The IRS 226-J is a letter from the IRS to the non-compliant employer that explains the consequences of the non-compliance. It explains the penalty with a detailed summary table itemizing the amount of the penalty and the proposed payment per month. It also contains a response form (Form 14764), an Employee Premium Tax Credit Listing, and a description of the actions the employer should take.
In addition, the letter gives a description of the actions the IRS will take if the employer does not respond in a timely manner.