Barbara Byrne Denham of Reis Denham sees landlords becoming less aggressive with rent concessions.

NEW YORK CITY—The multifamily sector is containing the effects of increased supply on occupancy, as the national vacancy rate increased by just 10 basis points during the third quarter to 4.5%, a smaller-than-expected uptick, Reis said Tuesday. Even as vacancies rose during Q3, so did both asking and effective rents on a national basis.