There are 156 10-letter words that start with 'per'.
Note: These 156 10-letter words that start with 'per' are found from the USA & Canada version of the tournament Scrabble word list.
Also see words start with peri, pers, perf, perc, perm, perp, pere, perv, pert, pero, perd, pera, peru, perk, perj, pern, perr, perl, perb, perg, perh, perq.
4-letter words start with 'per' (7)