Dear Savvy Senior: What are the IRS income tax filing requirements for seniors this year? I didn’t file a tax return the past two years because my income was below the filing requirements, but I got a part-time job late last year, so I’m wondering if I’m required to file. — Part-time Retiree

Dear Part-time: Whether or not you are required to file a federal income tax return this year will depend on how much you earned in 2017, the source of that income, your age and your filing status.

Here’s a rundown of this tax season’s IRS tax filing requirement thresholds.

For most people, this is pretty straightforward. If your 2017 gross income — which includes all taxable income, not counting your Social Security benefits, unless you are married and filing separately — was below the threshold for your filing status and age, you probably won’t have to file. But if it’s over, you will.

>> Single: $10,400 ($11,950 if you’re 65 or older by Jan. 1, 2018).

>> Married filing jointly: $20,800 ($22,050 if you or your spouse is 65 or older; or $23,300 if you’re both over 65).

>> Married filing separately: $4,050 at any age.

>> Head of household: $13,400 ($14,950 if age 65 or older).

>> Qualifying widow(er) with dependent child: $16,750 ($18,000 if age 65 or older).

To get a detailed breakdown on federal filing requirements, along with information on taxable and nontaxable income, call the IRS at 800-829-3676 and ask them to mail you a free copy of the “Tax Guide for Seniors” (publication 554), or see IRS.gov/pub/irs-pdf/p554.pdf.

There are other financial situations that can require you to file a tax return, even if your income falls below the filing requirement. For example, if you had earnings from self-employment in 2017 of $400 or more, or if you’re receiving Social Security benefits and half your benefits plus all other income, including tax-exempt interest, exceeds $25,000 (or $32,000 if you are married filing jointly), you’ll probably need to file.

To figure this out, the IRS offers an interactive tax assistant tool on its website that asks a series of questions to help you determine if you’re required to file, or if you should file because you’re due a refund.

Access this tool at IRS.gov/filing and click on the “Do I Need to File?” button. Or call the IRS helpline at 800-829-1040. You can also get face-to-face help at a Taxpayer Assistance Center. See IRS.gov/localcontacts or call 800-829-1040 to locate a center near you.

Even if you’re not required to file a federal tax return this year, don’t assume that you’re excused from filing state income taxes. State rules differ; see Taxadmin.org/state-tax-agencies.

If you do need to file a tax return, you can get help through the Tax Counseling for the Elderly program, sponsored by the IRS. This program provides free tax preparation and counseling to middle and low-income taxpayers, age 60 and older. Call 800-906-9887 or visit IRS.treasury.gov/freetaxprep.

Also check with AARP for free tax preparation. Call 888-227-7669 or visit AARP.org/findtaxhelp. You don’t have to be an AARP member to use this service.