The simple answer to this question of how often to bathe a dog is: how often do you want to bathe your dog? Unless a dog has skin problems, there is no specific need to bathe the dog except to make him a more enjoyable companion.
Just like people, some dogs get stinky faster than others. I have known dogs that have never had a bath in their life and do not have an unpleasant smell, but my own dogs get bathed weekly.
Bath Time’s the Best!
No matter what age, size, sex or breed of dog you have, you can make bathing a pleasant part of your dog’s life if you do two things:
- Teach your dog to associate bathing with things he loves.
- Take it slow and easy.
Associate Bathing with Good Things
Many dogs find bath time unpleasant—and who can blame them? It involves being restrained, soaked with water (which some dogs really dislike), slathered in scented suds and handled in various, sometimes uncomfortable ways. However, you can help your dog learn to tolerate—and maybe even enjoy—bathing.
The secret is to teach your dog that bathing is always followed by things he loves. If your dog learns that bath time reliably leads to wonderful stuff—like special treats, brand-new chew toys, the start of a favorite game, a walk in the park or dinnertime—he’ll soon learn to feel much better about it. And if he feels much better about getting a bath, he’ll behave better too, which will make bath time easier for both of you. So whenever you bathe your dog, help him to associate bath time with things he enjoys. Right after putting him into the tub, give him a tasty treat, like a small bite of chicken or cheese. If your dog seems nervous about running water, give him a treat right after turning on the tap. After toweling him off, immediately invite him to play a rousing game of tug or give him a handful of his favorite treats. With repetition, your dog will probably decide that getting a bath is fun, not frightening or stressful.
General Dog Bathing Guidelines
I recommend you bathe a dog with normal skin once a month with dog shampoo or human baby shampoo. If you want to bathe more often than that, use a soap-free or moisturizing shampoo to prevent the skin from becoming dry.
Source: How often to bathe a dog