white.....unless I am sewing black or another dark color....if I am piecing, usually whatever thread color I have works fine....bobbin thread for piecing is the same way, whatever I grab.....If I am fmq, I try to match, or will use white/lt. gray....sometimes I want the stitching to show and will use a contrasting color.....I guess I am saying I am not fussy for thread color when piecing...LOL