the standard size pillow form is 14" and that is so you can use a 12" pc of fabric or 12" quilt block.... it is meant to really 'stuff' the corners well and make the pillow 'poof'.... the 12 block would of course be the finished size...cut at 12.5 for 1/4" seams or 13 for 1/2" seams...I only mention this to demonstrate that if I was covering an 18" pillow form, i would use a 16" cover.... if these are foam...trim off the sharp corners with your scissors, they will look much better in the covers... just snip at a 45 deg angle to 'soften' the edges... if they are 'filled' forms...you're all set...
Last edited by deemail; 12-01-2011 at 06:02 PM.