The amount of thread you use for a quilt depends on the size of the quilt and how dense your quilting is. For example, I just finished a quilt about 60x80", and I used about 300-350 yards of thread, based on using all of one bobbin and part of another. It was a loose meander, not at all dense. BYW, I use a lot of cone thread, especially the mini cones of 1000 yards. Big cones are 5000 yards. I also generally use Superior Threads of Aurifil products, but definitely not serger thread!Pam