All employers are required by law to file reports and pay taxes to the tax office on or before the last day of the month following the end of each quarter. The quarters end on 31 Mar, 30 Jun, 30 Sep, and 31 Dec. Employers registered with the tax office will be provided quarterly with the necessary reporting forms. Negative reports must be flied even though there has been no reportable activity.History: Contractors Lic. Bd. Tax and Social Security Requirements. eff 12 Feb 73, § 4.