US Airways is running a 100% bonus for mileage purchases through December 20th.

For purchases of 50,000 miles you get 50,000 bonus miles, and your 100,000 miles cost you 1.88 cents per mile.

They ran this targeted last month and in July. They ran it non-targeted in August. October and also a couple of weeks back they had the much better 100% share miles bonus.

US Airways IT Challenges Making Bookings Limit Value Somewhat

US Airways has been dubbed the ‘consolidator of Star Alliance premium class seats’ (credit to eponymous coward) since seats that aren’t expected to be sold (distressed inventory) tend to be offered as awards, and US Airways has been the most aggressive about letting members straight up buy those seats cheaply via purchased miles — even putting awards on hold before buying the miles (which post instantly).

Here’s my guide to using US Airways miles to book awards.

US Airways though has difficulty ‘seeing’ some partner award inventory, especially Lufthansa’s and especially intra-Europe though also transatlantic and also ANA space as well. That makes the miles a bit less valuable.

The American Merger and US Airways Exit from Star Alliance

US Airways has merged with American. We expect reciprocal earn and burn to begin January 7. US Airways should depart Star Alliance March 30 and enter oneworld on March 31.

That means you can book an award now, redeeming for travel on Star Alliance. You can even wait until March 30th to do so (although I wouldn’t), for travel as far out as 330 days into the future. The only hiccup is if schedule changes force rebooking, the airline will only be able to re-accommodate you on oneworld airlines after March 30th.

Of course if American and oneworld is your thing, this purchase bonus offer is cheaper than American sells miles.

No Airfare Spending Bonuses for the Mileage Purchase

US Airways mileage purchases are processed by points.com which means they don’t show up as airfare, and thus don’t earn bonuses from credit cards like Chase Sapphire Preferred (double points) or American Express Premier Rewards Gold (triple points) that bonus airfare spend.

Should You Buy Miles With This Offer?

Buying miles at a 100% bonus from US Airways used to be an amazing deal. Four years ago their award chart was less expensive (e.g. 80,000 miles for business class to Europe).

And prior to September 2010 miles normally cost 2.5 cents apiece.

In October 2011 they raised the standard price of miles to 3.5 cents apiece.

Since US Airways runs mileage purchase bonuses nearly every month, though sometimes targeted and other times in varying amounts, they’ve more or less jacked up the price only to be able to discount it, making the discounts look better than they actually are. (See also ‘Groupon’.)

Make no mistake, they can still be a good deal, but not good enough in my view to stock up miles speculatively. Instead, I’d use this deal to top off an account towards a specific award or to buy outright a ticket that you can immediately book (getting airfare at a discount).

The way to do this ‘non-speculatively’ is to put the award you want on a three day hold, then buy the miles, and ring back to ticket the award.

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