US Airways’ Dividend Miles bonus promotion for buying or gifting miles ends May 31, 2013. You can earn a bonus of 25 to 100 percent depending on the number of miles you buy as follows:

Buy 5,000 – 9,000 miles, get a 25 percent bonus
Buy 10,000 – 19,000 miles, get a 50 percent bonus
Buy 20,000 – 29,000 miles, get a 75 percent bonus
Buy 30,000 – 50,000 miles, get a 100 percent bonus

I do not recommend buying miles as a matter of practice. However, if you are near an award threshold, have a specific trip in mind, and have identified available award inventory, it can make sense. If you can pick up some bonus miles in the process, so much the better. YMMV.

-MJ, May 23, 2013