How to Fill Out Michigan Form 5118 (w/Examples) + FAQs

Michigan Form 5118 is the City of Detroit Resident Income Tax Return that every full-year Detroit resident must file with the Michigan Department of Treasury when they have taxable income, regardless of where they earned it. The form reports wages, business income, interest, and other income to the City of Detroit, calculates the 2.4% resident tax rate, and reconciles withholding shown on each W-2 box 19.

Filing the wrong city form, skipping the City Schedule W, or missing the April 15 deadline triggers interest at 1% per month and penalties up to 25% of unpaid tax under the City Income Tax Act, MCL 141.664. The Treasury processes more than 200,000 Detroit individual returns each year, and roughly 1 in 7 paper filings get bounced back for missing schedules or wage mismatches according to the agency’s Detroit City Tax page.

In this guide, you will learn:

• 📝 How to complete every line and box on Form 5118 with named examples
• 🧾 Which attachments, W-2 codes, and schedules must travel with your return
• 💻 How to file through Michigan Treasury Online (MTO), tax software, or paper mail
• ⚠️ The most common Detroit-specific mistakes and the penalties they trigger
• ❓ Field-level FAQs that answer the questions Detroit residents actually ask

What Form 5118 Is and Who Must File It

Form 5118 is the annual income tax return for people who lived inside the City of Detroit for the entire tax year. The City of Detroit imposes a 2.4% resident income tax under the City Income Tax Act, and the Michigan Department of Treasury has administered Detroit’s individual income tax since 2017 under the agreement found on the Detroit City Tax administration page. The form replaces the older D-1040(R) that Detroit residents used before the state takeover.

You must file Form 5118 if you lived in Detroit for all 12 months of the tax year and your gross income exceeds your total exemption allowance. Part-year residents file Form 5120 instead, and nonresidents who only worked in Detroit file Form 5119. A resident who works in Detroit pays the full 2.4%, while a resident who works in another taxing city like Grand Rapids or Highland Park can claim a credit on the Schedule TC.

The form is required even if your only income is wages and your employer already withheld Detroit tax shown in box 19 of your W-2. The withholding is treated as a deposit, not a final payment, and you still must reconcile it on the return. Detroit residents who fail to file face a failure-to-file penalty of 5% per month up to 25% under MCL 141.664, plus interest tied to the adjusted prime rate published by Treasury.

A common misconception is that Detroit tax only applies to people who work in Detroit. Residency, not work location, drives the obligation, so a Detroit resident who commutes to Troy or Southfield still owes the full resident rate on every dollar of wages, even though Troy does not have a city income tax.

Before You Start: Documents and Information You Need

Pull every document below before you open the form. Treasury rejects roughly 14% of paper Detroit returns for missing wage statements or schedules, based on processing notes published with the City of Detroit individual income tax instructions. Gathering everything first prevents a return-to-sender letter that can delay your refund by 8 to 12 weeks.

• Federal Form 1040 for the same tax year, because Form 5118 starts with federal AGI on Line 10. Without it, you cannot complete Line 10 accurately.
• All W-2s for you and your spouse, especially boxes 5, 18, 19, and 20. Box 20 must read DETROIT for any Detroit withholding to count, and a missing W-2 stalls the City Schedule W reconciliation.
• All 1099-NEC, 1099-MISC, 1099-INT, 1099-DIV, and 1099-R forms. Detroit taxes business and interest income for residents, so omitting a 1099 understates Line 11 and Line 12.
• Federal Schedule C, E, or F if you have self-employment, rental, or farm income, because the net amounts feed into Line 11 of Form 5118.
• Last year’s Form 5118 to confirm carryforwards, prior overpayments applied, and your filing status history.
• Social Security numbers for you, your spouse, and every dependent. A mismatch with SSA records puts the return on a manual review queue.
• Detroit street address with full ZIP+4, because P.O. boxes alone do not prove residency for Detroit’s domicile rules.
• Bank routing and account numbers if you want direct deposit of your refund or a direct debit of a balance due.
• Form 5121 (City Schedule W), the wage reconciliation schedule that lists every W-2 with Detroit withholding.
• Schedule TC if you paid tax to another Michigan taxing city, plus a copy of that city’s return as proof of credit.

Where to Get the Form and How to Access It

The official current-year Form 5118 lives on the Michigan Treasury City Tax Forms page, where Treasury posts the fillable PDF, the line-by-line instructions, and any mid-year revisions. Always pull the form fresh each year, because Treasury updates the revision date stamped in the lower-left corner of page 1, and using last year’s PDF can produce the wrong tax rate or exemption amount.

You can also access Form 5118 inside most major tax software, including TurboTax, H&R Block, FreeTaxUSA, and TaxAct. The software pulls federal AGI directly into Line 10 and auto-builds the City Schedule W from imported W-2s. The 2025 tax-year revision date stamped on the bottom of the form is 09-25, and that is the version filed during the 2026 filing season.

Detroit residents who qualify for Free File through Michigan Treasury can file Form 5118 at no cost if their federal AGI is at or below the published threshold, which is typically updated each January. Paper copies are also available at the Coleman A. Young Municipal Center finance counter and at most Detroit Public Library branches during tax season.

A nuance many filers miss is that the fillable PDF on Treasury’s site has built-in math but does not e-file by itself. To submit electronically, the return must travel through MTO or an approved software vendor listed on the Treasury approved e-file vendors page.

Step-by-Step: How to Fill Out Form 5118 Line by Line

The form is two pages with a header block, a filing-status block, an exemptions block, an income block, a tax-and-credits block, a payments block, and a signature block. Work top to bottom, page 1 first, because page 2’s tax calculation depends on figures from page 1. Italicized text below shows what a real filer writes on the form.

Filer Name and Social Security Number

This field asks for your full legal name and SSN exactly as shown on your Social Security card. Enter last name first, then first name, then middle initial, all in capital letters with no punctuation. Carlos M. Reyes writes REYES CARLOS M in the name box and 123-45-6789 in the SSN box.

If you changed your name during the year through marriage or court order, use the name now on file with the SSA, not the name on last year’s return. The agency cross-checks the SSN against SSA records, and a mismatch triggers a freeze that stops refund processing until you mail in proof. The most common mistake here is writing a nickname like Charlie instead of the legal Charles, which causes the return to fall out of the automated match. A misconception is that Treasury can pull the corrected name from your federal return — it cannot, because Detroit returns are processed on a separate system.

Spouse Name and Social Security Number

The spouse fields appear immediately below the primary filer block and must be completed for any Married Filing Jointly return. Enter the spouse’s legal name in the same LAST FIRST MIDDLE format and the spouse’s SSN in 999-99-9999 form. Aisha Reyes writes REYES AISHA L and 987-65-4321.

If you are filing Married Filing Separately, leave this block blank and check the MFS box in the filing status section, but you still must list the spouse’s SSN further down the form. A missing spouse SSN on a joint return drops the return into manual review and delays processing by about 6 weeks. The misconception that you can simply combine names like CARLOS AND AISHA REYES into the primary line will cause the return to be rejected for an unreadable SSN match.

Home Address (Street, City, State, ZIP)

This field captures the Detroit street address you lived at on December 31 of the tax year. Write the number and street on one line, with apartment number after a comma, then DETROIT, MI and the full ZIP+4. Carlos writes 4821 W GRAND BLVD APT 3B, DETROIT, MI 48208-1142.

If you moved within Detroit during the year, use the December 31 address only — the form has a separate box for prior addresses if Treasury requests them. A P.O. box alone is not acceptable because Detroit’s domicile test requires a physical residence inside city limits. The most common mistake is entering a suburban mailing address used for forwarded mail; that turns the return into a part-year filing and triggers a notice asking you to refile on Form 5120. The misconception that “ZIP code 482xx means Detroit” is wrong — ZIP codes like 48203 and 48212 cross into Highland Park and Hamtramck, which have separate city taxes.

Filing Status (Boxes a, b, c, d)

Form 5118 lists four filing statuses: Single (a), Married Filing Jointly (b), Married Filing Separately (c), and Head of Household — Single (d, treated as single by Detroit). Check exactly one box. Carlos and Aisha Reyes check box (b) Married Filing Jointly.

Your Detroit filing status normally mirrors your federal status, but Detroit does not recognize a separate Head of Household rate, so HoH filers check box (d). If both spouses are Detroit residents, MFJ is almost always cheaper because of the doubled exemption allowance. The most common error is checking MFJ when only one spouse lived in Detroit; in that case the resident spouse should file MFS on Form 5118 and the nonresident spouse files Form 5119. The misconception that MFS saves Detroit tax is usually wrong because MFS doubles the audit risk without lowering the rate.

Residency Status

The residency block confirms that you lived in Detroit all 12 months. Check the Resident box on Form 5118 — this is the only correct status for this form. Carlos checks Resident — Full Year.

If you moved into or out of Detroit at any point during the year, stop and switch to Form 5120 (Part-Year Resident). Filing 5118 when you were only a resident for part of the year overstates your tax base by attributing nonresident income to Detroit, and Treasury will issue an assessment. The misconception that “I still owned my Detroit house, so I’m a full-year resident” ignores that domicile depends on where you actually lived and slept, not where you held property.

Exemptions (Line 9)

Line 9 multiplies the number of exemptions by the Detroit per-exemption amount, which is $600 for tax year 2025 per the Detroit individual instructions. Enter the number of personal exemptions in box 9a, the number of dependent exemptions in 9b, add them on 9c, then multiply by $600 and write the result on 9d. Carlos and Aisha with two children enter 2 in 9a, 2 in 9b, 4 in 9c, and $2,400 in 9d.

You cannot claim yourself as a dependent on someone else’s return and also claim a personal exemption on your own Form 5118; one or the other. The most common mistake is copying the federal dependent count without checking that each dependent has an SSN or ITIN on the return — a missing identifier kicks out the exemption and raises the tax owed. The misconception that Detroit follows the federal “$0 personal exemption” rule from the 2017 Tax Cuts and Jobs Act is wrong: Detroit kept its own exemption alive under the City Income Tax Act.

Line 10 — Federal Adjusted Gross Income

Line 10 asks for the AGI from your federal Form 1040, line 11. Copy that number exactly, including any negative sign for a loss year. Carlos and Aisha report federal AGI of $78,400 and write 78,400 on Line 10.

If you amended the federal return after filing, use the amended AGI and attach a copy of the federal 1040-X. The most common mistake is pulling AGI from a draft federal return that later changes during e-file review, which causes Line 10 to mismatch the IRS file Treasury cross-references. The misconception that Detroit AGI equals federal taxable income (after the standard deduction) is wrong — Detroit starts at AGI, before deductions.

Line 11 — Additions to Income

Line 11 adds back items the city taxes that the federal return does not, such as net operating loss carryovers from prior city returns, and certain pass-through losses. Enter the total from the additions worksheet in the Form 5118 instructions. Carlos has none and writes 0.

A self-employed Detroit resident with a Schedule C business operating outside the city still includes the full Schedule C net profit here if it was included in federal AGI; Detroit taxes residents on worldwide income. Forgetting to add back a prior-year city NOL that was deducted federally is a common error and produces an underpayment notice within 4 months. The misconception that “if it’s not on my federal return, Detroit can’t see it” ignores Treasury’s matching with state and federal data.

Line 12 — Subtractions from Income

Line 12 subtracts items Detroit does not tax, including interest from U.S. obligations, military pay for active-duty service members stationed outside Michigan, and qualifying retirement income for taxpayers meeting the age tests in the instructions. Enter the total from the subtractions worksheet. Aisha has $1,200 of U.S. Treasury bond interest already included in federal AGI and writes 1,200.

The Renaissance Zone deduction also flows through Line 12 if your Detroit address is inside a designated Renaissance Zone and you meet the residency test. The most common mistake is subtracting Social Security benefits — Detroit already excludes them at the federal level through AGI, so subtracting again double-dips and triggers an assessment. The misconception that “all retirement income is exempt” is wrong; only specified pension and IRA distributions qualify and only if you meet the age and source tests.

Line 13 — Total Income Subject to Tax

Line 13 equals Line 10 plus Line 11 minus Line 12. This is the city’s version of taxable-income-before-exemptions. Carlos and Aisha compute 78,400 + 0 − 1,200 = 77,200 on Line 13.

If Line 13 is negative, enter zero — Detroit does not allow a current-year loss to create a refund of withheld tax beyond the actual amount withheld. The most common error is arithmetic transposition (entering 72,700 instead of 77,200), which Treasury catches but only after a 6 to 8 week delay. The misconception that you can carry today’s negative Line 13 backward to a prior year is wrong; the city only allows forward NOL carryovers under the instructions.

Line 14 — Exemption Allowance

Line 14 simply pulls the dollar figure from Line 9d. Carlos and Aisha enter 2,400.

Double-check this number, because a single typo here changes tax due by $14.40 per missed exemption at the 2.4% rate. The most common mistake is leaving Line 14 blank when 9d is filled in, which causes the calculation to overstate tax. The misconception that the exemption amount is the same as the federal exemption is wrong — Detroit’s amount is set by city ordinance and updated each year in the instructions.

Line 15 — Total Income After Exemptions

Line 15 equals Line 13 minus Line 14, and it is the figure the 2.4% rate is applied to. Carlos and Aisha compute 77,200 − 2,400 = 74,800.

If Line 15 is negative, enter zero. The most common error is forgetting to subtract Line 14, which inflates tax by 2.4% of the exemption amount. The misconception that Detroit “rounds down” to the nearest hundred is false; enter the exact dollar amount, rounded to whole dollars.

Line 16 — Tax (Multiply Line 15 by 2.4%)

Line 16 multiplies Line 15 by 0.024. Carlos and Aisha compute 74,800 × 0.024 = 1,795.20, rounded to 1,795.

The 2.4% resident rate is set by Detroit ordinance and ratified by the City Income Tax Act, MCL 141.503. The most common mistake is using the 1.2% nonresident rate by accident, especially when filers transfer numbers from a spouse’s nonresident city return. The misconception that the rate dropped after 2017 is wrong; Detroit’s resident rate has been 2.4% since 2003.

Line 17 — Credit for Tax Paid to Another City (Schedule TC)

Line 17 reports the credit from Schedule TC for Michigan city tax paid to a different taxing city on the same income. Attach Schedule TC and a copy of the other city’s return. Janet, who lives in Detroit but worked in Grand Rapids, computes a $360 credit on Schedule TC and enters 360 on Line 17.

The credit is capped at the lesser of (a) the actual tax paid to the other city or (b) the Detroit tax that would have been due on the same income. The most common mistake is claiming the withheld amount instead of the liability amount from the other city’s return — only the actual liability counts. The misconception that you can claim a credit for state tax (Michigan MI-1040) is wrong; the credit only applies to other Michigan city income taxes.

Line 18 — Total Tax After Credits

Line 18 equals Line 16 minus Line 17. Carlos and Aisha with no Schedule TC enter 1,795; Janet enters 1,435.

If Line 18 is zero or negative, enter zero — credits cannot generate a refund on their own. The common mistake is double-counting the Schedule TC credit on both Line 17 and a separate withholding line. The misconception that Detroit allows a generic “low income credit” mirroring the state EITC is false; Detroit has no city EITC.

Line 19 — Detroit Tax Withheld (from City Schedule W)

Line 19 pulls the total from Form 5121, the City Schedule W, which lists every W-2 with Detroit tax in box 19. Attach Schedule W. Carlos and Aisha combine W-2 box 19 amounts of $1,650 and $980 for total withholding of 2,630 on Line 19.

If your employer entered Detroit withholding in box 19 but coded box 20 as anything other than DETROIT (or the IRS-assigned code), Treasury may disallow it until the W-2 is corrected. The most common mistake is listing only the primary filer’s W-2s and forgetting the spouse’s on a joint return. The misconception that you can claim an estimate of withholding without a W-2C is wrong — Treasury requires the corrected W-2 before allowing the credit.

Line 20 — Estimated Payments and Prior-Year Credit

Line 20 reports estimated tax payments made on Form 5123 during the year, plus any prior-year overpayment you elected to apply forward on last year’s Line 25. Marcus, a self-employed Detroit barber, paid four $300 estimated payments and writes 1,200.

If you forgot a quarterly payment, you cannot retroactively make it up here without triggering the underpayment penalty on Form 5338. The most common mistake is including federal estimated payments by accident, which inflates the line and causes a refund offset notice. The misconception that withholding and estimated payments are interchangeable is wrong on the form — they belong on separate lines because Treasury matches each to a different data source.

Line 21 — Total Payments

Line 21 equals Line 19 plus Line 20. Carlos and Aisha enter 2,630; Marcus enters 1,200.

A common error is entering Line 21 below Line 19 alone, dropping the estimated payments. The misconception that Treasury will “find” your missing payments through internal records is wrong; if Line 21 is short, you get a balance-due notice even if you paid.

Line 22 — Refund

If Line 21 is greater than Line 18, subtract and enter the refund on Line 22. Carlos and Aisha compute 2,630 − 1,795 = 835 on Line 22.

Refunds under $1 are not issued. The most common mistake is rushing past the direct-deposit boxes lower on the form, which forces Treasury to mail a paper check that takes 6 to 8 weeks. The misconception that Detroit refunds piggyback on the IRS direct deposit is wrong — Detroit issues its refund separately, on its own schedule.

Line 23 — Amount Owed

If Line 18 is greater than Line 21, subtract and enter the balance due on Line 23. Marcus with $1,795 of tax and $1,200 of payments enters 595 on Line 23.

Pay by the April 15 deadline to avoid 1% per month interest plus penalty under MCL 141.664. The common mistake is mailing a check without writing your SSN and “2025 Form 5118” in the memo line, which leaves Treasury unable to match the payment. The misconception that filing late but paying on time avoids penalty is wrong — both must happen on time.

Line 24 — Penalty and Interest

If Line 23 is owed and you are filing late, compute penalty and interest using the worksheet in the instructions and enter the total on Line 24. Marcus, filing 60 days late on a $595 balance, owes roughly $30 of penalty plus $12 of interest, totaling 42 on Line 24.

Treasury will compute this for you if you leave it blank, but a billing letter follows. The common mistake is using the IRS rates (which differ); always use the rates published on the Michigan Treasury interest rate page. The misconception that interest stops accruing on the filing date is wrong — it stops on the payment date.

Line 25 — Apply Refund to Next Year

Line 25 lets you apply some or all of a Line 22 refund as an estimated payment toward next year’s Detroit tax. Enter the dollar amount you want carried forward. Carlos and Aisha apply 200 to next year’s estimates and receive the remaining $635 as a refund.

The amount on Line 25 is irrevocable once the return is filed. A common mistake is applying more than Line 22, which Treasury caps at the refund amount and may delay processing. The misconception that the carryforward earns interest is wrong; it sits at zero interest until used.

Direct Deposit Boxes (Routing, Account, Type)

The direct-deposit block at the bottom of page 2 captures a 9-digit routing number, the account number, and a checkbox for Checking or Savings. Carlos and Aisha enter routing 072000326, account 1234567890, and check Checking.

Double-check the routing number against a check, not a deposit slip — deposit slips often show an internal routing number that bounces. The most common mistake is one transposed digit, which sends the refund to the wrong bank or causes Treasury to fall back to a paper check. The misconception that Detroit can re-issue an electronic deposit is wrong; once it bounces, you wait for the paper check.

Signature, Date, and Phone

The signature block requires both spouses’ signatures on a joint return, the date of signing, and a daytime phone. Sign in blue or black ink on paper; e-filed returns use a self-select PIN. Carlos signs Carlos M. Reyes 04/12/2026 313-555-0144.

An unsigned paper return is not considered filed under the City Income Tax Act, and Treasury will mail it back. The most common mistake is one spouse signing for both on a joint return, which voids the joint election. The misconception that your tax preparer’s signature replaces yours is wrong — the preparer signs in a separate paid-preparer block lower on page 2.

Three Filled-Out Examples Using Real Scenarios

Example 1 — Carlos and Aisha Reyes, MFJ Detroit Residents with Two Kids

Form Section	What Carlos and Aisha Enter
Filer name and SSN	REYES CARLOS M / 123-45-6789
Spouse name and SSN	REYES AISHA L / 987-65-4321
Address	4821 W GRAND BLVD APT 3B, DETROIT, MI 48208-1142
Filing status (Box b)	Checked — Married Filing Jointly
Line 9 exemptions	4 × $600 = $2,400
Line 10 federal AGI	$78,400
Line 13 income subject to tax	$77,200
Line 16 tax at 2.4%	$1,795
Line 19 Detroit withholding (Schedule W)	$2,630
Line 22 refund	$835

Example 2 — Janet Williams, Single Detroit Resident Working in Grand Rapids

Form Section	What Janet Enters
Filer name and SSN	WILLIAMS JANET A / 222-33-4444
Address	18204 MUIRLAND ST, DETROIT, MI 48221-2310
Filing status (Box a)	Checked — Single
Line 9 exemptions	1 × $600 = $600
Line 10 federal AGI	$62,000
Line 13 income subject to tax	$62,000
Line 15 income after exemptions	$61,400
Line 16 tax at 2.4%	$1,474
Line 17 Schedule TC credit (Grand Rapids)	$360
Line 18 tax after credits	$1,114
Line 19 Detroit withholding	$0
Line 23 balance due	$1,114

Example 3 — Marcus Johnson, Self-Employed Detroit Barber

Form Section	What Marcus Enters
Filer name and SSN	JOHNSON MARCUS T / 555-66-7777
Address	9120 LIVERNOIS AVE, DETROIT, MI 48204-2841
Filing status (Box a)	Checked — Single
Line 9 exemptions	1 × $600 = $600
Line 10 federal AGI (Schedule C net $76,500)	$75,400
Line 13 income subject to tax	$75,400
Line 15 income after exemptions	$74,800
Line 16 tax at 2.4%	$1,795
Line 19 Detroit withholding	$0
Line 20 estimated payments (Form 5123)	$1,200
Line 23 balance due	$595
Line 24 penalty and interest (60 days late)	$42

How to File the Completed Form

Detroit residents have three filing channels for Form 5118: e-file through approved tax software, e-file through Michigan Treasury Online (MTO), or paper mail to Treasury. About 87% of Detroit individual returns now arrive electronically, based on annual volume reports from the Michigan Department of Treasury annual report archive.

E-file through software is the fastest channel. The fee depends on the vendor — TurboTax, H&R Block, and TaxAct generally charge $25 to $55 for the Detroit add-on, while FreeTaxUSA and Cash App Taxes include it free. Accepted payment methods include credit card, debit card, and direct debit (ACH). Processing time is 2 to 4 weeks for refunds, and the proof of filing is the electronic acknowledgment email plus the submission ID, both of which you should save as PDFs.

E-file through MTO is free for individuals with an MTO account. There is no filing fee. Payment options inside MTO include direct debit at no cost and credit card with a 2.3% convenience fee charged by the third-party processor Official Payments / ACI. Processing time is similar to vendor e-file, and the proof of filing is the MTO confirmation page (print and save it).

Paper filing requires a printed Form 5118, Form 5121 City Schedule W, and any other supporting schedules, mailed to: Michigan Department of Treasury, Lansing, MI 48929 for refund returns or Michigan Department of Treasury, Lansing, MI 48929 for balance-due returns. Always verify the current address on the Detroit forms page. There is no filing fee, but a balance-due paper return must include a check made payable to State of Michigan — Detroit. Processing time is 8 to 12 weeks, and the proof of filing is a USPS Certified Mail receipt with tracking, kept with your tax records for at least 6 years.

What Happens After You File

Treasury sends an electronic acknowledgment within 24 to 48 hours for e-filed returns; paper filers get no acknowledgment until the refund or notice is issued. You can track refund status on Treasury’s “Where’s My Refund?” tool using your SSN, filing status, and the refund amount.

If Treasury finds an issue, you receive a Letter of Inquiry, an Adjustment Notice, or a full assessment under the procedures in MCL 205.21. You have 60 days to respond before the assessment becomes final and collectible. Common adjustments include a missing City Schedule W (Treasury removes the withholding credit until you provide one) and a Schedule TC mismatch with the other city’s records.

If you owe a balance and cannot pay, request an installment agreement using the Michigan Treasury Collection Services Bureau before the April 15 deadline. Penalty continues to accrue at 5% per month up to 25% on unpaid tax under MCL 141.664, but interest can be reduced by getting on a plan early. A common misconception is that the IRS and Treasury share collection efforts — they do not, and ignoring a Detroit assessment will not be cured by paying the IRS.

Mistakes to Avoid When Filling Out the Form

• Filing Form 5118 when you were only a part-year resident. This overstates Detroit-source income and triggers an assessment within 90 days.
• Skipping Form 5121 City Schedule W. Treasury removes all withholding credit until the schedule arrives, turning a refund into a balance due.
• Using last year’s $600 exemption when the current year’s amount differs. A wrong exemption changes Line 14 and Line 16 dollar-for-dollar.
• Entering the nonresident 1.2% rate on Line 16. Underpays tax by half and produces a deficiency notice plus interest.
• Forgetting Schedule TC for tax paid to Highland Park, Hamtramck, or Grand Rapids. Loses the credit entirely; you cannot claim it later without an amended return.
• Listing W-2 box 18 instead of box 19 on City Schedule W. Box 18 is local wages, not local withholding — Treasury denies the credit.
• Mismatched federal AGI on Line 10. A different number from the IRS file triggers an automatic recompute and notice.
• Signing only one spouse on a joint return. Voids the MFJ election and forces Treasury to treat each spouse as MFS.
• Missing the April 15 deadline by even one day. Penalty starts at 5% of unpaid tax immediately.
• Sending a check without “2025 Form 5118” and your SSN in the memo. Payment cannot be matched, and balance-due interest keeps running.
• Claiming Social Security on Line 12 as a subtraction. Already excluded at the federal level — double-dipping triggers an assessment.
• Forgetting to check the residency box. Treasury kicks the return into manual review for up to 12 weeks.

Do’s and Don’ts

• Do pull the current-year form from the Treasury City Tax Forms page, because the revision date and exemption amount change every year.
• Do attach Form 5121 City Schedule W to every Form 5118 with W-2 withholding, because the credit is denied without it.
• Do keep a PDF copy of the e-file acknowledgment for at least 6 years, because Treasury can audit back that far on city returns.
• Do verify your bank routing number from a check, not a deposit slip, to prevent a bounced direct deposit.
• Do make estimated payments on Form 5123 if you expect to owe more than $100 at year end, to avoid the underpayment penalty.
• Do double-check that box 20 on each W-2 reads DETROIT, because that is what triggers the Schedule W credit on Treasury’s side.
• Don’t mix up resident Form 5118 with nonresident Form 5119 or part-year Form 5120 — using the wrong form delays processing by months.
• Don’t mail a paper return without USPS Certified Mail tracking, because lost-mail disputes go nowhere without proof.
• Don’t ignore a Letter of Inquiry — the 60-day clock runs whether you respond or not, and an assessment becomes final automatically.
• Don’t rely on tax software to “auto-detect” Detroit residency — manually confirm the city box, because suburban ZIPs can mis-flag.
• Don’t subtract Michigan state tax on Line 12 — only city-to-city credits qualify, and only on Schedule TC.
• Don’t sign in pencil or stamp a signature on a paper return — Treasury rejects both as unsigned.

Pros and Cons of Filing on Your Own vs. With Help

• Pro of filing on your own: Free or low-cost through MTO and budget software, which keeps more refund in your pocket.
• Pro of filing on your own: Faster turnaround because you control the timing and do not wait for an appointment.
• Pro of filing on your own: You learn the form, which makes amendments and future years much easier.
• Pro of filing on your own: You avoid the preparer-signature paid-preparer disclosure on page 2 of the form.
• Pro of filing on your own: Direct control over direct-deposit and refund-application choices.
• Con of filing on your own: Easy to miss the Schedule TC credit if you worked in another taxing city.
• Con of filing on your own: Self-employed filers often miscompute Line 11 additions or miss Renaissance Zone deductions.
• Con of filing on your own: No professional shield if Treasury issues an assessment — you handle the response yourself.
• Con of filing on your own: Higher error rate on City Schedule W when multiple W-2s show partial Detroit withholding.
• Con of filing on your own: Software still charges $25–$55 for the Detroit add-on at the major vendors, narrowing the savings.

City Schedule W vs. Schedule TC at a Glance

Schedule	Purpose
Form 5121 City Schedule W	Reconciles Detroit withholding from W-2 box 19 to Line 19 of Form 5118; required whenever any Detroit tax is withheld.
Schedule TC	Computes the credit for Michigan city tax paid to a different city on the same income; required whenever Line 17 is greater than zero.

FAQs

Do I file Form 5118 if I lived in Detroit only part of the year?

No. Part-year residents file Form 5120, not Form 5118. Filing 5118 as a part-year resident overstates city-source income and triggers an assessment.

Do I have to file Form 5118 if my employer already withheld Detroit tax?

Yes. Withholding is treated as a deposit, not a final payment. You must file to reconcile, claim a refund of any overpayment, or pay any shortfall.

Is the Detroit resident tax rate still 2.4%?

Yes. The resident rate is 2.4% under the City Income Tax Act and Detroit ordinance, and it has not changed since 2003.

Do I write my address on Line 1 if I have a P.O. box?

No. Form 5118 requires a Detroit street address to prove domicile. Use your physical residence on December 31 and add the P.O. box only as a mailing line.

Should I check Box (b) MFJ if my spouse lives outside Detroit?

No. Only the Detroit-resident spouse files Form 5118, and they should file Married Filing Separately. The nonresident spouse files Form 5119.

Do I include my W-2 box 18 number on City Schedule W?

No. Box 18 is local wages, not withholding. Use box 19 (the Detroit tax withheld) on the Schedule W reconciliation line.

Is Schedule TC required if I work in Detroit only?

No. Schedule TC only applies when you paid income tax to a different Michigan taxing city. A Detroit-only worker has no Schedule TC.

Do I list Social Security benefits on Line 12 as a subtraction?

No. Social Security is already excluded from federal AGI on Line 10, so subtracting again double-dips and triggers an assessment.

Is the filing deadline the same as the federal April 15?

Yes. Form 5118 is due April 15, the same day as federal Form 1040. Weekend or holiday shifts follow the federal calendar.

Do I need to file an extension separately for Detroit?

Yes. A federal extension does not extend Detroit. File Form 5209 to request a city extension, and pay any expected balance by April 15 to avoid penalty.

Should I sign in pencil to make corrections easier?

No. Pencil signatures are rejected. Sign in blue or black ink on paper, or use a self-select PIN for e-file.

Can I claim a Detroit version of the federal Earned Income Credit?

No. Detroit does not offer a city-level EITC. The credit only exists at the federal and Michigan state levels.

Do I attach a copy of my federal 1040 to Form 5118?

Yes. Treasury requires a copy of your federal 1040 with paper-filed Form 5118 to verify Line 10 federal AGI. E-filers transmit it electronically.

Is the $600 per-exemption amount the same every year?

No. Detroit publishes the exemption amount in each year’s instructions. Always confirm the current figure on the Form 5118 instructions before filing.