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Mastiff puppies and dogs in Ontario

Looking for a Mastiff puppy or dog in Ontario? Adopt a Pet can help you find an adorable Mastiff near you.

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Adopt a Mastiff near you in Ontario

Below are our newest added Mastiffs available for adoption in Ontario. To see more adoptable Mastiffs in Ontario, use the search tool below to enter specific criteria!
Photo of Tango

Tango

Mastiff

Male, 5 mos
Hamilton, ON
Size
(when grown) Large 61-100 lbs (28-45 kg)
Details
-
Story
Meet Tango — a 4–5-month-old Mastiff/Lab cross puppy with giant paws, a growing personality, and enough charm to bulldoze his way straight into your heart. Tango arrived at the shelter as a “stray,” which honestly feels hard to believe because this sweet boy clearly thinks people are pretty wonderful. Like many puppies, he can be a little shy when meeting new people at first but give him about five minutes and suddenly you’ve got a wiggly best friend following you around like you’ve known each other forever. He’s playful, social, goofy, and currently at that fantastic puppy stage where every single thing in the world is exciting. A leaf blowing across the yard? Incredible. A squeaky toy? Life-changing. Your shoelaces? His greatest enemy. Tango also arrived with Demodex Mange, which he has been treated for and is recovering from nicely. Demodex mange is a common skin condition in puppies caused by microscopic mites that naturally live on dogs’ skin. Young puppies can sometimes develop it when their immune systems are still maturing, leading to hair loss, irritated skin, and scabbing. The good news is that it is treatable, and Tango is already healing well — his scabs are improving, his skin is recovering, and now that he’s starting to feel better, his happy puppy personality is really shining through. This handsome boy already knows “sit,” and he’s eager to learn more. Continued obedience training and crate training will be very important as he grows, especially because Tango is expected to become a large dog. Right now, he may just be an oversized puppy with floppy enthusiasm, but one day he’ll be an oversized adult dog with floppy enthusiasm — so starting his training early will help him become the very best version of himself. As a Mastiff/Lab mix, Tango will need plenty of daily exercise, mental enrichment, and positive guidance to keep both his body and his big puppy brain happy. Puzzle toys, walks, training games, and family adventures will all help this growing boy thrive. Overall, Tango is exactly what many people dream of in a family dog: affectionate, playful, social, and full of potential. He just needs a home willing to put in the time, patience, and training needed to help a young puppy grow into a confident, well-balanced companion. Please complete an adoption application: https://www.hamilton.ca/home-neighbourhood/animals-pets/adopt-or-foster-pet/adoptions Tracker has a future appointment to be neutered once he is fully recovered. His adopters must be willing to return him to a Hamilton clinic for this surgery, which is included in the adoption fee. Animal adoptions and viewing are by appointment only. This allows our Adoption Staff to spend quality time with each potential home to ensure the most successful matches are made between the animals and their new families. *Please note: we only adopt within Ontario
Photo of Thor

Thor

Mastiff/American Bulldog

Male, Adult
Keswick, ON
Size
(when grown) -
Details
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Story
Hello there! My name is Thor, Male - neuteredMastiff x American Bulldog MixApprox. 2 years oldI'm a big, lovable marshmallow wrapped in an even bigger package. My heart is as large as my frame, and I'm eager to share all the love I have with my forever family. I tend to form strong attachments to my favourite individuals, protecting them from unknowns though I am focused on establishing positive boundaries with the help of my shelter friends. When it comes to people, I'm friendly but can get a little nervous, especially around sudden movements. I thrive best with slow and gentle introductions. Once I feel comfortable, I transform into your classic wiggle bug, ready to make friends and soak up all the affection you have to offer.I enjoy my meals at a normal pace, but what really gets my tail wagging is praise, treats, and spending time with people. I'm highly motivated by love and snacks, which makes training and bonding with me a rewarding experience. I can become protective over toys, so I would do best in a trade-off situation or with gradually introduced toys once I'm settled into my new home. Too much excitement too quickly can be overwhelming for me.I'm still working on my basic training, which means we can learn together. With your guidance and a few tasty treats, I'm sure to pick up on commands and become the well-mannered companion you're searching for.Given my energy and size, I would thrive in a quiet home without young children-preferably with kids aged 12 years or older. I can be selective with doggy friends, but with a slow introduction, I may have the potential to socialize successfully. I do have a prey drive towards cats and would require a home without feline friends.If you're looking for a gentle giant who will fill your home with love and laughter, I'm your guy. Primary Color: Black Brindle Secondary Color: Black Brindle Weight: 42.001 Age: 2yrs 0mths 3wks
Photo of Humphrey

Humphrey

Mastiff

Male, 8 mos
Kingston, ON
Size
(when grown) Med. 26-60 lbs (12-27 kg)
Details
Good with kids, Good with dogs,
Story
Hi, I'm Humphrey! I'm a sweet young pup who loves to snuggle and play. You may notice my skin looks a little funky. I'm working closely with my dogter to manage my skin health. I've made great improvements but we're still working on determining the root cause.  MI, Mastiff Mix approx 50lbs EST DOB: Sept 2025
Photo of Noelle

Noelle

Mastiff

Female, 4 yrs 1 mo
London, ON
Size
(when grown) Large 61-100 lbs (28-45 kg)
Details
Good with kids, Not good with dogs, Not good with cats, Needs experienced adopter, House-trained,
Story
Re-introducing Noelle! Noelle Fostered in London, On Vaccinated & Spayed & Microchipped Adoption Fee: $500 Mastiff Mix (our best guess) I come with 30 days of free Pet Insurance Hi, I’m Noelle! I’m about 4 years old, and I’m a Mastiff mix who started life as a stray—but thankfully, I was rescued. I’ve been waiting over a year for my perfect forever home, and I think it’s finally my time to tell the world about myself since I've been introduced last. I love going for walks and car rides, but most of all, I adore my people. I’m happiest right by your side (or on your lap, if you’ll let me!). I’m gentle, affectionate, and wonderful with kids I’ve had more stress in my life than a girl like me deserves, so sometimes I can be a bit reactive. The good news is I’ve made amazing progress with my foster family and my friends at Holy Sit Training. I usually walk really well—especially if you bring treats (hint hint!) I am officially Heartworm negative!! which now allows me to get my zoomies out and make you laugh Every now and then, things like certain dogs, motorcycles, or other wheeled vehicles can make me anxious. When that happens, I might jump around or try to chase, so I’ll need someone strong and confident to help guide me—I’m about 80 lbs, after all! I’m very food-motivated and eager to please, which makes training fun and rewarding. I do have a high prey drive (skunks beware) , and while I’m curious about the resident cat in my foster home, she’s not too interested in being my friend… although we’ve been caught almost snuggling once. I’d love a home with a fenced yard (at least 4 feet—I can leap like a ballerina!). Most importantly, I’m looking for someone patient and experienced who can continue helping me grow with structure and training. In return, you’ll get the most loving, loyal cuddle bug you’ve ever met. I just know my perfect person is out there—could it be you? -Noelle BSDRO Foster Dog XOXO
Photo of Priscilla

Priscilla

Mastiff

Female, 6 yrs 4 mos
Toronto, ON
Size
(when grown) Large 61-100 lbs (28-45 kg)
Details
House-trained,
Story
Meet Priscilla, queen of the dog park! Priscilla is such a cutie and just the sweetest girl. She has a curious spirit, a love for treats and has already shown herself to be an affectionate and eager-to-please dog! She always gets excited to see our volunteers and will greet them with her whole body wagging, eager for some attention and maybe a tasty snack or two. On walks, Priscilla is excited to explore and does well when walked at her pace. While she’s confident enough to explore quieter areas, she can get a little spooked by busy or high-traffic zones, but she settles down quickly once she’s in a calmer environment. She’s a quick learner, and she comes right to you when called, especially if there’s a treat involved. Priscilla really enjoys spending time outside, whether walking, playing or simply people-watching. She just enjoys being in the moment! When it’s time to head back, she’s easy to return back home and will happily go back inside for a good petting session. Priscilla is a friendly and sweet-natured dog who thrives on companionship. She will need a patient family that can continue to build her confidence and help her adjust to her new routine at her own pace. She will soon blossom into the loving, loyal companion she’s meant to be. Come say hi to Priscilla today!
Photo of HK

HK

Mastiff

Male, 6 yrs
Toronto, ON
Size
(when grown) X-Large 101 lbs (46 kg) or more
Details
House-trained,
Story
HK is a big, goofy 100-pound sweetheart who truly believes he’s a lap dog! This gentle giant has a heart as big as his paws and is always ready to make you smile with his silly antics and affectionate personality. HK loves spending time with his people — he’ll lean right in for cuddles and happily soak up all the love you have to offer. HK’s favorite things? Treats, exploring new places, and being your #1 sidekick. He enjoys going for walks and exploring the world, though due to his size and strength, he’ll need someone comfortable handling a large dog. HK is currently working on his leash manners and learning to stay calm when he spots other dogs. With ongoing positive reinforcement training, he’s making great progress and showing that he’s eager to learn! If you’re looking for a loyal, loving best friend who’ll fill your life with laughter (and maybe take up a bit of space on the couch), HK is your guy!

Search for a Mastiff puppy or dog

Use the search tool below to browse adoptable Mastiff puppies and adults Mastiff in Ontario.

Mastiff puppies and dogs in Ontario cities

Mastiff Puppies near me Mastiff in Acton Mastiff in Alliston Mastiff in Almonte Mastiff in Amherstburg Mastiff in Angus Mastiff in Arnprior Mastiff in Aylmer Mastiff in Ayr Mastiff in Azilda Mastiff in Barrie Mastiff in Beamsville Mastiff in Beeton Mastiff in Belleville Mastiff in Binbrook Mastiff in Blenheim Mastiff in Bobcaygeon Mastiff in Bolton Mastiff in Bowmanville Mastiff in Bracebridge Mastiff in Bradford Mastiff in Brantford Mastiff in Brighton Mastiff in Brockville Mastiff in Caledon East Mastiff in Caledonia Mastiff in Campbellford Mastiff in Carleton Place Mastiff in Casselman Mastiff in Chatham Mastiff in Chelmsford Mastiff in Clinton Mastiff in Cobourg Mastiff in Cochrane Mastiff in Collingwood Mastiff in Cornwall Mastiff in Corunna Mastiff in Crystal Beach Mastiff in Deep River Mastiff in Delhi Mastiff in Dorchester Mastiff in Dryden Mastiff in Dunnville Mastiff in Elliot Lake Mastiff in Elmira Mastiff in Embrun Mastiff in Espanola Mastiff in Essex Mastiff in Exeter Mastiff in Fergus Mastiff in Fort Erie Mastiff in Fort Frances Mastiff in Gananoque Mastiff in Georgetown Mastiff in Goderich Mastiff in Gravenhurst Mastiff in Guelph Mastiff in Haileybury Mastiff in Hamilton Mastiff in Hanover Mastiff in Hawkesbury Mastiff in Hearst Mastiff in Huntsville Mastiff in Ingersoll Mastiff in Innisfil Mastiff in Iroquois Falls Mastiff in Kanata Mastiff in Kapuskasing Mastiff in Kemptville Mastiff in Kenora Mastiff in Keswick Mastiff in Kincardine Mastiff in King Mastiff in Kingston Mastiff in Kirkland Lake Mastiff in Kitchener Mastiff in Leamington Mastiff in Lindsay Mastiff in Listowel Mastiff in Lively Mastiff in London Mastiff in Manotick Mastiff in Marathon Mastiff in Meaford Mastiff in Midland Mastiff in Milton Mastiff in Mitchell Mastiff in Mount Albert Mastiff in Mount Forest Mastiff in Napanee Mastiff in Newcastle Mastiff in New Hamburg Mastiff in New Liskeard Mastiff in Niagara Falls Mastiff in Nobleton Mastiff in North Bay Mastiff in Orangeville Mastiff in Orillia Mastiff in Oshawa Mastiff in Ottawa Mastiff in Owen Sound Mastiff in Paris Mastiff in Parry Sound Mastiff in Pembroke Mastiff in Perth Mastiff in Petawawa Mastiff in Peterborough Mastiff in Petrolia Mastiff in Picton Mastiff in Port Colborne Mastiff in Port Dover Mastiff in Port Elgin Mastiff in Port Hope Mastiff in Port Perry Mastiff in Prescott Mastiff in Renfrew Mastiff in Richmond Mastiff in Ridgetown Mastiff in Rockland Mastiff in Rockwood Mastiff in Russell Mastiff in Sarnia Mastiff in Sault Ste. Marie Mastiff in Shelburne Mastiff in Simcoe Mastiff in Smiths Falls Mastiff in Smithville Mastiff in Southampton Mastiff in Stayner Mastiff in St Catharines Mastiff in St George Mastiff in St Marys Mastiff in Stouffville Mastiff in Stratford Mastiff in Strathroy Mastiff in St Thomas Mastiff in Sturgeon Falls Mastiff in Sudbury Mastiff in Sutton West Mastiff in Tavistock Mastiff in Thunder Bay Mastiff in Tilbury Mastiff in Tillsonburg Mastiff in Timmins Mastiff in Toronto Mastiff in Tottenham Mastiff in Uxbridge Mastiff in Vineland Mastiff in Walkerton Mastiff in Wallaceburg Mastiff in Wasaga Beach Mastiff in Waterford Mastiff in Welland Mastiff in Wellesley Mastiff in Windsor Mastiff in Woodstock

Mastiff shelters & rescues in Ontario

There are animal shelters and rescues that focus specifically on finding great homes for Mastiff puppies in Ontario. Browse these Mastiff rescues and shelters below.

Here are a few organizations

Rescue

Nakoma Rescue

Addison , ON K0E 1A0

Pet Types: dogs

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Shelter

Pawsitive Days Ahead

33 Railway Street, Kingston , ON K7K 2L7

Pet Types: dogs

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Looking for a specific shelter or rescue?

If you're not seeing what you're looking for, try our shelter and rescue search. We have more than 17,000 organizations in our database with furry pals waiting for a new home!

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Want to learn more about adopting a Mastiff puppy or dog ?

We've got all the info you need on adopting and caring for a Mastiff puppy . Check out the links below for everything you ever wanted to know about Mastiff puppies and adults .

Mastiff information

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Where do Mastiffs come from? How many types of Mastiffs are there? From the history of the breed to question about average height, weight and size, brush up on these basic facts about the Mastiff.

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