| Baeddan | Man | Welsh Names |
| Bedwyr | Man | Welsh Names |
| Bethan | Woman | Welsh Names |
| Bethwyn | Woman | Welsh Names |
| Betrys | Woman | Welsh Names |
| Bevan | Man | Welsh Names |
| Beynon | Man | Welsh Names |
| Blodwyn | Woman | Welsh Names |
| Bowen | Man | Welsh Names |
| Braith | Woman | Welsh Names |
| Bran | Man | Welsh Names |
| Branwen | Woman | Welsh Names |
| Briallen | Woman | Welsh Names |
| Bricen | Unisex | Welsh Names |
| Broderick | Man | Welsh Names |
| Bronwen | Woman | Welsh Names |
| Bronwyn | Woman | Welsh Names |
| Brynn | Woman | Welsh Names |
| Buddug | Woman | Welsh Names |