As a Household Employer, you must keep all your records on your household employee's income and employment taxes, including Social Security, Medicare, federal unemployment taxes, federal income tax withholding, and advance payment of earned income credit, for at least 4 years after the due date of the return or after the tax is paid, whichever is later. Your records should contain:
Your employer identification number; (EIN)
Copies of returns you have filed;
Dates and amounts of any deposits or payments you made;
Each household employee's name, address, and Social Security number;
Dates each nanny was employed;
Copies of each household employee's withholding allowance certificate; (Form W-4)
Copies of each household employee's Form W-5 (if any);
Amount of Social Security and Medicare taxes collected for each pay period and the date collected; and
The reasons why the wage payment and amounts subject to FICA, FUTA, or federal income tax withholding are not equal, if applicable.