There are 54 10-letter words that end with 'sion'.
Note: These 54 10-letter words that end with 'sion' are found from the USA & Canada version of the tournament Scrabble word list.
Also see words end with ssion, usion, rsion, ision, nsion, asion, lsion, osion, esion.
6-letter words end with 'sion' (5)