Michael Ackerman, a Seattle Realtor with Coldwell Banker Bain, blogs about back up offers. What are they? How do they work? A back up offer is made by a buyer when a home that they want to purchase is already in contract with another buyer. If for any reason, the first offer does not close, the fully executed back up offer automatically moves into first position. If you have any comments or questions, please send your email to email@example.com or visit www.mackerman.com.