Notice 2021-11, page 827.

Notice 2021-11 modifies Notice 2020-65 by providing additional tax relief to taxpayers affected by the Coronavirus Disease (COVID-19) emergency, pursuant to the Consolidated Appropriations Act, 2021. Notice 2020-65, issued on August 28, 2020, gave employers the option to defer the employee portion of Social Security taxes (for employees whose wages are below a certain amount) from September 1, 2020, to December 31, 2020. Any taxes deferred under Notice 2020-65 were to be withheld and paid ratably from employee wages between January 1, 2021, until April 30, 2021. However, the Consolidated Appropriations Act, 2021, signed into law December 27, 2020, extended the period that the deferred taxes are to be withheld and paid ratably. The period is now for the entire year − from January 1, 2021, through December 31, 2021. Penalties, interest and additions to tax will now start to apply on January 1, 2022, for any unpaid balances. Notice 2021-11 makes changes to Notice 2020-65 to reflect this extended period.