Town Hall Address 49 Main St New Castle, NH 03854 United States- Rockingham County Website http://www.newcastlenh.org/pages/index Town Clerk (603) 431-6710 http://www.newcastlenh.org/Pages/NewCastleNH_Clerk/index Mon, Wed & Thu 8 A.M. - noon P.O. Box 367 New Castle, NH 03854 United States Tax Collector (603) 431-6710 Mon, Wed & Thu 8 A.M. - noon P.O. Box 367 New Castle, NH 03854 United States Assessor (603) 431-6710 http://data.avitarassociates.com/logon.aspx?ReturnUrl=/ Mon, Wed, Thurs, Fri 8:00am - 2:00pm CLOSED ON TUESDAYS P.O. Box 367 New Castle, NH 03854 United States Building (603) 431-6710 Ext. 15 P.O. Box 367 New Castle, 03854 United States Zoning (603) 431-6710 P.O. Box 367 New Castle, NH 03854 United States Fire District (603) 436-1132 P.O. Box 367 New Castle, NH 03854 United States Town Hall Hours Mon, Wed, Thu & Fri 8 A.M. - 2 P.M. County Rockingham