In April United offered a 40% discount on purchased miles promoted to its Facebook and Twitter fans.

The offer is back and only available through Wednesday at 11:59pm Central.

If you purchase between 15,000 and 100,000 miles the cost is 2.1 cents per mile plus tax.

You can’t use it for less than 15,000 miles so if you need just a few thousand for your next award this is no help.

And the price is too high just to bulk up your account.

But if you need some miles towards your next international business class award, and you have a reasonable likelihood of redeeming that award in the near-term, this is the lowest price that United offers to sell miles.

Of course, it’s not that much less than you can straight-up buy points from Chase Ultimate Rewards at and transfer them into United. So again, this isn’t a screaming deal or a speculative play. But still worth noting.

(HT: Lucky)