D.C. Mun. Regs. tit. 9, § 135
135.1 Duplicate copies of all withholding statements (Form D-2) or approved substitute withholding statements shall be sent to the District by each employer with the Form D-1 that is due on the last day of January; or with the employer's final return, if submitted before the end of the calendar year. For years beginning January 1, 1982 and thereafter, withholding statements shall be submitted with Form FR-9008.
135.2 Form D-1 shall be accompanied by a list (in the form of an adding machine tape or a written itemization) setting forth the items of tax withheld at source as shown by the withholding statements (Form D-2).
135.3 If an employer's total payroll consists of a number of separate units or establishments, the duplicate Forms D-2 may be assembled accordingly and a separate list or tape submitted for each unit.
135.4 If separate lists or tapes are submitted in accordance with § 135.3, a summary list or tape shall be submitted. The total of the summary list or tape shall agree with the corresponding entry made on Form D-1.
135.5 If the number of the duplicate statements is large, the statements may be forwarded in packages of convenient size.
135.6 If statements are forwarded in packages under § 135.5, the packages shall be identified with the name of the employer and consecutively numbered. The number of packages shall be indicated immediately after the employer's name on Form D-1. Form D-1 and the remittance shall be filed in the usual manner, accompanied by a brief statement that Forms D-2 are in separate packages.
SOURCE: Commissioners' Order 56-1431 effective July 24, 1956, 16 DCRR § 310.8; as amended by Commissioners' Order 71-6 effective February 25, 1971, 17 DCR 567 (March 8, 1971); by Final Rulemaking published at 30 DCR 1453, 1454 (April 1, 1983); and by Final Rulemaking published at 32 DCR 1453 (March 8, 1985).