Mastiff Adoption in Ontario: Mastiff Puppies for Sale in Ontario

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!

Spotty Dotty (20260625-05)

Mastiff/Mixed Breed (Medium)

Female, Adult

Niagara Falls, ON

Size

(when grown) Large 61-100 lbs (28-45 kg)

Details

Good with kids, Good with dogs,

Story

Meet Spotty Dotty! Spotty Dotty's story began with heartbreak, but her future is filled with hope. Found abandoned in Northern Manitoba, Spotty Dotty spent weeks waiting faithfully for her owners to return. Sadly, no one ever came back for her. By the time caring neighbours found her, she was severely underweight and starving, yet she never lost her gentle spirit. Since arriving in foster care, Spotty Dotty has flourished. She has settled beautifully into her foster home, adores her foster dog siblings, and has shown everyone what a truly special dog she is. Despite everything she has endured, she remains incredibly affectionate, loving, and trusting. Spotty Dotty is a cuddle enthusiast who loves being close to her people. She has a calm and gentle demeanor that is remarkable for a dog her age and makes her a wonderful companion for a family looking for a loyal best friend. Her sweet nature, kind heart, and quiet resilience shine through in everything she does. Having experienced more hardship than any dog should, Spotty Dotty deserves a family who will cherish her and show her the love she has always deserved. In return, she will reward you with unwavering loyalty, endless affection, and a lifetime of companionship. You won't regret opening your heart to Spotty Dotty. She is truly a treasure-a gentle, loving soul who is ready to spend the rest of her life knowing she is safe, wanted, and loved. Medical notes: Extremely thin Crate size recommended: XL Good with women: yes Good with men: yes Good with kids: yes Good with other dogs: yes Good with cats: untested House trained: yes Crate trained: yes Energy level: medium Can be handled/touched: yes Barker: no Flight risk: no; however all dogs should be considered flight risks in new environments Food aggressive: no Current food: kibble Walks on leash: yes Leash reactive to people or dogs: no Rides well in car: unknown Destructive: no Needs a home with a yard: yes Needs a home with another dog: not necessarily but likes other dogs Can live in an apartment: no Please visit our website niagaradogrescue.com to learn more about this amazing pet and to see other available dogs.

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Mister Parker (20260617-05)

Mastiff/Labrador Retriever

Male, Young

Niagara Falls, ON

Size

(when grown) Large 61-100 lbs (28-45 kg)

Details

Good with dogs, Good with cats,

Story

Are you looking for the one that melts your heart and your feet warm. Look no further than Mister Parker. How can you resist that face with his slightly crossed eye...he is imperfectly perfect! Mister Parker is currently is in a foster home with four other dogs and a cat so having some fur buddies in the home would make him more comfortable. He is a bit of a couch potato who also likes to weigh down your bed blankets. He is the best at couch naps because most times he is snoring with his eyes open. He walks well on a leash, navigates stairs without issues and is crated at times and just settles in and curls up. Mister Parker would do best in a home with older children as he doesn't see well and has some vision impairment. Because of this, making noise before entering rooms or approaching him is important so as not to startle him. Mister Parker likes to feel safe and secure so a calmer home is preferred. Hearing words of encouragement make him relax and enjoy life to the fullest. He definitely loves being outside and dinner time! Good with adults: Yes Good with Kids: Yes, older preferred due to vision impairment Good with dogs: Yes Good with cats: Yes House trained: Yes, once he understands where to go Crate trained: Yes Energy level: Low Can be handled/touched: Yes Flight risk: No; however, all dogs should be considered flight risks in new environments Food aggressive: No Walks on leash: Yes Leash reactive to people or dogs: No Rides well in car: Yes Destructive: No Needs a yard: Yes Needs another dog: No, but preferred due to vision impairment Can live in an apartment: No Please visit our website niagaradogrescue.com to learn more about this amazing pet and to see other available dogs.

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India

Mastiff/Rottweiler

Female, Adult

Toronto, ON

Size

(when grown) X-Large 101 lbs (46 kg) or more

Details

Good with kids, House-trained,

Story

India Rottweiler/Boxer/Dogo Argentino mix (short coat) Large Adult Female This gorgeous brindle gal is India a 4 year old, 100 pound mixed breed dog who will be up to date on her veterinary care and spayed prior to adoption. Her current family is not able to provide her with the time or care she deserves. India is housetrained and crate trained, although, a crate has not been used in the past year or so. She is used to living in an apartment and is said to be quiet and comfortable being left alone while her family works full-time hours. She may whine initially when left in a new environment. She enjoys daily walks for exercise and to do her business. India is a Mastiff mix, and as such, will most likely become very attached to her family members but may initially be a bit wary of new people and animals. She warms up to women more quickly than men. India is currently living with 2 toddlers and is good with them. India has very limited experience with other dogs and has not lived with another dog. She has a Husky friend she likes to interact with on leash. She may react to other dogs when on leash walks who are as far away as on the other side of the street and needs a strong and confident owner to help her work through this behaviour using positive reinforcement based methods. She has also never lived with a cat. Her family is able to bathe and brush her and she has been professionally groomed. Her regular groomer says she is good for grooms. At the veterinarian, she is muzzled for invasive handling. Muzzles can be a great tool to help dog handlers feel safe. If you are looking for a loyal, large breed dog to snuggle with on the couch and believe you can provide India with the care she deserves, please fill out the Adoption Application on our website. June 26, 2026, 11:34 pm

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Coops (20260615-04)

Mastiff/Mixed Breed (Medium)

Male, Young

Niagara Falls, ON

Size

(when grown) Med. 26-60 lbs (12-27 kg)

Details

Good with kids, Good with dogs, Good with cats,

Story

Coops is a sweet, gentle pup with a calm nature and a heart full of potential. He was rescued alongside his two brothers after being found wandering a lonely remote highway in northern Manitoba, and is now looking for a patient and loving family to help him continue building his confidence. He can be shy when meeting new people, but with kindness, encouragement, and ideally a friendly, well-balanced dog companion, he blossoms more each day. He is wonderful with other dogs, amazing with cats, and is doing well learning to walk on leash. Like any pup, he is still working on his crate and house-training skills, but he is eager to learn and has shown nothing but a sweet, gentle temperament. Could Coops be the missing piece in your family? Good with Men: Yes, shy at first Good with Women: Yes, shy at first Good with Kids: Yes Good with dogs: Yes Good with cats: Yes Housetrained: Working on it Crate trained: Working on it Energy level: Medium Can be handled/touched: Yes Flight risk: No; however, all dogs should be considered flight risks in new environments Walks on leash: Yes, needs training Leash reactive to people or dogs: No Rides well in car: Yes Food aggressive: No Destructive: Puppy Needs a yard: Yes Needs another dog: No Can live in an apartment: No Please visit our website niagaradogrescue.com to learn more about this amazing pet and to see other available dogs.

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Blaze (20260615-05)

Mastiff/Mixed Breed (Medium)

Male, Young

Niagara Falls, ON

Size

(when grown) Med. 26-60 lbs (12-27 kg)

Details

Good with kids, Good with dogs, Good with cats,

Story

Blaze is a sweet, gentle pup with a calm nature and a heart full of potential. Rescued alongside his two brothers after being found wandering a lonely remote highway in northern Manitoba, he is now looking for a patient and loving family to help him continue building his confidence. Blaze can be shy when meeting new people, but with kindness, encouragement, and ideally a friendly, well-balanced dog companion, he blossoms more each day. He is wonderful with other dogs, gentle with cats, and is doing well learning to walk on leash. Like any pup, he is still working on his crate and house-training skills, but he is eager to learn and has shown nothing but a sweet, gentle temperament. Could Blaze be the missing piece in your family? Good with Men: Yes, shy at first Good with Women: Yes, shy at first Good with Kids: Yes Good with dogs: Yes Good with cats: Yes Housetrained: Working on it Crate trained: Working on it Energy level: Medium Can be handled/touched: Yes Flight risk: No; however, all dogs should be considered flight risks in new environments Walks on leash: Yes, needs training Leash reactive to people or dogs: No Rides well in car: Yes Food aggressive: No Destructive: Puppy Needs a yard: Yes Needs another dog: No Can live in an apartment: No Please visit our website niagaradogrescue.com to learn more about this amazing pet and to see other available dogs.

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Chico

Mastiff/Mixed Breed (Large)

Male, 3 yrs 5 mos

Bancroft, ON

Size

(when grown) Large 61-100 lbs (28-45 kg)

Details

Good with kids, Good with dogs, House-trained,

Story

🚨 URGENT: CHICO NEEDS A HOME ASAP 🚨 Meet Chico — a 3.5-year-old Mastiff mix weighing about 90 lbs of pure love. Chico is everything you could want in a companion: ✔️ Great with people, kids, and other dogs ✔️ Extremely laid-back and well-behaved ✔️ Walks beautifully on leash ✔️ Crate trained ✔️ Excellent recall ✔️ Neutered, microchipped, and up to date on vaccinations (last vet visit May 25/26) This big, gentle boy is incredibly affectionate and lives for attention. He’s the kind of dog who just wants to be near his people and soak up all the love he can get. 💔 Why is Chico urgent? Due to serious personal health issues, his current owner can no longer care for him. Unfortunately, we do not have space to take him in, making this situation time-sensitive. To help Chico find a home quickly, his adoption fee has been reduced. 🏡 Chico is ready right now for a new family who will love him as much as he loves them. If you’ve been thinking about adding a loyal, gentle giant to your life—this is your sign. 📩 Please reach out ASAP for an application or more information. Let’s find Chico the safe, loving home he deserves. ❤️Ask for application

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Mastiff puppies and dogs in Ontario

Jump to:

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!

Search for a Mastiff puppy or dog

Mastiff puppies and dogs in Ontario cities

Mastiff shelters & rescues in Ontario

Looking for a specific shelter or rescue?

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

Mastiff information

Mastiff basics