What Is Schedule 4 Tax Form and Who Needs to File It?
Learn what the Schedule 4 tax form is, who needs to file it, and how it fits into your overall tax return to report additional taxes accurately.
The Schedule 4 tax form was used in previous years to report additional taxes, such as self-employment tax and other obligations. Starting in 2019, the IRS eliminated Schedule 4 and incorporated its components into Form 1040 and related schedules.
Understanding its past purpose helps taxpayers see how similar tax liabilities are reported today.
Who Must File
Before its removal, Schedule 4 applied to taxpayers who owed taxes beyond standard income tax. One common reason for filing was self-employment tax, which covers Social Security and Medicare contributions for individuals who work for themselves. Those earning $400 or more in net self-employment income had to report this tax, currently 15.3%—split between Social Security (12.4%) and Medicare (2.9%). Unlike employees, who share this cost with their employer, self-employed individuals pay the full amount.
Another affected group was high-income earners subject to the Net Investment Income Tax (NIIT), a 3.8% tax on capital gains, dividends, and rental income. This tax applies to single filers with modified adjusted gross income (MAGI) over $200,000 and married joint filers exceeding $250,000.
Taxpayers who owed additional Medicare tax also used Schedule 4. This 0.9% surtax applies to wages, compensation, and self-employment income above $200,000 for single filers and $250,000 for married joint filers. Unlike regular Medicare tax, this additional amount is not shared with an employer, so self-employed individuals cover the full cost.
Distinct Components
Schedule 4 consolidated various tax obligations outside standard income tax calculations. It included penalties on early withdrawals from IRAs, 401(k)s, and other retirement accounts. Unless an exception applied, early withdrawals faced a 10% penalty in addition to regular income tax.
It also covered the repayment of the Premium Tax Credit (PTC), which helps lower-income individuals afford health insurance through the Marketplace. If a taxpayer’s actual income exceeded the estimate used for advance credit payments, they had to repay some or all of the excess. Full repayment was required if income exceeded 400% of the federal poverty level.
Household employment taxes were another component. Individuals who hired household workers, such as nannies or caregivers, and paid them above a certain threshold were responsible for Social Security, Medicare, and unemployment taxes. These obligations, sometimes called the “nanny tax,” required careful record-keeping and compliance with federal and state regulations.
Where to Submit
When Schedule 4 was in use, it was filed with Form 1040 to account for additional tax liabilities. Since its elimination, these obligations are now reported on Schedule 2 or other sections of Form 1040. This change was part of an IRS effort to simplify tax filings while maintaining detailed reporting.
For electronic filers, tax software integrates these calculations into the appropriate sections, reducing errors. The IRS encourages e-filing for accuracy, faster processing, and quicker refunds. Paper filers must ensure all necessary schedules and worksheets are included to avoid delays or IRS notices.