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!

Preacher

Mastiff

Male, Young

King City, ON

Size

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

Details

Story

Learn More

Hallie

Mastiff

Female, 2 yrs

Kingston, ON

Size

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

Details

Story

Meet Hallie!Joined us in: June 2026About Hallie:· Weighs 33kg.· A sweet, affectionate girl who enjoys attention and spending time with her people.· Can be nervous when meeting new people but warms up with patience and kindness.· Loves to run and play and would thrive with opportunities to burn off her energy.· Would benefit from basic obedience training and confidence-building exercises.· Highly food motivated, making training a fun and rewarding experience.Her perfect match:· An experienced owner who understands the needs of a strong, energetic dog.· A home with a fenced-in yard or secure outdoor space where she can safely run and play.· Someone committed to continuing her training, including leash manners and basic obedience.· A family with dog-savvy children aged 10 years or older who can interact respectfully with her.· May potentially do well with another dog of a similar size and energy level that can appropriately take correction.Some extra facts about Hallie:· Highly food motivated and should be fed separately from other animals, as she may guard her food.· Can be strong on leash and would benefit from continued leash training.· Enjoys being active and will thrive with regular exercise and enrichment.· Takes a little time to feel comfortable in new situations but forms bonds once she trusts you.· A silly and loyal companion with really great zoomies.In short:Hallie is a sweet, active girl looking for an experienced home that can provide guidance, structure, and continued training. With patience, confidence-building, and plenty of opportunities to exercise and have fun, she has all the makings of a loyal and affectionate companion.

Learn More

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.

Learn More

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.

Learn More

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. Due to time constraints, we cannot respond to every email asking for more information on a dog. Please carefully review the bio for the dog and our adoption process https://www.speakingofdogs.com/adoption/adoption-process/. If you are still interested in adopting, please fill out the adoption application form at the bottom of that page. July 17, 2026, 5:29 pm

Learn More

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

Meet Coops - A Gentle Soul Looking for His Forever Family Coops is a sweet, gentle-hearted young pup with a calm nature and a heart full of love to give. This handsome Mastiff mix was rescued alongside his two brothers after they were found wandering a remote highway in northern Manitoba. Despite his difficult start in life, Coops has shown nothing but kindness, resilience, and a quiet eagerness to trust. At just 7 months old, Coops is still discovering the world around him. He can be shy when meeting new people, but with patience, gentle encouragement, and a loving environment, his confidence continues to grow every day. Having a friendly, well-balanced canine companion in the home would be a huge benefit to this sweet boy, helping him feel safe and learn from a trusted friend. Coops is wonderful with other dogs and absolutely amazing with cats. He also does well with children and has a soft, gentle temperament that makes him a joy to be around. He enjoys car rides, is learning to walk on leash, and approaches life with a playful and inquisitive spirit. Coops has conquered house training and crate training with flying colours. He is not food aggressive, is comfortable being handled, and has shown no leash reactivity toward people or other dogs. Coops would thrive in a home with a secure yard, another friendly dog, and a family committed to helping him continue building his confidence. While he isn't suited to apartment living, he will make a wonderful companion for someone willing to give him the time, patience, and love he deserves. Could Coops be the missing piece your family has been searching for? This sweet, soulful boy is waiting for a patient and loving home where he can continue to blossom into the amazing companion he was always meant to be. 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: Yes Crate trained: Yes Energy level: Medium Can be handled/touched: Yes Flight risk: No Walks on leash: Working on it Leash reactive to people or dogs: No Rides well in car: Learning Food aggressive: No Destructive: Puppy Needs a yard: Yes Needs another dog: Yes 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.

Learn More

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

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

Home

Adopt a Dog

Adopt a Mastiff

Ontario

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