I posted recently about this problem and got some great advice. For another newish quilter here are some other things to consider:

I had not ironed my backing - when I did I gained more room than I thought possible. Not inches and inches, but ... a little bit.

I am bringing the backing over for the binding and do not have to have more than ... an inch? smaller? At least not as much as I sometimes have.

If all else fails and I really don't want to use your great suggestions I can trim a tiny bit off both top and bottom - 1/2 inch from each gains an inch overall.

It's not even pinned yet, but it's all laid out and ... I think I can make it work.

Here's the post where I showed the top.
http://www.quiltingboard.com/t-129716-1.htm

I'd be going thru my stash and looking for a matching or coordinating color to add a 2", 4", whatever" frame all around the backing. I'd sure not mess with the top!

I'm inclined to agree with GrannieAnnie (especially if it's not quilted yet). Mind you I'm no expert on bringing the backing over to use as binding. I love binding, so I make binding and stitch by machine on the front and handsew the back (IMHO that is one of the most satisfying things about quilting:)).

Let us know what you decide, and we would love to see it when it's done. Happy quilting.

Sew another 6 inch piece on...then sew it into a tubr. cut the tube so that the extra material will be in the center of your backing. The extra material will make a nice design....you also could sew a strip of 6 inch squuares and do the same...the strip will be in the middle of your backing.

i use pieced backs often; i do not understand this 'tube' instruction, sorry ?...

Brilliant tip!!! Thanks!! You just solved my problem!!!!! Just off to my sewing room to do it!!!! Love this board and all the fantastic ideas shared!!

That is a brilliant idea! Eliminates so much of the stress of centering, measuring, etc.

That's going in my bag of tricks!
Thanks!

Just sew the extra piece to your backing piece then sew it to the other side of the backing which would create a tube. then cut the backing making sure your added piece is in the middle or side if you prefer. this way it looks like the added piece was planned.