Last Friday I posted that the last day to purchase US Airways miles for a 100% bonus was that day. I just noticed today that US Airways has actually extended the expiration for this promotion to Friday December 7th – 1 week later than it was supposed to end. This promotion runs quite often, so if you are interested but not ready to take the plunge in the next few days, chances are you’ll see this promo again (fingers crossed!). You can read more about the promotion and if it is worthwhile for you in this prior blog post, but to quickly recap:

• Earn a 100% bonus on all purchased miles up to 50,000 miles
• Promotion runs through December 7, 2012
• Miles cost 3.5 cents each (plus taxes and fees)
• Your US Airways account must be at least 12 days old
• Purchase miles here

Typically, miles are sold for $0.035, but with this promotion you can think of each mile costing $0.0175. If you go all in, the 100,000 miles will cost you $1,881.25. These 100,000 miles can be used for a round-trip business class ticket from the US to Europe. Purchasing this ticket will typically cost you at least $3,000 (and that is on the real conservative side probably).

I personally do not like speculatively purchasing miles, but if you have a trip in mind, this deal could potentially be in your favor, especially if you are looking for a business/first class ticket. You can check out the US Airways award chart here to see the number of miles needed for each route.