Breeds Category IconBreeds

Boxer Mastiff Mix: Boxmas Breed Information, Size, Puppies & More

Emma Braby

Last Updated: March 24, 2020 | 8 min read

Boxer Mastiff Mix - Boxmas

Here we are going to discover the mixed designer breed, the Boxer Mastiff mix, also commonly known as the ‘Boxmas’. This pooch is not yet recognized by the American Kennel Club as it is relatively new on the dog scene, but he is already proving to be quite popular.

Boxers are favorites of many people in the United States, and the Mastiff is also a favorite – being the gentle giants that they are.  The mastiff is used in other mixed breeds because of their even temperament and patience with children.

The Boxer is also popular when mixed with a lab, bringing the friendliness and goofiness that the lab is known for to the Boxer breed for a great designer dog. So, without further ado, let’s dive straight into the details of the Boxmas!


As the Boxmas is relatively new his history is not that well documented, his year of origin isn’t officially documented either. Both the Boxer and the English Mastiff originates from Europe, but it is believed that the Boxmas hybrid itself originates from the United States of America, although this is contested by some who believe it was actually Europe, so who really knows!

The Boxer was established in Germany in 1895 and is thought to have been bred from the now extinct Bullenbeisser. The Bullenbeisser was a powerful and larger dog used to hunt bull and wild boar, in English this literally translates to “Bull Biter”. The Germans recognised his powerful and great guarding abilities but wanted him to be more agile and slender in frame.

The Boxer as we know him today is strong with an innate work ethic, he is intelligent and loyal, as well as loving and is known to have a silly streak! The Boxer currently ranks as the 12th most popular dog breed in America according to the American Kennel Club. It is thought that the Boxer is named due to the way in which he uses his front limbs to play and defend himself, almost like a boxer does.

The English Mastiff, originated from England and is one of the oldest known dog breeds. Julias Caesar described the Mastiff during the invasion of Britain in 55 B.C. as impressive defenders of the land who fought alongside their masters. Julias Caesar took specimens of the English Mastiff back to Rome and used them as gladiators to fight against men, lions and other beasts in the arena.

The English Mastiff is more friendly and docile than his ancestors, but he is still courageous and protective of his family and their estate. Similar to and often compared to the Bullmastiff, the English Mastiff is a loving gentle giant and is a great family companion despite their appearance. The English Mastiff is known for being a couch potato and loves nothing more than cuddles on the sofa with his master’s, be warned though, he isn’t bothered that he is the largest dog in the world, and if he fits he sits!

Appearance and Grooming

The Boxmas stands tall and can grow up to 30 inches. His paws look particularly huge when he is born, and he eventually grows into them (kind of!) He is muscular and stocky, and weighs anything between 70 to 100 pounds. As they are relatively new on the scene the difference between the male and the female hasn’t been observed and studied to provide a detailed description yet, but generally the females are at the lower end of the scale with the males at the higher end.

His coat is short, dense and water resistant, and can come in brown, black, or brindle colours with streaks of white throughout his body. The Boxmas is described as a high shedder, this means that you will have to groom your pooch daily. He has short length hair that is very thick and dense and will stick to absolutely everything in your home, but as the saying goes, no outfit is complete without a little dog hair! Daily brushing not only keeps his hair and skin healthy, but it also removes any dead hair cells and promotes blood circulation.

It is important to note that with any mixed breed he can take on either of his parent’s appearances, but typically the pup is known to have the Mastiff frame with the Boxer face.


The Boxmas’ parents both have an impressive history, full of fighting and guarding tales, but more recently known to make great family pets who are a little more affectionate and loving than their ancestors. Both of his parents are similar in their nature and this is perhaps why they make such a great pup!

The Boxmas is energetic and fun-loving and he is known to be playful and dopey at times. He is quite the performer and he will provide hours of endless entertainment for you and your whole family. From falling over his large paws to bouncing around on the family trampoline, he is the class clown, and everyone will love him!

When he is not playing, he will be on guard duty and although he is not overly barky, he will alert you when he thinks it is necessary. Once he learns who his is welcome on his estate and who is not, he will be very loving and playful with all who has his master’s approval!

Due to his protective, but patient nature, the Boxmas has a reputation for being great with children and is popular with family households. If you are lucky enough to tire this guy out for a bit, he is very loving, and you will see the affectionate side that he inherited from his Mastiff parent.


The Boxmas is energetic and exuberant, and therefore he needs high levels of exercise, and if you can’t provide him with this then the Boxmas is probably not for you. He will need at least 60 minutes of exercise a day, otherwise he will become bored and destructive very quickly. As well as general exercise he will also need high intensity playtime and interaction with his humans, such as playing frisbee or visiting dog agility courses, for him to expel all that steam. Maybe you could even try his paw at a bit of boxing! His English Mastiff parent maybe a bit of a couch potato, but this lil’ Boxmas pupper certainly is not!

On top of his exercise, because he is an intelligent dog, he will also need mental stimulation during his ‘down time’. Puzzle toys with treats in them are great for mental stimulation and will keep him entertained for ages. He will also enjoy patrolling his yard and could stand on point for hours, so allow him this and he will greatly appreciate it.

Due to their large size it is important not to over-exercise your pup at a young age as it will place strain on his rapidly growing joints. It is also important to ensure that he does not jump from any height, such as off the bed or a garden wall as he is also susceptible to injury.


This big boy needs around 4 cups of food a day, which is a more significant amount of food than you’d feed a normal purebred boxer. Be careful though, he will eat as much as he can find so keep the food under lock and key! Keep treats to a minimum when they are not being used for training, as at 100 pounds, the extra weight is something this dude and his joints could do without!

Good quality food is the key to keeping your pooch healthy, both for when he is growing and in later life. A low calcium and calorific diet are important to help prevent the health issues described in the next paragraph.


As this guy is a mixed breed, he can inherit health problems from either parent, however, the Boxmas appears to be another generally healthy dog. Here is a list of health issues to look out for in the Boxmas:

Hip Dysplasia: This is an abnormality with the joints and can eventually cause crippling lameness in the limbs and painful arthritis, particularly in larger dogs. As with both his parents, this can be a common problem in later life for the Boxmas. A low calcium diet which is low in calories are one of the preventative measures that can be taken to lower the chances of hip dysplasia from a young age, as well as not over-exercising your pup as discussed earlier.

Gastric Torsion: Gastric Torsion, put simply, is bloat. This occurs when the stomach is enlarged with either air or gas, and then twists. The twisting usually occurs when he eats one large meal a day or eats quickly either before or after intense exercise. Symptoms can include retching without throwing up, excessive drooling, or a rapid heart rate to name but a few. If your pooch displays any of these symptoms, then you need to get him to the Veterinarian immediately as it can be a life-threatening condition.

Brachycephaly: This is a descriptive term for flat-faced dogs, and the Boxmas will likely inherit this from his Boxer parent. This can cause many issues, such as breathing difficulties, dental problems, and heat and heart related issues to name but a few. Be sure to conduct your own research on this for an extensive list of problems and symptoms, as it is likely this condition will affect the Boxmas and you will need to know how to regulate it.

As with any puppy the best way to gain an understanding into his future health is to look at his parents. When you visit the breeder ask them for health certificates of the parents, as well as ensuring that you get to meet both the parents and the pup himself. Ensure that they are all healthy and well looked after, and that their environment is clean and safe. You can expect to pay around $800 for a Boxmas puppy from a reputable breeder.

Remember that regular visits to the Veterinarians and keeping up to date with vaccines will assist in keeping your pup fit and healthy. The Boxmas’ life span is estimated at 10 – 13 years.


Due to his parent’s shared guarding and protective traits it is important that the Boxmas is socialised from a young age. Socialisation is the process of exposing your pup to a range of situations to ensure that he is confident in his environment, both in the home and outside. This can be achieved by taking your puppy to training classes and going to playdates with other dogs of all shapes and sizes. The key is to ensure that each new experience is positive, and to praise him accordingly.

In particular to the Boxmas, because of his protective nature, it is important for him to regularly interact with humans and animals outside of the family unit so that they aren’t over-protective or aggressive. Ensure that the Boxmas pup doesn’t become attached to one family member in particular, as this can create over-protectiveness and hostility within the household. To ensure that your pooch is well-behaved the training needs to be consistent and continued even once the behaviours are learned.

As he is an intelligent dog and he continuously seeks praise from his master, he is relatively easy to train. Be sure to make the training sessions short and fun, though, as he can get bored and distracted easily.

Final Thoughts

This excitable but loving dog will make heads turn for all the right reasons! He can be intimidating in appearance if you don’t know the breed, but for those that do know him will also know that he is a fun and sweet-natured boy.

He is energetic and will require constant stimulation; he rarely has a down-time mode and you must be prepared for this. He will take the role of family guardian seriously and will earn his keep by protecting you at all times. When he is not on guard he will want to play, and boy does this dude know how to play! Energetic playtime such as tug-of-war, frisbee, or doggy agility courses can burn up that energy, and the use of puzzle treat toys will be much appreciated by him when he must be left alone.

Be sure to train him as he is of working and guard dog heritage, as you will want to train the over-protective or aggressiveness trait out of him from a very early age. Once he is transformed into a well-mannered young pup the rewards for both you and him will be endless!

Leave a Comment


Diane Drugge

April 5, 2020 at 2:06 pm

Although our "boxer",brindle, male, was identified as a boxer. his huge size (112 pounds) and taller and broader than I have ever known through many, many years of boxers, it was in my reflection after an untimely death ( an intestinal obstruction, an operation, and Calvin never survived, 2 months shy of seven years) that I discovered that he probably was a Boxmas with a Boxer's docked tail. It's difficult to live without him. I have had boxers since the age of 12.

Although I have had and loved both sexes, I think now, with the current members who miss Calvin, a "serious" French bulldog, who never knew life without the big bro, and Essie, a small silly yappy pug, half the big boys' age, I should bring in a girl, a mature girl who will have the good sense to know what is going on, and have the kooky approach to life that we all share I am now an elderly woman, yet able to take brisk walks around nine acre land as my son and his family are with us on this land.

We have many different animals. Calvin, our big Brindle, lived with 2 cats, 20 chickens, a keet, 3 goats, 3 Swedish ducks, 2 very old horses, and 2 caged exotic birds inside our house. The grandchildren are all in their teens. The adults in my house are my daughter, her husband , my husband and me. We all share in the love and care of our dogs. So, is there a sweet mature dog who will accepts us?

Kelly Wilson

April 5, 2020 at 3:23 pm

Hi Diane! At an older age, we always recommend a smaller dog, so a French Bulldog would be a great pick. If you are looking for a mature dog, you can always check your local rescue and see if they have an option to foster a dog before you fully adopt. Good luck!

Dennis Lynch

April 26, 2020 at 9:54 pm

This is great information. I have a Boxane (Boxer/Great Dane) and considering adopting a Boxmas. Sounds like they will get along swimmingly as they have similar personalities.

Kelly Wilson

April 26, 2020 at 11:00 pm

We always encourage the addition of a new family member when appropriate! Thanks for the comment and good luck with the Boxmas Dennis!

Jeff Blackburn

August 28, 2020 at 7:50 pm

My Boxmas is about 135lbs. Looks the same as the pictures but not as dark.

Kelly Wilson

August 31, 2020 at 2:02 pm

Thanks for commenting Jeff! That's a good-sized Boxmas!