you will get lots of answers on both sides of the fence- there are people who pre-wash everything- regardless of size- there are some who pre-wash nothing ever- then there are some of us who pre-wash some of the time- with pre-cuts I generally do not pre-wash- if they are batiks or hand dyes and deep saturated colors I am worried may run I will do a color test to see (dampen a piece & rub a piece of white muslin or a paper towel on it to see if color comes off) my 'rule of thumb' for pre-washing is- if the fabric (whole yardage-not precuts) smells funky, feels funky, is stiff, might bleed, (batiks/hand dyes) , is a loose weave (needs tightening up a bit) I prewash- if it has none of these issues I may not- I do always wash my finished quilts- as soon as the binding is done- last step to a finished project is the laundering step. everyone has their own ideas concerning pre-washing. but I pretty much never pre-wash pre-cuts until they are used/finished