There are 15 words that start with 'betr'.
| betray | betrays | betroth |
| betrayal | betrayed | betrayer |
| betroths | betrayals | betrayers |
| betraying | betrothal | betrothed |
| betrothals | betrotheds | betrothing |
Note: These 15 words that start with 'betr' are found from the USA & Canada version of the tournament Scrabble word list.