As soon as you get your puppy, that is!
In fact, many dogs are switched directly from mother’s milk to raw food, with no kibble in between. The sooner you can start your puppy on raw food, the better, but if your puppy has been sick or you’d like to delay feeding raw for a little while longer, you can. A raw diet can begin at any age. Many dogs do not transition until they are fully grown adults, which is much later in their lives.
It is preferable to begin feeding your puppy a raw diet as soon as possible. Waiting until adulthood simply means that your puppy will miss out on the benefits of a raw diet while she is young and could have benefited the most. Puppies as young as 5 weeks old can start eating soft raw food.