Southwest is offering a mystery bonus right now through November 10th. With this one you have to log into your account to see how much your offer is for. I was targeted for 40% bonus (when purchasing 5,000 or more) which is not great. Even at the 50% bonus offering, this deal is not good. The only way I can see buying points at the 50% bonus level (~1.83 cents per point) is if you are short on a point redemption and need to top off your account. Of course you should always make sure you compare the cost of points to the value of the flight that you want to book.

Southwest Mystery Bonus Up To 50% 

Mystery Bonus! Buy Southwest Rapid Rewards points and get up to 50% bonus.

I was targeted for 40% bonus.

• Offer is valid between October 17, 2017, 12:00:01 a.m. CST and November 10, 2017, 11:59:59 p.m. CST.
• Member will receive 40% bonus points when they purchase a minimum of 5,000 Rapid Rewards® points.
• A minimum 5,000 points purchase threshold must be met on a per transaction basis, in order to qualify for bonus points.
• Points can be purchased in blocks of 1,000 and a daily maximum of 60,000 points can be purchased by a Member with no annual maximum.
• Please allow 72 hours for points to post to the applicable Rapid Rewards account.

Bottom Line

I could see looking at this if you have some left over points that you want to burn through rather then pay for a flight and you are a little short. Make sure you compare the cost of points to the value of the flight that you want to book to make sure that the deal makes sense. While points do give more flexibility sometimes, most likely this is not a good deal for most people.

Related

Southwest Airlines Announces Hawaii Service in 2018

New Public Offer For Southwest Companion Pass For Free (California)