ACS USA Contact Customer Service Numbers Home» ACS» ACS USA Registration Service: +1 (800) 333-9511 Call From Outside North America: (614) 447-3776 General Inquiries: +1 (800) 227-5558 Headquarters: 1155 Sixteenth Street, Washington, DC 20036, Northwestern United StatesEmail About Registration At: service@acs.orgTiming: Monday through Friday (except holidays) from 8:30 a.m. to 5:00 p.m. Eastern Time.The American Chemical Society abbrevaited as ACS is a scientific society that supports scientific inquiry in the field of chemistry. It was initiated in 1876 by the association of 35 chemists at the University Building in the New York University. It is a publicly held, Federal Income Tax free nonprofit organization. It helps to improve the living standards of the people through the transforming power of chemistry. It is an authorized independent membership organization and has nearly 163,000 members at all degree levels and in all fields of chemical engineering, chemistry and various related fields.