There are 261 words that start with 'back'.
Note: These 261 words that start with 'back' are found from the USA & Canada version of the tournament Scrabble word list.
Also see words start with backs, backb, backl, backc, backf, backw, backh, backd, backp, backg, backr, backt, backe, backa, backi, backo, backu, backy, backm.
5-letter words start with 'back' (1)