppy to grow into a healthy adult dog, we recommend you feed them specially formulated puppy food. Here you can learn more about how much you should feed your Border Collie puppy. 

Are There Different Sizes Of Border Collie?

Now that we know the average Border Collie size, let’s discuss the different sizes of Border Collie. Firstly, your Border Collie’s full-grown size is determined by a variety of factors like their gender, size of their parents, how much they eat, and exercise. Usually, male Border Collies can be slightly larger than females.  

Here’s a Border Collie size chart for males and females:

	Male Border Collie	Female Border Collie
Weight	40-55 pounds	30-45 pounds
Height	19-22 inches	18-21 inches
When Full-Grown?	18 months	18 months

*A dog’s height is measured from their withers, also known as the shoulder blades.

As we can see from the Border Collie size chart above, females tend to weigh slightly less than males. Although both female and male Border Collies are almost the same height, there can be a slight difference of a few inches. 

Moreover, you might have heard about the Toy or Mini Border Collie size. Even though some breeders might advertise their Border Collies as such, please be cautious of any of these promises. Mini Border Collies are usually a result of selective breeding, where runts or puppies with the dwarfism gene are crossed to achieve a certain look. 

However, runts and dogs with the dwarfism gene are at a much higher risk of developing health problems. Therefore, continuously crossing these pups can result in unhealthy new litters. If you’ve decided to opt for adopting a puppy from a breeder instead of a shelter, we recommend you learn more about how to choose a responsible breeder.

In addition to the Border Collie, there are also a few other Collie breeds that might confuse some. Mainly, the Collie and Bearded Collie. The Collie is larger than the Border Collie – typically weighing around 50 to 75 pounds, and standing at 22 to 26 inches tall at the shoulders. The fluffier Bearded Collie is more similar in size to Border Collie. Bearded Collies usually weigh around 45 to 55 pounds, and stand at 20 to 22 inches tall. 

Furthemore, thanks to their similar looks, Border Collies are often mixed up with the Australian Shepherd. They’re both very similar in size, and have an athletic build combined with high energy levels. However, Aussies are around 10 pounds heavier than Border Collies. 

Border Collie Size Charts & Growth Patterns – Month Wise 

When adopting a puppy, it’s important you know what to expect in the upcoming months in terms of their growth and development. All dogs follow similar growth patterns with slight differences. For instance, large and giant sized breeds will typically take around 18 to 24 months to reach their full-grown size, whereas small sized breeds will usually finish growing before their first birthday. 

Let’s have a look at the average Border Collie size chart by age:

Age	3 months	6 months	9 months	12 months	18 months
Weight	8-15 pounds	15-30 pounds	25-40 pounds	30-45 pounds	30-55 pounds
Height	10-12 inches	12-16 inches	15-19 inches	18-22 inches	18-22 inches

As we can see from the Border Collie size chart, these dogs will usually reach half their adult size around 6 months old. After that, a Border Collie puppy’s growth will significantly slow down, until it plateaus around 12 to 18 months old. Meanwhile, by their first birthday, they’ve most likely reached their adult height. 

Additionally, even after reaching their full-grown size around 18 months old, Border Collies might take a few more months to fill out their chest. So, it’s not unusual for a Border Collie to gain a few more pounds up until their second birthday. Especially if they are naturally larger in size. 

How Big Is A Full Grown Border Collie?

Border Collie’s full-grown size usually fits within 30 to 55 pounds in weight, and 18 to 22 inches in height. Female Border Collies tend to run slightly smaller than the male pups. The average female Border Collie usually weighs around 30 to 45 pounds, and stands at 18 to 21 inches tall at the shoulder. Male Border Collie’s full-grown size averages between 40 to 55 pounds, and they stand at 19 to 22 inches tall. 

A different formula you could use is:

1. Growth = current weight / current age in weeks
2. Adult weight = Growth x 52 (number of weeks in one year)

So, for example, if your 12-week old pup weighs 18 pounds. You simply divide the current weight by their age in weeks and multiply the result with 52:

Are Border Collies Medium Or Large Dogs?

Border Collies are medium sized athletic dogs. Although when looking at their size, we could expect them to live comfortably in an apartment. However, Border Collies have very high energy levels and need lots of exercise and playtime daily. Therefore, this pup will do better in a more spacious home and with a family who can spare a few hours a day for proper exercise. 

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We hope our Border Collie size guide has been a helpful resource in understanding the growth and size of this gorgeous pup. After all, it’s important that you’re fully prepared and know what to expect when you bring your new puppy home.