Washington County Tennessee Residents Will Have One Extra Day To Pay Their 2014 Property Taxes. Trustee Monty Treadway Will Open His Doors At The Jonesborough Office From 8:30 To 5 This Saturday. No Credit Card Or Partial Payments Will Be Accepted. This Will Be The Last Day Of The 2014 Collection Period. Beginning March 1st, There Will Be A 1.5 Percent Interest And Penalty Added To What Is Owed. Treadway Also Announced That New Software Is Being Installed In July That Will Allow The County To Accept Credit Card And Online Payments During The 2015 Tax Season.