Bullmastiff vs Flat-Coated Retriever
A side-by-side comparison to help you find the right breed for your lifestyle.
Bullmastiff
The Bullmastiff is a large, powerful, and loyal breed known for its protective nature and gentle temperament. Originally bred in England as a gamekeeper's companion to guard estates, this breed combines the strength of a Mastiff with the agility of a Bulldog.
Extra Large
Medium
7-9 years yrs
N/A
Flat-Coated Retriever
Also known as: Flattie, Flat-Coat
The Flat-Coated Retriever is a cheerful and energetic gun dog breed known for its glossy black or liver-colored coat and friendly disposition. Originally developed in the UK for retrieving game both on land and in water, this versatile and intelligent breed is celebrated for its playful nature and strong bond with families. Often called the 'Peter Pan' of dogs, they retain their puppy-like enthusiasm well into old age.
Large
High
9-12 yrs
56-62 cm
25-36 kg
Quick Comparison
| Trait | Bullmastiff | Flat-Coated Retriever |
|---|---|---|
| Energy | ||
| Trainability | ||
| Grooming Needs | ||
| Family Friendly | ||
| Independence |
Key Characteristics
| Good with Kids | ||
| Good with Dogs | ||
| Good with Cats | ||
| Hypoallergenic | ||
| Apartment Friendly | ||
| First-Time Owner OK |
| Detail | Bullmastiff | Flat-Coated Retriever |
|---|---|---|
| Size | Extra Large | Large |
| Energy Level | Medium | High |
| Grooming | Medium | Medium |
| Trainability | challenging | Moderate |
| Barking Level | Low | Medium |
| Shedding Level | Medium | High |
| Chew strength | Hard | Hard |
| Housing | Yard | Yard |
Owner Fit & Decision Guide
Owner Match
| Trait | Bullmastiff | Flat-Coated Retriever |
|---|---|---|
| Experience Level | Experienced | Intermediate |
| First-Time Owner | ||
| Ideal Owner | Active individual or family who can provide adequate exercise and training for a Bullmastiff. | Active family with a yard who wants a permanent puppy and can handle potential health heartbreak. Works from home or can provide midday breaks. |
Bullmastiff Dealbreakers
- Cannot meet 60-60 min daily exercise
- Cannot commit to grooming needs
Flat-Coated Retriever Dealbreakers
- Sedentary lifestyle - will become a nightmare without daily exercise
- Fastidious cleanliness - they shed, track mud, and drool water
- Emotional fragility - sensitive dogs that become anxious with anger/shouting
- Work long hours away from home
- Not financially prepared for cancer treatment
Surrender Risk
| Factor | Bullmastiff | Flat-Coated Retriever |
|---|---|---|
| Risk Level | Medium | Low to Medium |
| Primary Reasons | Underestimated exercise needs, Behavioral challenges, Cost of care | Energy mismatch - owner underestimated exercise needs, Separation anxiety - owner works too much, Slow maturation - puppy brain in adult body for 2-3 years |
Temperament & Personality
Behavior Comparison
| Trait | Bullmastiff | Flat-Coated Retriever |
|---|---|---|
| Prey Drive | ||
| Watchdog Ability | ||
| Stranger Friendly | ||
| Drool Level | ||
| Wanderlust |
Vocalization
| Trait | Bullmastiff | Flat-Coated Retriever |
|---|---|---|
| Barking Level | Low | Medium |
| Howling Tendency | ||
| Whining Tendency | Low | High |
| Separation Vocalization |
Safety & Reliability
| Trait | Bullmastiff | Flat-Coated Retriever |
|---|---|---|
| Escape Artist | ||
| Dog Park Suitable | ||
| Off-Leash Reliable | ||
| Small Animal Safe | ||
| Leash Reactivity | ||
| Resource Guarding Risk | Low | Low |
Bullmastiff Social Traits
Moderate
Selective
Flat-Coated Retriever Social Traits
None
Loves all dogs - same-sex aggression is rare
Training
Bullmastiff
- ** Positive reinforcement is the only viable path. Harsh corrections often cause this breed to shut down or become defensive.
Flat-Coated Retriever
- Use high-value food rewards - they are highly food-motivated
- Keep training sessions fun and playful
- Harsh correction causes shutdown or passive 'noodle-like' behavior
- Channel retrieval instinct into carrying tasks
Bullmastiff Considerations
This is a genetically rooted trait in many Bullmastiffs. While they may coexist peacefully with dogs of the opposite sex, placing two males or two females together often results in severe conflict once they reach social maturity (18–24 months). This aggression is rarely "cured" through training; it is managed.
Bred to track and hold poachers silently without human direction, the Bullmastiff is an independent problem solver. They do not have the "will to please" of a Golden Retriever. If a command does not make sense to them, they will simply ignore it. This is often misinterpreted as stupidity; it is actually a refusal to perform rote tasks without high-value motivation.
While independent in thought, they are physically clingy. They will lean their 120-pound bodies against you, sit on your feet, and follow you from room to room. This constant physical presence can be overwhelming for owners who value personal space.
Flat-Coated Retriever Considerations
Unlike Golden Retrievers that settle around age 2-3, Flat-Coats retain high-octane, boisterous puppy energy well into their senior years (7+). Exuberant jumping and face-licking can be dangerous for small children or frail elderly owners.
This is a true 'velcro' breed with very low tolerance for isolation. Leaving a Flat-Coat alone for 8+ hours often results in severe destruction (chewing drywall, digging carpets) and distress vocalization.
Approximately 54% of Flat-Coated Retrievers die from cancer, with Histiocytic Sarcoma affecting up to 20% of the breed. Average diagnosis age is tragically young (8-9 years).
As a retriever, their solution to excitement is to grab something with their mouth. If a toy isn't available, they will grab your arm, sleeve, or pant leg. This 'soft mouth' hold requires consistent redirection training.
Multi-Species Compatibility
| Species | Bullmastiff | Flat-Coated Retriever |
|---|---|---|
| With Cats | Generally safe with proper introduction | Usually good if raised together, though may try to play (which cats may not appreciate) |
| Small Mammals | Supervision required | Moderate risk - supervision required |
| Birds / Reptiles | Caution advised | High risk - they are bird dogs, flying birds trigger hardwired response |
Advanced Behavior
| Trait | Bullmastiff | Flat-Coated Retriever |
|---|---|---|
| Predatory Sequence Risk | Medium | Arrested |
| Biddability | Low | High |
| Noise Sensitivity | Low | Low |
| Territorial Barking | ||
| Same-Sex Aggression Onset | 18 months | N/A |
Flat-Coated Retriever: Eye -> Stalk -> Chase -> Grab (Soft). Kill/Dissect bred out to preserve game birds. Safe with poultry if trained. High biddability but add their own 'flair' to commands.
First Year & Life Stages
First Year Challenges
| Challenge | Bullmastiff | Flat-Coated Retriever |
|---|---|---|
| Puppy Difficulty | ||
| Destructive Phase | 6-18 | 6-18 |
| House Training | Moderate | Moderate |
| Crate Training | Medium | High |
| Adolescent Regression |
Bullmastiff: Bullmastiff puppies require consistent training and patience.
Flat-Coated Retriever: Scores higher than Golden Retriever (6/10) due to slower maturation - essentially a puppy brain in a large, powerful adult body for 2-3 years. 'Happy peeing' when greeting is common.
Life Stages Timeline
| Stage | Bullmastiff | Flat-Coated Retriever |
|---|---|---|
| Puppy Phase | 12 months | 18 months |
| Adolescence | 6-18 | 6-36 |
| Adult Years | 2-8 | 3-7 |
| Senior Onset | ~8 years | ~8 years |
| Peak Energy Age | 1-3 years | 1-5 years |
Size & Physical Characteristics
Physical Stats
| Measurement | Bullmastiff | Flat-Coated Retriever |
|---|---|---|
| Height | N/A | 56-62 cm |
| Weight | Not enough data yet | Not enough data yet |
| Size Category | Extra Large | Large |
| Lifespan | 7–9 years | 9–12 years |
| Litter Size | 4-8 | 4-8 |
Bullmastiff Coat
Flat-Coated Retriever Coat
Lineage & Origin
| Detail | Bullmastiff | Flat-Coated Retriever |
|---|---|---|
| Original Purpose | Developed in mid-19th century England, the Bullmastiff was created by gamekeepers to combat poachers | Retrieving shot game (pheasant, duck) from both land and water |
| Origin | N/A | United Kingdom, mid-19th century |
Breeding Details
| Detail | Bullmastiff | Flat-Coated Retriever |
|---|---|---|
| C-Section Rate | Varies | Low |
| Whelping Difficulty | Medium | Low |
| Puppy Mortality Rate | Low | Low |
Physical Risks
| Risk | Bullmastiff | Flat-Coated Retriever |
|---|---|---|
| Bloat / GDV Risk | Low | High |
| Slippery Floor Risk | Low | Medium |
| Min Fence Height | 1.5m | 1.5m |
| Dig / Escape Risk | Low | Low |
Health & Common Conditions
Bullmastiff Health Issues
Flat-Coated Retriever Health Issues
Bullmastiff Suggested Tests
- OFA/PennHIP for hip/elbow dysplasia
- Echocardiogram for cardiac issues
- CERF for eye conditions
- Prophylactic gastropexy
Flat-Coated Retriever Suggested Tests
- Hip Evaluation (OFA/BVA)
- Patella Evaluation
- Ophthalmologist Evaluation (Gonioscopy)
- Elbow Evaluation
Health Risk Overview
| Risk Factor | Bullmastiff | Flat-Coated Retriever |
|---|---|---|
| Cancer Risk | Medium | High |
| Cardiac Risk | Low | Low |
| Neurological Risk | Low | Low |
| CCL/ACL Tear Risk | Low | Medium |
| Vet Burden Tier | Medium | High |
Sensitivities & Allergies
| Sensitivity | Bullmastiff | Flat-Coated Retriever |
|---|---|---|
| Skin Allergies | ||
| Environmental Allergies | ||
| Stomach Sensitivity | Low | Moderate |
| Food Allergies | Chicken, Grain |
Health Maintenance
| Care Item | Bullmastiff | Flat-Coated Retriever |
|---|---|---|
| Nail Growth Rate | Normal | Fast |
| Eye Care Needs | Low | Low |
| Anal Gland Issues | Occasional | Occasional |
Senior Care & Aging
Bullmastiff Senior Care
Common Senior Issues
- Arthritis
- Vision decline
- Cognitive changes
Senior care varies by individual health.
Flat-Coated Retriever Senior Care
Common Senior Issues
- Cancer (Histiocytic Sarcoma, Hemangiosarcoma)
- Arthritis
- Laryngeal paralysis
Decline can be sudden due to cancer - owners often report dog was 'fine yesterday' before diagnosis. Mental preparation for early loss is important.
Grooming & Care
Bullmastiff
medium maintenanceFlat-Coated Retriever
medium maintenanceLifestyle Compatibility
Bullmastiff Daily Life
Flat-Coated Retriever Daily Life
Housing & Legal Restrictions
| Restriction | Bullmastiff | Flat-Coated Retriever |
|---|---|---|
| BSL Restricted | ||
| Common Rental Ban | ||
| Insurance Blacklist | ||
| Weight Category | Under 50lbs | Over 50lbs |
Climate Tolerance
| Climate | Bullmastiff | Flat-Coated Retriever |
|---|---|---|
| Heat Tolerance | ||
| Cold Tolerance | ||
| Water Affinity | Medium | High |
Travel Compatibility
| Activity | Bullmastiff | Flat-Coated Retriever |
|---|---|---|
| Car Travel | Good | Excellent |
| Camping | ||
| Beach Friendly | ||
| Hiking Rating | ||
| Cabin Flight Eligible | ||
| Hotel Friendly Size |
Niche Suitability
| Role | Bullmastiff | Flat-Coated Retriever |
|---|---|---|
| Service Dog | Low | High |
| Therapy Dog | Low | High |
| Deep Pressure Therapy | ||
| Canicross / Bikejoring | ||
| Apartment Adaptable | ||
| Tactile / Sensory Friendly | ||
| Livestock Guardian | ||
| Medical Alert | Low | High |
Costs & Expenses
Upfront Costs
| Cost | Bullmastiff | Flat-Coated Retriever |
|---|---|---|
| Purchase Price | N/A | $1,500-3,000 |
| Initial Cost Range | $1,000–$2,500 | $1,500–$3,000 |
| Cost Tier |
Ongoing Costs
| Cost | Bullmastiff | Flat-Coated Retriever |
|---|---|---|
| Monthly Range | $180–$300 | $150–$250 |
| Yearly Range | $2,160–$3,600 | $1,800–$3,000 |
| Food / Month | $100-150 | $60-90 |
| Insurance / Month | $80-150 | $80-150 |
| Grooming / Session | N/A | $0-50 |
| Vet Routine / Year | $500-800 | $300-500 |
| Monthly Cost Tier |
Bullmastiff Lifetime Cost
N/A
Flat-Coated Retriever Lifetime Cost
$20,000-50,000
Quirks & Fun Facts
Daily Quirks
| Quirk | Bullmastiff | Flat-Coated Retriever |
|---|---|---|
| Snoring | ||
| Flatulence | Occasional | Occasional |
| Slobber Level | Low | Light |
| Smell When Wet | Moderate | Strong |
| Zoomies Frequency | Occasional | Daily |
| Counter Surfing | ||
| Digging Tendency | Low | Low |
Flat-Coated Retriever Quirks
The Flattie Lick
Notorious face-lickers - this is an appeasement and affection behavior that is hard to train out
Carrying Objects
Will greet you with a shoe, pillow, or toy in their mouth - this is self-soothing behavior, trade for a toy instead of punishing
Mud Magnet
If there is one mud puddle in a 10-acre field, a Flat-Coat will find it and lie in it
Frequently Asked Questions
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