Jo Konta came through the final round of qualifying but Kyle Edmund suffered a shock defeat to leave six British singles players at the US Open.
Konta beat Austria's Tamira Paszek 6-4 3-6 6-2, taking her winning run since Wimbledon to 13 matches.
Edmund led 5-2 in the final set and had three match points but lost 6-2 0-6 7-5 to Japan's Yoshihito Nishioka.
Naomi Broady lost 7-6 (7-4) 2-6 6-4 to Estonian Anett Kontaveit, Brydan Klein lost 6-3 6-3 to Australia's Matt Ebden.
Konta guarantees herself £26,000 for reaching the first round in New York, where she will join compatriots Andy Murray, Aljaz Bedene, James Ward, Heather Watson and Laura Robson.