Grooming and coat
Why does my dog's undercoat come out in clumps?
Last updated 23 September 2026 · How we write and check this
Short answer
Clumpy undercoat shedding is a normal part of a seasonal coat blow in double coated breeds, when large sections of dead undercoat release at once rather than gradually. This is different from thinning or bald patches, which suggest a health issue rather than normal shedding and are worth a vet check.
Normal seasonal clumping
During a coat blow, dead undercoat that has built up over months detaches in larger sections rather than the fine, steady shedding seen the rest of the year, which is why owners often find fist sized tufts on the floor or caught in the coat during brushing in spring and autumn.
How to tell it is going well
If the coat underneath the clumps still looks even and covered, and the dog is otherwise behaving normally, this is typically just the coat doing what it is supposed to do. Brushing daily with an undercoat rake during this period helps the process along and clears the loose clumps faster than leaving them to fall out on their own.
When clumping points to something else
Clumps that leave visible thin or bald patches underneath, rather than an even coat, or that happen well outside the normal spring and autumn window, can indicate a hormonal imbalance, nutritional gap, or skin condition rather than a typical coat blow, and this pattern is worth having a vet assess.
Key takeaways
- Clumpy shedding is normal during a seasonal coat blow in double coated breeds.
- An even coat underneath the clumps is a good sign that shedding is progressing normally.
- Bald or thin patches under the clumps, or clumping outside the usual season, deserve a vet check.