US Airways is offering a targeted bonus of up to 100% additional miles when you buy miles through Seotember 30.

The offer is targeted, then you go to the buy miles page you have to enter your account information to see whether you’re being offered a bonus. (And there may be other, smaller, bonuses targeted to some accounts.)

At least I’m suggesting it’s targeted because of the requirement to verify your account information — although it does look like the details of the bonus is itself in the background, which suggests to me that the bonus may not vary although it’s possible some won’t be eligible.

If the offer is available to you, buying miles at a 100% bonus means buying them at a cost of 1.88 cents per mile.

US Airways is almost always selling miles on the cheap, which is to say at a price higher than I’m willing to pay but much lower than the ‘retail’ price that almost never prevails.

It’s like an Amazon discount percentage, or an Overstock one. Or a ‘supplemental sticker’ a car dealer might put on a car, that’s higher than the manufacturer’s suggested retail price.

Their 100% bonus on shared miles used to be one of the best deals out there. Even with a very large mileage balance with both US Airways and American AAdvantage I jump on buying miles at 1.1 cents apiece. Last month their transfer miles bonus got a bit more complicated and also more expensive.

Of course US Airways miles aren’t as cheap as they used to be or even as cheap as they used to be.

And you can’t get 90,000 mile Hong Kong awards in business class anymore. But now that those are 110,000 miles, you might as well go for first class which is just 120,000 miles roundtrip. Hard to argue first isn’t worth it, for just 5000 miles more each way.

Still, US Airways 100% bonus on purchased miles used to be a fantastic deal — when the miles were cheaper and the award chart was cheaper.

They run these offers all the time. (Sometimes structured a little too clever by half.)

And buying miles from US Airways is cheaper than buying the miles from American, even though US Airways miles should become American miles sometime next year.

It may be a strategically valuable play for some, but is not for me.

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.

US Airways continues to sell miles for under 1.9 cents apiece, which is lower than American’s price even though the miles will eventually become AAdvantage miles.

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