You would need to give your nanny a W-2, get an EIN and file Schedule H for your payments. All of this will be done for 2019.
You can apply for an EIN online. https://www.irs.gov/businesses/small-businesses-self-employed/apply-for-an-employer-identification-n....
Here is a quick breakdown: If you paid your nanny $2,100 or more in 2019, you should withhold and pay Social Security and Medicare on all of her wages. If you paid your nanny $1,000 or more in a quarter in 2019, you must pay the federal unemployment tax, or FUTA. (You may also owe state unemployment taxes.)
Generally, for 2019, an employer needs to pay Social Security and Medicare taxes for “cash wages” of $2,100 or more paid to any one employee. Cash wages refer to checks, money orders and the like. They don’t include “the value of food, lodging, clothing, transit passes and other noncash items you give your household employee.” But cash given to an employee in place of those items counts as cash wage.
Don’t count wages paid to your spouse or your child under 21, the IRS says. Wages paid to your parent typically don’t apply, either, although there are exceptions.
Don’t count wages paid to an employee under 18 at any time during the year, unless providing household services is “the employee’s principal occupation,” the IRS says.
