There are 14 words that start with 'promp'.
| prompt | prompts | prompted |
| prompter | promptly | prompters |
| promptest | prompting | promptbook |
| promptness | promptbooks | promptitude |
| promptitudes | promptnesses | |
Note: These 14 words that start with 'promp' are found from the USA & Canada version of the tournament Scrabble word list.