29 CFR § 2520.104a-5 - Annual reporting filing requirements.
(a) Filing obligation. Except as provided in § 2520.104a-6, the administrator of an employee benefit plan required to file an annual report pursuant to section 104(a)(1) of the Act shall file an annual report containing the items prescribed in § 2520.103-1 within:
(2) Seven months after the close of any plan year which begins after December 31, 1975, unless extended. See “When to file” instructions of the appropriate Annual Return/Report Form.
(b) Where to file. The annual report described in § 2520.103-1 shall be filed in accordance with and at the address provided in the instructions to the Annual Return/Report Form.