Tax forms 101: The forms you need to file your 2018 income taxes

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In a Nutshell

First-time filers may ask, “What tax forms do I need to file my taxes?” This year, expected major changes to Form 1040 may have veteran filers and even tax professionals asking the same question. Here’s a rundown of forms you’ll likely need to file your 2018 federal tax return.

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The days of wondering if you should use form 1040, 1040A or 1040EZ to file your taxes are over.

For the 2018 tax year and beyond, a single 1040 replaces the three forms with one version that appears much smaller than the old 1040s.

The new Form 1040 does contain fewer boxes to fill in. But that’s because many of the lines from the old 1040A and 1040 have been moved off the main form and onto additional schedules. So it’s possible that taxpayers may find they need to include even more forms with their tax returns from now on.

Since you probably still need to submit additional paperwork to the IRS, the answer to the question “What tax forms do I need?” still doesn’t have an easy answer.


What tax forms do I need to file my taxes?

First and foremost, all individuals who must file income taxes will need to submit Form 1040. In fact, the full name for Form 1040 is the U.S. Individual Income Tax Return — so when people talk about their “tax returns,” this is the form they’re referring to.

The new Form 1040 includes all your basic information.

  • Your full name and, if submitting a joint return, your spouse’s full name
  • Your address
  • Your Social Security number and your spouse’s, if applicable
  • Your filing status (single, married filing jointly, married filing separately, head of household, qualifying widow(er))
  • Whether you can be claimed as a dependent
  • Dependents you’re claiming
  • Healthcare coverage
  • Information on income from all sources
  • Whether you’re taking the standard deduction or itemizing
  • Qualified business income deduction
  • Taxes you’ve already paid
  • The amount you owe or the refund you’re entitled to
  • Whether you’re claiming the child tax credit

When you look closely at the new 1040, you’ll notice that the IRS asks you to attach additional forms and schedules. These contain information from the old 1040 and 1040A that the IRS has moved to new forms with new names.

Additional forms and schedules the IRS wants you to submit

In all fairness to the not-so-simple, new, shorter version of the 1040, most taxpayers had to submit additional forms with the old versions of the 1040, too. Even people who filed Form 1040EZ (the simplest version of the old 1040s) had to at least attach documents that showed their income.

Forms that have always been around

Forms you may need to submit with your return include the following:

  • W-2s: These are forms your employer provides detailing wages and taxable benefits earned and taxes withheld during the year. Employers must send a W-2 by January 31 if you earned more than $600 in wages during the year.
  • W-2G: This details gambling winnings and federal tax withheld from winnings.
  • 1099-MISC: If you have income from freelance or gig work, the company that paid you (at least $600) should send you a 1099 detailing the payment.

These forms typically show earned income. Of course, there are other forms you may need to include, but these are some of the most common.

If you submit a return via mail, you can attach copies of these forms. If you e-file using an online tax program, you’ll need to upload your forms to the program.

FAST FACTS

How does my employer know how much tax to withhold?

Your employer uses information you provide on your W-4, along with withholding tables and directions from the IRS, to determine how much tax to hold back from your paychecks. You can adjust your W-4 withholdings to pay more tax if you want to avoid a big tax bill and possibly increase your refund, or less tax if you want to keep as much money in your pocket as possible throughout the year.

Learn more about how to fill out a W-4.

New forms you may need to submit

Unsurprisingly, the postcard-size 1040 form doesn’t really provide the IRS with all the information necessary to determine how much tax you owe. You might also need to include schedules that provide the IRS with information about credits, deductions and income sources.

These include but aren’t limited to …

  • Schedule 1: On Schedule 1, you’ll provide information on additional sources of nonwage taxable income not reported on a W-2. This includes tax refunds, alimony, business income or loss, capital gains, rental income and unemployment compensation. You’ll also detail adjustments to income, including moving expenses (but only if you’re in the military), health savings account deductions, student loan interest deductions and IRA deductions. Schedule 1 lists multiple additional forms to attach if you have certain sources of income or claim certain deductions.
  • Schedule 2: If you’re subject to the alternative minimum tax, you’ll attach this to your Form 1040.
  • Schedule 3: This needs to be included if you’re claiming certain credits, such as the foreign tax credit, a credit for child care and dependent care expenses, education credits, credits for contributions to retirement accounts or residential energy credits. It also details more forms to submit depending on additional credits you want to claim.
  • Schedule 4: Here, you’ll include information on self-employment tax, unreported Social Security and Medicare taxes, taxes on retirement plans, and household employment taxes, along with certain additional taxes. Again, there are more forms you’ll need to include with Schedule 4, including Schedule SE if you’re self-employed and must report self-employment tax, and Schedule H if you have household employment taxes to report.
  • Schedule 5: You’ll include information on any estimated tax payments on this form, along with other details like credits for federal tax on fuels or taxes you paid along with a request to extend your time to file. And you’ll need to include this schedule, along with Form 8885, to claim the Health Coverage Tax Credit if you have a qualifying health insurance.
  • Schedule A: This is the schedule that people who itemize deductions have always had to submit. You’ll provide information on medical and dental expenses, state and local taxes, mortgage interest, student loan interest, charitable gifts and additional deductions — along with more forms. The 2018 version of this schedule is similar to the 2017 version with a few exceptions. It now specifies casualty and theft losses from federally declared disasters and eliminates job expenses and miscellaneous deductions.

Your head may be swimming with all of these add-ons to the basic 1040 form — especially since each schedule lists its own additional forms to include. Credit Karma Tax® can help you determine which additional forms you need to complete based on the deductions and credits you claim, as well as on your income sources.

Learn how to use Credit Karma Tax®

You’ll need to gather your paperwork before you file

Many of the forms you’ll need when you file your taxes are sent to you by others.

For example, you’ll receive forms from your employer or companies you did contract work for, from your student loan lender or mortgage lender detailing interest you paid, and from your health insurer specifying whether you have qualifying coverage to avoid a tax penalty. You may also receive bank account statements that show interest income, dividend statements and other types of unearned income that you need to report.

You’ll want to get all these forms together before filing your return. This way,  you’ll have the information you need to complete your 1040 form, as well as the different schedules you’re required to include.

You’ll also need last year’s tax return when preparing this year’s, because the IRS will ask for information from it. For example, your previous year’s adjusted gross income (or AGI) is used to verify your identity.

Your state may also require you to submit forms

The federal government isn’t the only government that taxes you — or that requires you to submit forms. If you live in a state with an individual income tax and you’re required to file, your state will have its own rules regarding paperwork you must submit when you file your state taxes.

The Federation of Tax Administrators has links to appropriate state tax forms for each of the 50 states plus Washington, D.C.

Learn about filing state taxes in multiple states

Bottom line

The 2018 tax year was the first in which all individual taxpayers used the new Form 1040. But a shorter, simpler 1040 doesn’t necessarily mean less paperwork for all taxpayers. Many will likely find they still have a lot of extra paperwork that must accompany their 1040.