How Are Employment Taxes Calculated and Reported?

Employers must withhold federal income tax (FIT) and Federal Insurance Contributions Act (FICA) taxes, which include Social Security and Medicare portions, from each employee paycheck based on the employee's Form W-4 declaration and current IRS withholding tables. Social Security tax is withheld at 6.2 percent on wages up to an annual wage base (adjusted yearly for inflation), and Medicare tax is withheld at 1.45 percent on all wages with no cap. Employers also pay a matching 6.2 percent Social Security tax and 1.45 percent Medicare tax; high-income earners are subject to an additional 0.9 percent Medicare tax on wages above certain thresholds.

Employers must remit withheld amounts and their own contributions to the IRS on a schedule that depends on deposit rules, typically monthly or semi-weekly, and file Form 941 quarterly to reconcile deposits against actual withholding liability. When working with a payroll processor or accountant, confirm they are using the current W-4 version and IRS withholding tables, as outdated tables or misapplied allowances create deposit shortfalls and reconciliation mismatches that invite IRS examination.

New York State requires employers to withhold state income tax (PIT) from employee wages using state withholding tables and the employee's New York State IT-2104 form. New York also imposes a state unemployment insurance (UI) tax on the employer at a rate that varies based on the employer's experience rating and industry. New York City employers must also withhold and remit the NYC Unincorporated Business Tax (UBT) if the business is structured as a pass-through entity.

New York employers file Form NYS-45 quarterly, due by the last day of the month following the quarter, and reconcile annually on Form NYS-AU. Failure to file the state return or remit state withholding creates a state tax lien, wage garnishment, and potential criminal referral for willful non-payment. State penalties for late deposits or filings run from 5 to 25 percent of the unpaid tax, plus interest compounding daily.

A frequent compliance gap occurs when a business owner pays federal employment taxes but delays or skips state remittance. New York State treats employment tax evasion as a felony under certain circumstances, and the state has aggressive collection authority, including asset seizure and criminal prosecution. If your business operates in multiple states, you must register and remit employment taxes in each state where you have employees.

Gross wages subject to employment tax include all compensation: salary, hourly wages, bonuses, commissions, and taxable fringe benefits. Some items are excluded from employment tax, such as bona fide business expense reimbursements, certain educational assistance under IRC Section 127, and health insurance premiums paid on behalf of the employee. Misclassifying a fringe benefit as non-taxable when it should be taxable results in under-withholding and creates a wage and hour liability.

Pre-tax deductions include health insurance premiums, 401(k) contributions, and dependent care contributions, which reduce federal income tax withholding and FICA tax. Post-tax deductions include garnishments and charitable contributions, which do not reduce employment tax and must be taken after employment tax is calculated. At year-end, employers file Form W-2 for each employee, reporting total wages and all withholding by category. The W-2 must be filed with the Social Security Administration by January 31 and provided to the employee by the same date.

Employers must distinguish between employees and independent contractors: employees trigger employment tax obligations, while contractors do not. The IRS uses a three-part test examining behavioral control, financial control, and the relationship of the parties. Misclassifying an employee as a contractor to avoid employment taxes is a common violation that triggers back employment taxes, penalties, and interest when discovered.

If you engage individuals as contractors, issue Form 1099-NEC reporting payments of $600 or more annually to each contractor and file the forms with the IRS by January 31. If you direct when and where a person works, provide equipment or training, and intend a long-term relationship, that person is likely an employee. Obtain a signed independent contractor agreement and maintain it in your records to demonstrate the intent at the time of engagement.

At the end of each quarter, compare total deposits you made to the liability shown on Form 941 (federal) or Form NYS-45 (state). If deposits fall short, you owe the difference by the return due date. If you discover an error after filing a quarterly return, you may file an amended Form 941-X (federal) or amended Form NYS-45 (state) within three years of the original filing to correct wage, withholding, or deposit amounts.

When the IRS or New York State audits your employment tax account, the examiner will request payroll records, bank statements, deposit confirmations, and W-2s to verify that all wages were reported and all taxes were withheld and deposited on time. Your defense depends on the completeness and accuracy of your records. Maintain a payroll audit file containing copies of all Forms 941, W-2s, 1099s, deposit confirmations, and payroll registers for each year. If audited, provide this file to the examiner promptly.

Employment tax compliance requires precision in calculation, timely deposits, accurate reporting, and thorough record retention. A single misclassification or missed deposit can cascade into multiple audit exposures and penalties. Your payroll system, whether in-house or outsourced, must be audited regularly to catch errors before they compound. If you are uncertain about your withholding obligations, deposit schedule, or state requirements, consult a tax professional or accountant who specializes in employment and compensation matters to conduct a compliance review. For additional guidance on related tax and employment matters, see our overview of self-employment taxes.