Itâs time to pay Johnson City and Washington County property taxes for 2020. The deadline for city taxes is Dec. 31; county taxpayers have until Feb. 28 to settle their bills. Johnson City property taxes must be postmarked by Dec. 31 or earlier to be accepted without penalty. Late fees and interest will begin to accrue on unpaid bills starting Jan. 1. Property taxes can be paid at the Johnson City Municipal and Safety Building located at 601 E. Main St., weekdays from 8 a.m. to 5 p.m. Payments can also be mailed to the City of Johnson City, P.O. Box 2227, Johnson City, TN 37605.