From 3 – 5 terrestrial planets similar to those in the Solar System formed around each star in α Cen AB in simulations that began with a disk of embryos inclined ≤ 30° to the binary orbital plane. We found that for wide and close binary star systems, the binary periastron (closest approach) and apastron (maximum stellar separation), respectively, are the most influential stellar parameters on planetary accretion. Terrestrial planets formed in Earth-like (∼1 AU) orbits around individual stars in binary systems with periastron ≥ 7 AU, and surrounding close binary stars with stellar apastrons ≤ 0.2 AU. Approximately 50 - 60% of binary star systems - from contact binaries to separations of nearly a parsec - satisfy these constraints. Given that the galaxy contains more than 100 billion star systems, a large number of systems can potentially harbor Earth-like habitable planets.