The bonus that I have seen is 80% (could be 100% to some) and select members have had their purchase limit raised to 120,000 points from the yearly maximum of 60,000 (both before any additional bonuses).
You can check your IHG Rewards Club buy points offer here.
The price of a point under the 80% bonus when 60,000 points is purchased:
The price of a point purchased at the 80% bonus is 0.64 cents each.
Does it make sense to purchase points?
Purchasing points merely because they are on sale doesn’t make sense. If you have a good use for them, buying can lower the price of the stays considerably.
Usually using points make sense at the most expensive properties, during PointBreaks when some hotels are just 5,000 points per night or when the paid rates are through the roof due to some event in the city.
This is the first time this year that I have seen some members being eligible for raised purchase limit. IHG Rewards Club and Points.com (company that handles points sales for them) have likely upped the limit for those that have purchased points earlier this year and thus maxed the yearly limit.
The 80% bonus that my account was eligible for is not the highest that IHG Rewards Club tends to offer during these sales. Unless you need some points now, I would wait for 100% purchase bonus to resurface.
Here are the terms and conditions of this offer:
For select members only: you can now buy 60,000 more IHG® Rewards Club points this year. Plus, buy 30,000+ points and get 80% more in bonus points! Only to December 16, 2016.
Offer available for purchases made between 12:00 AM EST December 12, 2016 and 11:59 PM EST December 16, 2016 inclusive. This is an exclusive, non-transferable offer for intended recipient only and may not be forwarded. Through December 16, 2016members may purchase a maximum of 120,000 points per calendar year. Bonus points will be awarded upon completion of the transaction. Offer is subject to change. Offer cannot be combined with any other offer. Only purchases made online are eligible for bonus.