The film is being produced and co-financed by Big Beach, with Focus Features co-financing and distributing worldwide.
Husband-and-wife team Dave Eggers and Vendela Vida wrote the original screenplay and production on the film is set to begin in the spring.
The untitled movie follows an expectant couple as they travel the United States in search of a place to put down roots and raise a family, Focus said.
"The many admirers of Dave and Vendela's writing can look forward to an edgy, breathtakingly funny, and movingly scripted film worthy of a master like Sam Mendes," Focus CEO James Schamus said in a statement Thursday. "We're thrilled that these three gifted collaborators will have the support of some of the most accomplished producers in the business."
Mendes has directed "American Beauty," "Road to Perdition" and "Jarhead."