We don't use any of the bigger carriers. We have an account with Pitney Bowes, we ship everything to our customers / consumers who order from us via USPS Priority Mail Signature Confirmation. We also ship thorugh a 3rd party service: Pitney Bowes. We've only ever had one problem doing this. And that's with shipping to P.O. Boxes, rather than the receivers name signing for the package, the "sorters" will sign for it. But that's only when we ship to a P.O. Box.