🐾 Pets · Dog breeds
What Size Collar & Harness for a Bullmastiff?
For an adult Bullmastiff, a XL collar and XL harness are the usual starting point, based on a typical neck of 51–66 cm and chest of 76–96 cm. But every dog is different — measure yours and use the two-finger rule before buying.
Collar: XL · Harness: XL
Typical neck 51–66 cm · chest 76–96 cm · weight 45–59 kg
⚠️ Measure your dog — breed is only a starting point. A Bullmastiff's build varies a lot between individuals, and a collar is a safety item. Measure the neck snug, add about 2-3 cm (the two-finger rule), and confirm against the specific collar's size guide before buying.
Typical measurements for an adult Bullmastiff:
| Typical range | Recommended size | |
|---|---|---|
| Neck (collar) | 51–66 cm (20–26 in) | XL |
| Chest (harness) | 76–96 cm (30–38 in) | XL |
| Weight | 45–59 kg | — |
Got a tape measure handy? The collar & harness calculator turns your exact measurement into a size with the two-finger fit built in.
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