There are 417 13-letter words that end with 'on'.
Note: These 417 13-letter words that end with 'on' are found from the USA & Canada version of the tournament Scrabble word list.
Also see words end with ion, ron, ton, oon, son, lon, eon, gon, con, mon, don, non, hon, pon, yon, bon, kon, xon, zon, fon, uon, won, jon, von, aon.
3-letter words end with 'on' (11)