1. Obtain an EIN (Employer Identification Number) at IRS.gov. The EIN is used on Federal and state tax filings for businesses including payroll tax reports.
2. Employees complete IRS form W-4 form and I-9. The I-9 is used to verify the identity and employment authorization of individuals. The W-4 form is used to indicate the amount of federal income tax withholding. Also there are state withholding forms specific to your state, the M-4 for Massachusetts, W-4ME for Maine, RI W-4 for Rhode Island.
3. Obtain Workers comp Insurance

A payroll company can perform many of the tasks required to process payroll timely and accurately including calculating correct tax withholdings and benefits payments. A payroll company can directly deposit your employees pay into their bank accounts, pay the payroll tax due and file payroll tax returns and W-2 forms at the end of the year.