26 CFR §31.6205-2

1. (a)Adjustments without interest. A State or local government employer who makes, or has made, an undercollection or underpayment of the hospital insurance taxes imposed by sections 3101(b) and 3111(b) that—
   1. (1)Are required to be paid by reason of section 3121(u)(2), and
   2. (2)Are required to be reported on returns due July 31, 1986, October 31, 1986, or February 2, 1987.
2. (b)Example. The application of the provisions of this section are illustrated by the following example: