37 C.F.R. § 2.181
Term of original registrations and renewals
(a)(1) Subject to the provisions of section 8 of the Act requiring an affidavit or declaration of continued use or excusable nonuse, registrations issued or renewed prior to November 16, 1989, whether on the Principal Register or on the Supplemental Register, remain in force for twenty years from their date of issue or the date of renewal, and may be further renewed for periods of ten years, unless previously cancelled or surrendered.
(2) Subject to the provisions of section 8 of the Act requiring an affidavit or declaration of continued use or excusable nonuse, registrations issued or renewed on or after November 16, 1989, whether on the Principal Register or on the Supplemental Register, remain in force for ten years from their date of issue or the date of renewal, and may be further renewed for periods of ten years, unless previously cancelled or surrendered.
(b) Registrations issued under the Acts of 1905 and 1881 remain in force for their unexpired terms and may be renewed in the same manner as registrations under the Act of 1946.
(c) Registrations issued under the Act of 1920 cannot be renewed unless renewal is required to support foreign registrations and in such case may be renewed on the Supplemental Register in the same manner as registrations under the Act of 1946.