There are 15 words that start with 'beta'.
| beta | betas | betake |
| betaine | betaken | betakes |
| betaxed | betaines | betaking |
| betatron | betatter | betatrons |
| betatters | betattered | betattering |
Note: These 15 words that start with 'beta' are found from the USA & Canada version of the tournament Scrabble word list.