What Schedule 4 Is For

Schedule 4 (Form 1040) is a supplemental form used to report "Other Taxes" that can't be entered directly on your main Form 1040. It was introduced as part of the 2018 Form 1040 redesign, which replaced Forms 1040A and 1040EZ with a streamlined base Form 1040 plus six numbered schedules. Schedule 4 specifically handles the additional taxes that previously appeared in the "Other Taxes" section of the old 2017 Form 1040.

Think of Schedule 4 as the catch-all form for taxes beyond regular income tax. It captures a range of special-situation taxes, including self-employment tax, penalties on retirement account distributions, household employment taxes, healthcare-related payments, and various recapture taxes. You'll only need to file this schedule if one or more of these special taxes applies to your situation—many taxpayers won't need it at all. IRS.gov

When You'd Use Schedule 4 (Including Late or Amended Returns)

You must attach Schedule 4 to your 2018 Form 1040 if you owe any of the following taxes:

• Self-employment tax (if you had net earnings from self-employment of $400 or more)
• Unreported Social Security and Medicare tax on tips or wages your employer didn't withhold
• Additional tax on early withdrawals from IRAs or other retirement accounts
• Household employment taxes (if you paid a household employee like a nanny or housekeeper)
• Repayment of the first-time homebuyer credit from 2008
• Health care individual responsibility payment (if you, your spouse, or dependents lacked minimum essential health coverage for part of 2018)
• Various "other taxes" including recapture of certain tax credits, additional taxes on Health Savings Accounts (HSAs), and more

Filing Deadline

For 2018 tax returns, the original deadline was April 15, 2019 (April 17, 2019 for Maine and Massachusetts residents due to state holidays). If you missed the deadline, you can still file a late return, though penalties and interest may apply.

Amended Returns

If you discover after filing that you owed a tax that should have been reported on Schedule 4, you'll need to file Form 1040-X (Amended U.S. Individual Income Tax Return) and attach the corrected Schedule 4. The IRS allows you to amend returns within three years of the original due date or within two years of paying the tax, whichever is later. IRS.gov

Key Rules for 2018

Health Care Individual Responsibility Payment

For 2018, the individual mandate penalty still applied. If you or your dependents didn't have minimum essential health coverage or a coverage exemption for any month in 2018, you generally owed a shared responsibility payment reported on Schedule 4, line 61. (Note: This penalty was eliminated starting in 2019.)

Self-Employment Tax Threshold

If you were self-employed with net earnings of $400 or more, you were required to calculate self-employment tax using Schedule SE and report it on Schedule 4, line 57.

Household Employment Threshold

You owed household employment taxes if you paid any one household employee cash wages of $2,100 or more in 2018, or if you paid total cash wages of $1,000 or more in any calendar quarter of 2017 or 2018.

Retirement Account Penalties

Early distributions from retirement accounts (before age 59½) typically triggered a 10% additional tax unless you qualified for an exception. This tax was reported on line 59.

First-Time Homebuyer Credit Repayment

If you claimed the first-time homebuyer credit for a home purchased in 2008, you were required to repay 1/15th of the credit each year for 15 years, reported on line 60b—unless you qualified for an exception.

Tip Reporting Penalty

If you received tips of $20 or more in any month but didn't report the full amount to your employer, you not only owed the Social Security and Medicare tax on those tips but could also face a penalty equal to 50% of the tax due. IRS.gov

Step-by-Step (High Level)

Step 1: Determine if You Need Schedule 4

Review your tax situation against the list of "other taxes." If none apply, you don't need to file this schedule.

Step 2: Gather Supporting Forms

Depending on which taxes you owe, collect the necessary forms:

• Schedule SE for self-employment tax
• Forms 4137 or 8919 for unreported Social Security/Medicare tax
• Form 5329 for additional tax on retirement accounts
• Schedule H for household employment taxes
• Form 5405 for homebuyer credit repayment
• Form 8965 for health coverage exemptions

Step 3: Complete the Supporting Forms First

Fill out each applicable supporting form according to its instructions. These forms will calculate the specific tax amounts you'll transfer to Schedule 4.

Step 4: Transfer Amounts to Schedule 4

Enter the calculated tax amounts on the appropriate lines (57-62). For line 62 ("Other Taxes"), make sure to check the correct box and enter the proper code identifying the tax type.

Step 5: Total Your Other Taxes

Add all amounts entered on lines 57 through 62 and enter the total on line 64. This is your total other taxes.

Step 6: Transfer to Form 1040

Copy the line 64 total to Form 1040, line 14. This integrates your other taxes into your overall tax liability.

Step 7: Attach Everything

Attach Schedule 4 and all supporting forms (Schedule SE, Form 5329, Schedule H, etc.) to your Form 1040 before mailing or e-filing. IRS.gov

Common Mistakes and How to Avoid Them

Mistake #1: Not Attaching Required Forms

Many Schedule 4 lines require you to attach supporting forms like Schedule SE, Form 5329, or Schedule H. Simply entering a number isn't enough—you must include the backup documentation. Solution: Create a checklist of which forms need to be attached for your specific situation before sealing the envelope or submitting electronically.

Mistake #2: Including Noncash Tips in Form 4137

When calculating unreported tip tax, taxpayers sometimes include noncash tips like tickets, passes, or other property. Solution: Only report cash tips (including those paid by check or money order) on Form 4137. Noncash tips aren't subject to Social Security and Medicare taxes.

Mistake #3: Ignoring the 10% Early Distribution Exception

If you took an early distribution from a retirement account and received Form 1099-R with distribution code 1 in box 7, you might be able to skip Form 5329 and simply multiply the taxable amount by 10%. However, taxpayers often file Form 5329 unnecessarily. Solution: Check if distribution code 1 is correctly shown on all your Forms 1099-R. If so, you can calculate the 10% tax directly and write "No" next to line 59. Only file Form 5329 if the code is incorrect or you qualify for an exception.

Mistake #4: Missing Health Coverage Exemptions

Some taxpayers pay the full individual responsibility payment without checking if they qualify for exemptions (such as for financial hardship, short coverage gaps, or income below the filing threshold). Solution: Always complete Form 8965 to see if you qualify for any exemptions before calculating the shared responsibility payment for line 61.

Mistake #5: Forgetting to Enter Tax Codes on Line 62

Line 62 covers various "other taxes," each requiring a specific code (like "HSA" for Health Savings Account tax or "UT" for uncollected Social Security tax). Failing to include the code creates processing delays. Solution: Carefully review the line 62 instructions for your specific tax type and enter both the amount and the proper identifying code.

Mistake #6: Not Keeping Documentation

Taxpayers sometimes discard Forms 1095-A, 1095-B, or 1095-C thinking they're not important. While you don't attach them to your return, they contain information needed for completing line 61. Solution: Keep these forms with your tax records even though you don't submit them with your return. IRS.gov

What Happens After You File

Processing Time

Once you submit your return with Schedule 4, the IRS typically processes it within 21 days if you e-file with direct deposit, or 6-8 weeks if you mail a paper return. However, returns claiming certain credits or reporting complex taxes may take longer to review.

Verification and Audits

Because Schedule 4 reports self-calculated taxes (like self-employment tax or retirement account penalties), the IRS may compare your figures against third-party reporting (like Forms 1099-R, W-2, or 1099-NEC). Discrepancies can trigger correspondence or an audit request.

Payment Requirements

If Schedule 4 increases your overall tax liability beyond what you've already paid through withholding and estimated payments, you'll owe the balance when you file. The IRS charges interest on unpaid taxes from the original due date, plus potential late-payment penalties if you don't pay by the deadline.

Future Year Implications

Some Schedule 4 taxes are ongoing obligations. For example, if you're self-employed, you'll likely need to file Schedule SE (and therefore Schedule 4) every year. If you're repaying the homebuyer credit, you'll report it annually on Schedule 4 for 15 years. The health coverage exemptions and calculations for 2018 don't carry over to 2019, when the individual mandate penalty was eliminated.

Amended Return Processing

If you file Form 1040-X to add or correct Schedule 4, expect a longer processing time—typically 8 to 12 weeks, though it can take up to 16 weeks during busy periods. The IRS will mail you an explanation of any changes they make to your return. IRS.gov

FAQs

Q1: Do I need to file Schedule 4 if I only had wages from a W-2?

Generally, no. If you were a traditional employee with only W-2 income and had health coverage all year, you probably won't need Schedule 4. However, there are exceptions—for example, if your employer didn't withhold Social Security and Medicare taxes, or if you had a household employee you paid more than the threshold amounts, you'd need Schedule 4.

Q2: What's the difference between Form 1040, line 14 and Schedule 4?

Form 1040, line 14 is where your total "other taxes" appear on your main tax return. Schedule 4 is the detailed worksheet that breaks down what makes up that total. Think of line 14 as the summary and Schedule 4 as the detailed explanation you attach to support it.

Q3: Can I e-file with Schedule 4, or do I have to mail a paper return?

You can absolutely e-file with Schedule 4. Tax software will automatically include Schedule 4 if you answer questions that trigger any of these other taxes. The software will also help you complete the required supporting forms like Schedule SE or Form 5329.

Q4: I had health insurance all year but didn't check the coverage box on Form 1040. Do I need to amend my return?

If you had minimum essential coverage for the entire year, you should have checked the "Full-year health care coverage or exempt" box on page 1 of Form 1040. If you forgot to check it but legitimately had coverage, you may want to file an amended return to avoid potential IRS questions, though forgetting to check the box alone doesn't necessarily mean you owe a penalty if you actually had coverage.

Q5: I'm self-employed. Do I always need Schedule 4?

If your net self-employment earnings were $400 or more, yes—you'll need to calculate self-employment tax on Schedule SE and report it on Schedule 4, line 57. This is true even if your total tax liability ends up being zero due to other credits and deductions.

Q6: How long do I have to repay the first-time homebuyer credit?

For homes purchased in 2008, the credit must be repaid over 15 years (1/15th each year) unless you qualify for an exception. This means you'd report the repayment on Schedule 4, line 60b for the 2018 tax year and would continue reporting it annually through 2022 (15 years from 2008). Exceptions include selling the home, no longer using it as your main home, or death.

Q7: What if I can't pay the taxes shown on Schedule 4?

If you can't pay the full amount, you should still file your return on time to avoid late-filing penalties (which are steeper than late-payment penalties). Then contact the IRS to set up a payment plan or installment agreement. You can apply online at IRS.gov/payments or call the number on your tax bill. Interest and late-payment penalties will still accrue, but you'll avoid the more severe failure-to-file penalty. IRS.gov

This guide is based on official IRS instructions and publications available at IRS.gov. For the most current information and to access the actual 2018 forms, visit IRS.gov/Form1040 or search for "2018 Schedule 4" at IRS.gov/PriorYear.