Through October 1, TACA is selling miles in its Distancia program at half-off. Normally 2.5 cents a mile, they’re selling at 1.25 cents a mile.

• Minimum purchase required: 1,000 Miles
  
• If you wish to buy more than 32,000 Miles, Please make another transaction. You can make as many transactions as you like.
  
• *Prices do NOT include local taxes

There appears to be no limit to the amount of miles you can buy. However, it also appears that the website hasn’t been updated yet to allow purchase of the miles at the discounted price. I imagine that will be fixed shortly.

TACA partners with both United and Iberia, however it appears as though redemptions on those carriers can only be done in coach (making miles purchase less of a good deal). You can fly non-stop from Washington-Dulles to Buenos Aires, for example, but only in coach. Business class redemptions actually need to be done on TACA, which will frequently involve connections. And despite the award chart including business class levels to Asia, it doesn’t actually seem possible to accomplish such a reward.

Still, for folks interested in redeeming in premium cabins on TACA and Avianca, this seems an excellent deal. TACA Distancia miles do expire after 12 months of account inactivity, however, so only load up on miles if you’re certain you can extend the life of your account (and not being all that familiar with the Distancia program myself, I do not know what kinds of account activity qualify).

Discussion of the deal on Flyertalk is here.