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How Big Do Brittany Spaniels Get? [Average Size Guide]

Brittany Spaniels, or Brittanys depending on where they reside, certainly have their resemblance to other dogs. They behave more like a pointer or a setter, yet the appearance of a spaniel. It comes as no surprise there is much debate surrounding the breed name. But how big does this dog get? What breed does this vibrantly coated dog take after in size? Here is what you need to know.

So, how big do Brittany Spaniels get? Brittany Spaniels typically reach between 17-20″ (43-50 cm) in height and weigh between 30-40 lbs (13-18 kg), on average when fully grown. They generally reach their final size between the ages of 12-16 months, depending on how big they get. Males and females of the breed do not vary much in size.

Brittany Spaniel Size

Brittanys are without a doubt a medium-sized breed. They fit the classification perfectly.

And while they have their similarities with pointers, setters, and the spaniel group, they are unique.

They are smaller in frame and structure than setters but have larger legs than your average spaniel.

What you get is a favorably-sized, sturdy, and enthusiastic dog that was born for an active lifestyle.

This is a breed that will keep you busy.

They simply love being outside and being kept active. Whether physically or mentally.

Let us now take a closer look at the breed’s growth rate in further detail.

This way, you will know exactly what you expect should you decide to bring a young pup home.

We will then move onto what their final size means from an ownership perspective, so be sure to keep reading!

Brittany Spaniel Proportions

Brittany Spaniels are well-built dogs, longed-legged and square in proportion (with height matching the body’s length).

This breed is also known for being light in bone, and adding this to their proportions enables them to be so agile and fast.

So much so that the Brittany is recognized for their ability to move quickly.

They are equally alert and keen to run, should or if given the opportunity.

They can be born tailless or even have it later docked to about 4″ in length.

At What Age Is A Brittany Spaniel Full Grown?

The average Brittany Spaniel will reach their full adult size between 12-16 months, depending on how large they become (with smaller dogs of the breed reaching their final size faster).

Generally, there is little difference in size between males and females.

Nevertheless, let us look at the respective growth rates of Brittany Spaniels for both sexes, from puppy through to maturity.

Growth Of A Male Brittany Spaniel

  • The weight of a male Brittany Spaniel at 3 months should be between 13 and 16 pounds.
  • At 6 months, they will likely weigh between 23 and 30 lbs (pounds).
  • At 1 year, a male Brittany Spaniel should weigh between 30 and 40 lbs (pounds).
AgeWeight – Low Average
Weight – High Average
3 Months1316
4 Months1721
5 Months2025
6 Months2330
7 Months2532
8 Months2633
9 Months2735
10 Months2836
11 Months2937
12 Months3038
13 Months3038
14 Months3039
15 Months3039
16 Months3040

Growth Of A Female Brittany Spaniel

  • The weight of a female Brittany Spaniel at 3 months should be between 13 and 16 lbs (pounds).
  • At 6 months, they will likely weigh between 23 and 30 lbs (pounds).
  • At 1 year, a female Brittany Spaniel should weigh between 30 and 38 lbs (pounds).
AgeWeight – Low Average
Weight – High Average
3 Months1316
4 Months1721
5 Months2025
6 Months2330
7 Months2532
8 Months2633
9 Months2735
10 Months2836
11 Months2937
12 Months3038
13 Months3038
14 Months3039
15 Months3039
16 Months3040

As the data suggests, there is little variance between the breed; the smallest and the largest are not too dissimilar in weight and size.

For instance, the largest male Brittany Spaniel will likely be only 10 pounds heavier compared to the lightest of the breed.

Spatial Requirements Of Brittany Spaniels

Being medium-sized, the Brittany is an appealing breed to own. They are not too large and cumbersome, and they can easily be transported in the car. Being so agile, they are very versatile too.

But, with this breed, you are going to need a bit more space than you might have originally had thought.

These dogs do not suit nor adapt very well to an apartment or small-living quarters.

And this may come as a surprise.

They’re not a huge dog, after all.

But they are certainly energetic ones.

They simply need sufficient space to stay active.

They’re just not going to lay around all day.

Nor should they.

And this means owners need to be willing and able to keep their dog sufficient attention, busy, and active.

Otherwise, they are likely to suffer from hyperactivity, separation anxiety, and other behavioral disorders when left alone for too long with too little to do.

So, a sufficiently large property with access to outdoor space is a must for this breed.

A fenced yard where this dog can roam and play will serve them well.

Failing this the ability to routinely take them outsides for walks, hikes and other activities.

Exercise And Dietary Needs Of Brittany Spaniels

To keep a Brittany Spaniel at a healthy weight and happy in mind, it’s imperative that they are given sufficient exercise and an appropriate diet.

Let us now take a closer look at what this means for this particular breed:


Brittany Spaniels are renowned for their exuberant nature, and as a sporting breed, have quite a lot of energy that needs to be channeled appropriately.

So, it naturally follows that they need plenty of exercise.

1-2 hours per day is considered a minimum.

And this structured exercise should also be broken up over the course of the day, and on top of regular movement and play outside.

Regarding the 1-2 hours, it should include long, somewhat challenging walks (including hikes) and running on a leash.

Some owners even report that they need to run with their Brittany for up to 45 minutes per morning to taper their energy throughout the day.

This appears to be more critical in dogs that are being left at home for some time.

Beyond this, they should be kept mentally stimulated via various games – fetch with a ball is one such way to exercise them in both ways.

Visiting dog parks in the quieter evenings is another useful approach – where a Brittany can be let off the lead to run and explore, yet still, get some socialization with other dogs and people.

Of course, exercise should be given appropriately and per the age of the dog.

Puppy Brittany spaniels should not be over-exercised, and activity should not be too rigorous. It must be appropriately increased, and you must be mindful while they are still growing.

So, it is generally advised to keep running to a minimum in the early months of life.

Although exercise is crucial to healthy muscle development, so should not be too limited, even at a young age, either.


A Brittany needs a high-quality diet. This will ensure optimal growth through the puppy years, while it will support a healthy weight as they age.

Both commercially manufactured and home-prepared food can suffice, although, for the latter, you must ensure that they are getting all the nutrition they need. Consulting with a vet is generally advised.

A Brittanys diet should be fed per their age, weight, and size.

The average adult Brittany should be eating around 1-2 cups of dry dog food per day, fed in the morning and the evening.

Puppies however, will need to eat more frequently, at 3-4 meals per day.

It will also need to be orientated to younger dogs.

Puppy’s need sufficient energy to grow, whereas this excess energy can result in weight gain in older dogs.

Treats do have their place, especially in training this dog, but should not be overdone.

Other Factors That Can Impact Brittany Size

Dogs of the Brittany breed do not generally vary much in size, but there are a few other main factors that can impact how big they ultimately get:


Every breed of dog inherits a lot of its final size potential from the parental breeds; and other dogs in the lineage.

Therefore, to get a better estimate of how big a dog will ultimately get, it is useful to look at the dogs used in breeding.


Injuries can both impact a dog’s ability to stand tall and also their ability to exercise (resulting in potential weight gain if the diet is not tailored accordingly).

For the Brittany breed, they are more susceptible to a condition known as Hip Dysplasia. 

This can be brought upon by genetics, the environment, and even diet.

Nevertheless, it is a deformity of the hip joint. It can cause a lot of pain and mobility issues and may even require surgery.

Health Conditions

Some Brittany spaniels suffer from a condition known as Hypothyroidism (under-active thyroid).

This can result in obesity, lethargy, and several other adverse symptoms (including coat issues and infertility if left untreated).

Hypothyroidism can be treated, but it does require daily medication.

Otherwise, a Brittany can put on and retain excess weight.


The Brittany Spaniel is an athletic, medium-sized dog. They’re not particularly big, nor are they a lapdog either.

They are generally very affectionate, child-friendly, intelligent, playful, and trainable.

That being said, this is not a dog breed for everyone and every family.

They are very energetic.

This must be acknowledged, accepted, and effectively channeled by any owner.

They need a lot of both physical and mental stimulation to remain happy.

And as such, this breed has a lot of enthusiasm for any activity they partake in.

And such energy needs to be matched.

I have even seen one owner describe their Brittany in the following way: “they can fun, run and run some more.”

It epitomizes the nature of this dog in many ways.

So, if you are considering this particular breed, be sure you can commit the time, attention, and effort to train, socialize and exercise with them.

In doing so, you will have a fantastic family companion.

Otherwise, they may be more than you might have bargained for.