Me too, right now I have cones of light grey and a medium beige. I hardly ever use white for piecing. Light sagey greens sound like another good choice.

When I began quilting about 12 years ago my instructor told us about using light grey and at that time she said it was difficult to buy it in large spools so she grabbed whatever size spools she could.

This is so smart! I never thought of it and have been buying way too much thread. I'll get some larger amounts of gray going forward!

Well now, I learned something new this morning! thanks y'all!

If I am piecing, I use whatever color I have, top and bottom, unless it shows through on light colored fabrics....uses up all those extra bobbins! For quilting, I use a matching thread on the bottom (my quilting isn't that exceptional) and a color on top that will blend the most.

I use a grayish white, I think it is called silver, in superior bottom line thread. I use it in the bobbin and what ever color I want with the top thread. It just disappears into the fabric, I use it for piecing and quilting. It is very fine so a bobbin goes on forever.

Be aware that on dark colors it may show way more than you will like. My first quilting class I was told the grey thread theory and as the teacher was a bit of a quilt Nazi, that is what I used. Just before quilting I had to stop and un-sew a lot of blocks because the grey thread did not disappear into the dark purple fabric I was using. Just a little heads up.

also use a grey or tan thread in the large cones, it seems to work very well

I use, white, black, tan, medium grey, and dark gray....The most important thing to add to the mix is your brain.... Look at the first sewing and see if it is going to work, sometimes it does and sometimes it doesn't....you do need to use your eyes to know for sure !!!!!!!!!!!!!!!!!!!!!

I'm with Deb, the taupe that I use blends with all colors. However, at the moment I'm trying to use up all the colors of the rainbow from my clothing construction days and since I am piecing scrapy quilts all the different colors work well without trying to match a thread color to a fabric.

I usually use grey, especially if my fabrics are all different colors as in a scrappy-type quilt. If the fabrics are earth tones then I choose an ecru color. I find that I can always buy these colors in bulk spools so I end up saving a lot of money not buying multiple small spools of a matching color.