Heretofore is a rather formal and uncommon word that means "before now" or "previously". While it may add a touch of sophistication to your writing, it can also be useful to have a few synonyms ready for when you want to convey the same idea in a different way. Some synonyms for heretofore include "previously", "formerly", "hitherto", "beforehand", "earlier", "to date", "so far", "up until now", "thus far", "henceforth", and "prior to this". Using these synonyms can bring variety to your writing and make it more engaging, without sacrificing clarity or precision.