Contacting Interserve The easiest way to contact Interserve during regular business hours is via telephone. You can also contact us by email, mail, and fax. Or, feel free to stop by our office Monday through Friday, 8:00 a.m. to 6:00 p.m. and Saturday, 9:00 a.m. to 2.00 p.m. Visit us at our new loca...