Depends on the measurements of the twin quilt.... You can cut (9) 4" strips from a yard of fabric, if the fabric is 40" wide that gives you 360" of binding . measure your length X 2, then the width X 2, add those 2 measurements together, add about 10" for mitering corners. Divide this amount by 40 to know how many strips you need, multiply the number of strips by 4 to know how many inches (yardage) of fabric you need. I can not imagine needing 2 yards. (18 strips X 40" = 720" ****that would be enough for a really giant king! (175" per side!)