Taxes may be paid in person at the Treasurer’s Office at 500 N Capital Ave. or mailed to: Bonneville County Tax Collector 605 N Capital Ave. Idaho Falls, ID 83402 Office hours are 8 a.m. to 5 p.m., Monday through Friday. We accept cash, checks, money orders or cashiers checks. When mailing payments please do so EARLY. Many postal drop boxes have an early pick-up time. Payments made after pick-up times will be postmarked the NEXT day. It is recommended that you mail payments at least a day or two prior to the deadline.