Talk:How to Download and Play the Game/@comment-25712820-20170619084216/@comment-26020095-20170625070525

people mostly spend money in game for Quartz, which is the currency you use to do gacha scouts. you usually get them from login bonuses, clearing story maps, events, and trading Quartz fragments (obtained from weekly missions), so if you play enough and save, there should be no problem going full F2P. however, FGO, like other games, tend to have a lot of limited scouting boxes with limited characters that are either powerful... or your favorite. so that's where people spend their F2P quartz crystals on, and for some, they use RL money to buy quartz to scout even more, until they get whoever they want. you get the point.

tl;dr it is definitely possible to play FGO without spending money.