Guests who book three nights at any participating Preferred Hotel Group hotel or resort worldwide and pay with a MasterCard through Dec. 31, 2013, will receive a fourth night free. There are 256 participating hotels and resorts. Blackout dates may apply. Visit http://insideflyerus.wpengine.com/link/?9410 to see which hotels participate and to book a stay using rate code MTKMSC.

Another offer, for Visa cardmembers, is offered year round and includes 20 to 50 percent off and free breakfast when using rate code MTKVEX. Blackout dates may apply. Visit http://insideflyerus.wpengine.com/link/?9411 to book any of the 284 hotels that are participating in the offer.