I do somewhere between 9 to 11. It depends on the fabric and size of the needle. I usually use a tiny 12. But recently bought platinum 9 because I was having a hard time with the needle going through the batik fabric, I will not use batik again as backing. So now it is 9 or 10. The main thing is for your stitches to be uniform. I also have been hand quilting for over 25 years.