US Airways is back with another buy miles bonus through March 26.

When you go to the purchase miles offer, you have to verify your account details.

Then you’ll see the bonus your account is eligible for.

My account was offered a 100% bonus:

Another account I checked received a 75% bonus offer:

Still a third account was offered a 50% bonus:

I understand that some will receive a 25% bonus as well.

Is This a Good Deal? If You Have a US Airways Credit Card, Should You Buy?

US Airways ran — both targeted and non-targeted — versions of the 100% purchase miles or share miles bonus for most of 2013. This airline has been the single most aggressive in selling miles, and at a price point lower than most other carriers offer their miles.

Of course, Star Alliance carrier Avianca’s LifeMiles program sells miles even cheaper a few times a year.

I wouldn’t consider a 25% or even 50% bonus unless I was literally going to buy miles at ‘list’ price. And I wouldn’t stockpile miles even with a 100% bonus, which yields a price of 1.88 cents per mile all-in.

US Airways 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 for redeeming Star Alliance awards.

My advice is to use this offer only to top off an account towards a specific award — and you can generally place awards on hold and then buy the miles, calling back to ticket the held reservation.

I wouldn’t buy miles speculatively at nearly 2 cents apiece. This purchase bonus offer is cheaper than American sells miles. US Airways should depart Star Alliance March 30 and enter oneworld on March 31.

But there’s also uncertainty about the US Airways award chart over the course of the next year, before US Airways miles become American AAdvantage miles (and indeed, some uncertainty about what changes will come to the AAdvantage award chart and rules once the carriers do fully integrate).

Make no mistake, they can still be a good deal, but not good enough in my view to stock up miles speculatively.

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

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.

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