I also have had luck shipping with FedEx for domestic US.
If your work has a preferring shipper and they allow personal packages you can save loads, especially if going to another business

For example I can usually ship complete bikes from the east coast to the west for under $25, bare frames about half.
Also noticed shipping to larger cities (standard routes for carrier) are cheaper than the smaller locals
Size is the most important specification to consider, as bikes overall don't weigh much in comparison to the size of package.