I recently completed a Downey Quilt for kids that they had sent me, and also sent one that I had made. But, I was floored when it cost me $10 to send through USPS. How do you send yours back? Any info welcome.

I use Flat Rate boxes and use the smallest I can squeeze my stuff into. Saved me lots of $ over time.

USPS. Though I usually send back 2 or 3 at once. I'm thinking that one of the Tyvek envelopes sent priority (not flat rate) might be less for a single quilt.

I use UPS, mostly because I like the guy that owns it. And I know he takes extra care with packing my quilts.

NOT at all...those tyveks are only good about 1 pound...then the prices are more than a flat rate box...

$10 is not bad really especially if you insured and got tracking like you were supposed to!
At UPS it would have cost $15 or more!

Shipping is very costly now and going up in April right about tax time!

I use flat rate mailers. I like them for just about everything.

I'll weigh my options out when I get ready to mail mine out.

Slighty OT, but I've heard to never label it with "quilt" to say "blanket", "bedspread" or some such to discourage theft.

Sorry, can't help out here. My brother owns a FedEx business so I get my shipping for next to nothing.

USPS always!