Airlines often add incentives to transfer hotel points to them, because the hotel chains actually pay the airlines for the miles you get. From August 22 - Sept 18 Air Canada’s frequent flyer program Aeroplan is now offering up to 5,000 extra Aeroplan miles when you transfer the equivalent of 25,000 miles or hotel points into Aeroplan miles. Registration required.Bonus structure:Hotel points -> at least 5,000 Aeroplan = 1,000 bonusHotel points -> at least 10,000 Aeroplan = 2,000 bonusHotel points -> at least 25,000 Aeroplan = 5,000 bonusBonus can be earned once per hotel partner, who include:Starwood Hotels & Resorts- Starwood Preferred Guest®Best Western International® - Best Western Rewards®Marriott® International - Marriott Rewards®Hilton Worldwide® - Hilton HHonors®InterContinental® Hotels Group - Priority Club® RewardsAccor Hotels and Resorts - A|ClubCarlsonSM Hotels Worldwide - Club CarlsonSMChoice Hotels International® - Choice Privileges®Coast Hotels & Resorts – Coast RewardsHyatt Hotels & Resorts® - Hyatt Gold Passport™Shangri-La Hotels and Resorts – Golden CircleWyndham Worldwide - Wyndham Rewards®TPG reader Martin emailed me that he was excited for this promo, since he’d now have a good reason to transfer the Wyndham points he bought on the cheap, back in May during the Discover America promotion.This also means 20,000 Starwood points transferred to Aeroplan would equate to 30,000 Aeroplan (5,000 Aeroplan bonus + 5,000 Starwood bonus when you transfer in 20,000 point increments +20,000 = 30,000). 20,000 points can get you a free night at a category 6 hotel (like W South Beach) or 2 nights at a category 4 property, so you should do a cost benefit analysis before you do a any transfer. If you want to do a business class trip to London, 1/3 of a roundtrip flight may be more valuable than 1 night at a high-end hotel. It all depends on how you value each currency.Sign up for our daily newsletterEmail addressSign upI would like to subscribe to The Points Guy newsletters and special email promotions. The Points Guy will not share or sell your email. See privacy policy.Personally, I have enough Amex points/Airline miles that I generally use my hotel points for hotel stays, but this may make sense if you’ve got a bunch of hotel stays and need airline miles. Even though Aeroplan increased their award charts this summer, there are still decent values to be had, like their 90,000 mile business class award from North America to many places in Western Europe. Remember - you can redeem Aeroplan miles on all Star Alliance partners and they have very flexible routing rules, that include two stopovers and round-the-world routing.As always, Loyalty Traveler has great analysis of this promo.TERMS AND CONDITIONS:Maximum 5,000 Bonus Aeroplan Miles can be earned per participatingpartner loyalty program per Aeroplan Member during this promotion. Tobe eligible for this offer, Aeroplan Member needs to register for thepromotion and convert hotel partner loyalty points between August 22 and September 18, 2011. Registration can be done after the conversionas long as they are both within the promotional period. Bonus mileswill be credited to the member’s account by Aeroplan up to eight weeksfrom the date the member makes his/her request with the partner.