Town Hall Address 1 Roosevelt Square Mt Vernon, NY 10550 United States- Westchester County Website https://cmvny.com/ County Clerk Timothy C. Idoni 914-995-3081 Mon - Fri, 8am - 5pm 110 Dr. Martin Luther King Jr. Blvd White Plains, NY 10601 United States Town Clerk 914-665-2348 9:00-5:00, Monday - Friday 1 Roosevelt Square Mount Vernon, NY 10550 United States Tax Collector 914-665-2442 9:00-5:00, Monday through Friday 1 Roosevelt Square P.O. Box 1006 Mount Vernon, NY 10550 United States Assessor 914-665-2325 https://cmvny.com/departments/assessor/ Monday - Friday, 9:00am to 4:30pm 1 Roosevelt Square Mount Vernon, NY 10550 United States Fire District 914-665-2626 470 E Lincoln Ave Mount Vernon, NY 10550 United States Water 914-668-7820 NY United States Town Hall Hours Monday - Friday: 9 AM - 4:30 PM County Westchester