Michigan Quarterly Estimated Income Tax — Individuals

Scope. This skill covers Michigan Form MI-1040ES (quarterly estimated income tax vouchers) and Form MI-2210 (underpayment penalty) for full-year Michigan resident individuals who are sole proprietors, single-member LLCs, or W-2 earners with insufficient withholding. It covers the safe-harbor tests under MCL 206.301, the four quarterly installment due dates, the annualized income method for taxpayers with uneven income, and coordination with federal Form 1040-ES.

Out of scope. Estate and trust estimated payments (MI-1041ES), S-corp pass-through entity tax (PTET) estimated payments under MCL 206.813 (handled in a separate skill), corporate income tax estimates (Form 4913), multistate apportionment edge cases, and city-level estimated payments (Detroit D-1040ES and similar are filed separately with the city).

Quality tier. Q3 — AI-drafted, not independently verified. All rates, thresholds, and interest rates were researched on 2026-05-28 from official Michigan Department of Treasury publications and Revenue Administrative Bulletins. A qualified Michigan professional must review before any payment schedule is acted upon.

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Section 1: Metadata

Field	Value
Jurisdiction	Michigan (US-MI)
Tax type	Individual income tax — estimated payments
Primary form	Form MI-1040ES (quarterly voucher)
Penalty form	Form MI-2210 (Underpayment of Estimated Income Tax)
Tax year	2026 (vouchers paid April 2026 – January 2027)
Authority	Michigan Department of Treasury
Statute	MCL 206.301 (estimated tax); MCL 205.23 (interest); MCL 205.24 (penalty)
Version	0.1
Last updated	2026-05-28
Validation	AI-drafted — Q3 (pending Michigan CPA/EA verification)

Sources consulted

#	Source	URL
1	MCL 206.301 — Estimated Tax Installments	https://www.legislature.mi.gov/Laws/MCL?objectName=mcl-206-301
2	MCL 205.23 — Interest on underpayments	https://www.legislature.mi.gov/Laws/MCL?objectName=mcl-205-23
3	2026 MI-1040ES Vouchers & Instructions	https://www.michigan.gov/taxes/-/media/Project/Websites/taxes/Forms/IIT/TY2025/MI-1040ES-(2026).pdf
4	2025 MI-2210 Underpayment of Estimated Tax	https://www.michigan.gov/taxes/-/media/Project/Websites/taxes/Forms/IIT/TY2025/MI-2210.pdf
5	Revenue Administrative Bulletin 2026-1 (H1 2026 interest rate)	https://www.michigan.gov/taxes/rep-legal/rab/2026-revenue-administrative-bulletins/revenue-administrative-bulletin-2026-1
6	Revenue Administrative Bulletin 2026-5 (H2 2026 interest rate)	https://www.michigan.gov/taxes/rep-legal/rab/2026-revenue-administrative-bulletins/revenue-administrative-bulletin-2026-5
7	Michigan Treasury — Am I Required to Make Estimates?	https://www.michigan.gov/taxes/questions/iit/accordion/estimate/am-i-required-to-make-estimated-tax-payments-1
8	Michigan Treasury — Interest Rate Due on Under/Overpayments	https://www.michigan.gov/taxes/interest-rate
9	Michigan Treasury Online (MTO) portal	https://mto.treasury.michigan.gov/

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Section 2: Quick reference

Item	Value	Source
Estimated tax threshold	Expected tax > $500 after withholding and credits	MCL 206.301(1)
Safe harbor — current year	90% of current-year tax	MI-1040ES Instr.
Safe harbor — prior year (standard)	100% of prior-year tax (12-month return)	MI-1040ES Instr.
Safe harbor — high-income (AGI > $150k)	110% of prior-year tax	MI-1040ES Instr. [VERIFY:] see §5
Safe harbor — farmers/fishermen	66⅔% of current-year tax	MCL 206.301(4)
Q1 due date (TY 2026)	April 15, 2026	MCL 206.301(1)
Q2 due date	June 15, 2026	MCL 206.301(1)
Q3 due date	September 15, 2026	MCL 206.301(1)
Q4 due date	January 15, 2027	MCL 206.301(1)
Michigan flat tax rate (TY 2026)	4.25%	MCL 206.51
Interest rate — H1 2026	8.48% annual / 0.0002324 daily	RAB 2026-1
Interest rate — H2 2026	7.85% annual / 0.0002150 daily	RAB 2026-5
Late-payment penalty	10% of underpayment ($10 min/quarter)	MCL 205.24
Failure-to-file penalty	25% of tax due ($25 min/quarter)	MCL 205.24
Payment methods	MTO eCheck (free); debit card ($3.95); credit card (2.3%); mail + voucher	Treasury
Mail-in address	Michigan Department of Treasury, P.O. Box 30774, Lansing, MI 48909	MI-1040ES

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Section 3: Threshold determination — when MUST you make estimates

Under MCL 206.301(1), an individual must make quarterly estimated payments if the expected annual Michigan tax liability, after subtracting:

1. Michigan income tax withholding under MCL 206.351, AND
2. All allowable Michigan credits

exceeds $500.

Decision flow

Step 1: Compute expected Michigan AGI for TY 2026.
Step 2: Compute Michigan tax at 4.25% (after personal exemptions of $5,800/each).
Step 3: Subtract anticipated Michigan withholding (from W-2 Box 17, 1099 boxes, pension W-4P).
Step 4: Subtract anticipated credits (Homestead Property Tax Credit, Home Heating Credit, etc.).
Step 5: If remainder > $500 → MUST make estimates.
        If remainder ≤ $500 → no estimates required (but voluntary payments allowed).

Common triggers

Situation	Trigger?
Sole prop / SMLLC with no withholding	Almost always YES once net SE income > ~$13,000
W-2 earner with W-4 set correctly	Usually NO
W-2 earner with side gig (Schedule C)	Depends — compute step 5
Retiree with no MI withholding on 1099-R	Yes if subtraction does not zero out tax
Capital gains windfall in current year	Yes — may also need annualized method (§7)
Both spouses earn — MFJ	Compute on combined liability

[VERIFY:] MCL 206.301 uses the singular "person" — joint filers compute the threshold on the combined liability shown on the joint MI-1040. Confirm with 2026 MI-1040ES instructions.

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Section 4: Safe-harbor calculation

A taxpayer who meets any one of the following safe harbors avoids the underpayment penalty under MCL 205.24, regardless of the final balance due on the MI-1040:

Safe harbor 1 — Current-year 90%

Pay (through withholding + estimates) at least 90% of the actual TY 2026 Michigan tax liability.

Safe harbor 2 — Prior-year 100%

Pay at least 100% of the TY 2025 Michigan tax shown on the MI-1040, line 20 (total tax), provided:

• The TY 2025 return covered 12 full months, AND
• A TY 2025 MI-1040 was actually filed.

Safe harbor 3 — High-income prior-year 110%

If TY 2025 federal AGI exceeded $150,000 ($75,000 if MFS), the prior-year safe harbor is 110% of TY 2025 Michigan tax — not 100%.

[VERIFY:] Michigan's MI-1040ES 2026 instructions reference the federal §6654(d)(1)(C) higher-income test. The MI safe harbor is presented as "100% (or 110% if AGI > $150k)" by Michigan Treasury and by the official MI-1040ES instructions. Confirm that the AGI threshold language continues to apply at $150,000 for TY 2026 — the figure has not been indexed and mirrors the federal threshold under §6654(d)(1)(C).

Safe harbor 4 — Farmers, fishermen, seafarers (MCL 206.301(4))

If at least two-thirds of expected AGI is from farming, fishing, or seafaring, taxpayer may pay:

• 66⅔% of current-year tax in a single installment by January 15, OR
• File and pay full balance by March 1 of the following year.

Lower-of test

The taxpayer pays the lower of (a) the prior-year safe harbor and (b) 90% of current-year. Most software defaults to the prior-year amount because it is fixed and certain. Use current-year 90% only if current-year income has dropped materially.

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Section 5: Regular installment method — four equal payments

Under MCL 206.301(2), each installment equals one-quarter (¼) of the estimated annual tax (after expected withholding).

Formula

Required annual payment (RAP) = lower of:
   (a) 90% × TY 2026 expected Michigan tax
   (b) 100% (or 110% if high-income) × TY 2025 Michigan tax
   (c) — for farmers/fishermen — 66⅔% × TY 2026 expected tax

Quarterly installment = (RAP − expected TY 2026 withholding) ÷ 4

Timing table — TY 2026

Installment	Period covered	Due date	Cumulative % required
Q1	Jan 1 – Mar 31, 2026	April 15, 2026	25%
Q2	Apr 1 – May 31, 2026	June 15, 2026	50%
Q3	Jun 1 – Aug 31, 2026	September 15, 2026	75%
Q4	Sep 1 – Dec 31, 2026	January 15, 2027	100%

If a due date falls on a Saturday, Sunday, or Michigan legal holiday, the deadline shifts to the next business day (MCL 205.27a).

Withholding rule

Michigan, like federal, treats withholding as paid evenly across the four quarters unless the taxpayer elects to treat it as paid when actually withheld. This is favorable to taxpayers whose withholding is back-loaded (e.g., a December bonus with full MI withholding can cover earlier underpayments).

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Section 6: Annualized income method (uneven income)

For taxpayers whose income arrives unevenly across the year — typical patterns include consulting engagements that close in Q3, capital gains realized in Q4, or seasonal businesses — Michigan permits an annualized income installment method analogous to federal Form 2210 Schedule AI.

The method is implemented on Form MI-2210, Part 3 (Annualized Income Worksheet).

Annualization periods

Period	Months covered	Annualization factor
Period 1	Jan 1 – Mar 31	× 4
Period 2	Jan 1 – May 31	× 2.4
Period 3	Jan 1 – Aug 31	× 1.5
Period 4	Jan 1 – Dec 31	× 1

Mechanics

1. Compute Michigan AGI for each cumulative period (YTD through Mar 31, May 31, Aug 31, Dec 31).
2. Multiply by the annualization factor for that period to get annualized AGI.
3. Subtract pro-rated exemptions and apply 4.25%.
4. Multiply the annualized tax by the cumulative safe-harbor percentage (22.5%, 45%, 67.5%, 90% for the four periods — these are 90% × 25%/50%/ 75%/100%).
5. Subtract withholding allocated to that period and prior installments paid.
6. Result = required installment for that quarter.

Worked snippet

A consultant with TY 2026 income heavily weighted to Q3:

Period	YTD MI AGI	Annualized AGI	Annualized tax (4.25%)	Cum. required (× factor)	Prior installments	This installment
1 (Mar 31)	$8,000	$32,000	$1,360	$306 (22.5%)	0	$306
2 (May 31)	$15,000	$36,000	$1,530	$689 (45%)	$306	$383
3 (Aug 31)	$90,000	$135,000	$5,738	$3,873 (67.5%)	$689	$3,184
4 (Dec 31)	$140,000	$140,000	$5,950	$5,355 (90%)	$3,873	$1,482

Without annualization the consultant would owe $1,488 per quarter (roughly $5,950 ÷ 4). With annualization the Q1 and Q2 payments are tiny because little income had been earned. Total paid across all four quarters is identical, but no underpayment penalty accrues for Q1 and Q2.

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Section 7: Form MI-1040ES voucher — line by line

The 2026 MI-1040ES is a four-voucher set. Each voucher is identical except for the period and due date.

Voucher line	Field	What to enter
1	Taxpayer's SSN	Primary filer SSN
2	Spouse SSN (if joint)	Spouse SSN
3	Filer's name and address	Primary + spouse names; mailing address
4	Voucher number (1, 2, 3, 4)	Pre-printed; matches quarter
5	Amount of estimated tax payment	$ amount in whole dollars
6	Make check payable to	"State of Michigan" — write filer SSN and "2026 MI-1040ES" on memo line

Mail-in destination

Michigan Department of Treasury P.O. Box 30774 Lansing, MI 48909

Joint vs separate filers (MCL 206.311)

• Joint filers may file a single MI-1040ES voucher set covering both spouses, OR each spouse may file separately.
• If a joint MI-1040 will be filed, joint estimates are easiest — credits apply to the combined liability.
• If one spouse later files MFS, the estimates can be allocated by mutual agreement (default allocation per MCL 206.311(2) is by proportion of each spouse's separate tax to the combined tax).

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Section 8: Underpayment penalty — Form MI-2210

When required estimates are not paid (or are paid late or short), MI-2210 calculates:

1. Underpayment penalty — a fixed percentage charge, AND
2. Interest — at the quarterly Treasury rate.

Penalty component (MCL 205.24)

Failure	Rate	Minimum
Failure to pay enough estimate / paid late	10% of the underpayment	$10 per quarter
Failure to file an estimate at all	25% of the underpayment	$25 per quarter

Interest component (MCL 205.23(2))

Interest accrues on each quarterly underpayment from the due date of that installment to the earlier of (a) the date the underpayment was paid, or (b) April 15 of the following year (the MI-1040 filing deadline).

The annual rate is set twice a year by Treasury under MCL 205.23(2) at 1 percentage point above the adjusted prime rate charged by three large Michigan commercial banks.

Period	Annual rate	Daily rate	Authority
Jan 1 – Jun 30, 2026	8.48%	0.0002324	RAB 2026-1
Jul 1 – Dec 31, 2026	7.85%	0.0002150	RAB 2026-5

[VERIFY:] Rates for 2027 will be issued in RAB 2026-13 (December 2026) and RAB 2027-5 (June 2027). Check michigan.gov/taxes/interest-rate before finalizing any MI-2210.

MI-2210 form structure

Part	Function
Part 1	Required Annual Payment (lower of 90% current / 100% (or 110%) prior)
Part 2	Short Method (regular installments — equal quarterly amounts)
Part 3	Annualized Income Worksheet (for uneven income; see §6)
Part 4	Penalty and Interest Computation (per quarter)

Penalty waiver / reasonable cause

Under MCL 205.24(4) the Treasury may waive the underpayment penalty (but not interest) for:

• Casualty, disaster, or other unusual circumstance where imposition would be inequitable;
• Reasonable cause shown — e.g., reliance on incorrect written advice from Treasury, retirement after age 62, or first-year self-employment;
• Death of the taxpayer during the year.

Submit a written reasonable-cause statement with MI-2210. Interest is not waivable.

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Section 9: Payment methods

MTO (Michigan Treasury Online) — preferred

1. Navigate to https://mto.treasury.michigan.gov/.
2. Sign in (or create an Individual account using SSN + prior-year AGI).
3. Select "Make a Payment" → "Estimated Tax (MI-1040ES)".
4. Choose tax year 2026 and the installment quarter (1–4).
5. Enter bank routing + account number for ACH eCheck (no fee), OR enter debit/credit card details.
6. Confirm — keep the MTO confirmation number for the file.

Mail with voucher

Detach the appropriate quarterly voucher from MI-1040ES, attach check payable to "State of Michigan", write SSN and "2026 MI-1040ES Q[n]" on memo line, mail to P.O. Box 30774, Lansing, MI 48909. Use certified mail for evidence of timely filing.

Bank ACH debit (recurring)

Through MTO a taxpayer can schedule all four quarterly debits in advance on the four statutory due dates. This is the recommended method for sole-prop clients who want to "set and forget".

Card fees

• Debit card: $3.95 flat fee per transaction.
• Credit card: 2.3% of payment (paid to processor, not Treasury).

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Section 10: Coordination with federal Form 1040-ES

Michigan due dates match federal due dates exactly:

Quarter	Federal 1040-ES	Michigan MI-1040ES
Q1	April 15, 2026	April 15, 2026
Q2	June 15, 2026	June 15, 2026
Q3	September 15, 2026	September 15, 2026
Q4	January 15, 2027	January 15, 2027

Practical workflow

1. Compute federal Schedule C net profit + SE tax under the us-schedule-c-and-se-computation skill.
2. Run federal estimated tax via us-quarterly-estimated-tax skill (1040-ES).
3. Apply the federal AGI figure as the input to the Michigan threshold test (§3) and the MI 4.25% computation (Michigan AGI starts from federal AGI — see mi-income-tax skill).
4. Compute MI required annual payment and divide by 4.
5. Schedule both federal and Michigan payments on MTO + EFTPS in the same session each quarter.

Differences to watch

Federal	Michigan
25/25/25/25 installments	25/25/25/25 installments (identical)
§6654 safe harbor 100%/110%	MCL 206.301 safe harbor 100%/110% (parallel)
§6654 interest rate (federal short-term + 3)	MCL 205.23 (prime + 1, set semi-annually)
Form 2210	Form MI-2210
EFTPS / IRS Direct Pay	Michigan Treasury Online (MTO)
Form 1040-ES voucher	Form MI-1040ES voucher

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Section 11: Tier 1 deterministic rules + Tier 2 judgment rules

Tier 1 — deterministic (do not require judgment)

ID	Rule
T1-01	Threshold = $500 expected liability after withholding and credits (MCL 206.301(1))
T1-02	Four installments due April 15, June 15, September 15, January 15
T1-03	Each installment = ¼ of required annual payment (RAP) less expected withholding ÷ 4
T1-04	RAP = lower of (a) 90% current year or (b) 100% (110% if AGI > $150k) prior year
T1-05	Farmer/fisherman alternative = 66⅔% by Jan 15 OR full payment by Mar 1 (MCL 206.301(4))
T1-06	Late/under penalty = 10% of shortfall, $10 min per quarter
T1-07	Failure to file estimate = 25% penalty, $25 min per quarter
T1-08	Interest rate = Treasury-set semi-annual rate under MCL 205.23
T1-09	Joint filers may file one voucher set (MCL 206.311)
T1-10	Make check payable to "State of Michigan" with SSN + "2026 MI-1040ES Q[n]" on memo

Tier 2 — judgment-required (flag for reviewer)

ID	Situation	Judgment call
T2-01	High-income 110% trigger	Use TY 2025 federal AGI; if > $150k, default to 110%
T2-02	Uneven income — use annualized method?	Use if Q1/Q2 income < 25% of annual; document
T2-03	First-year self-employed (no prior-year liability)	Only current-year 90% safe harbor available; consider reasonable-cause waiver
T2-04	Mid-year change in withholding	Recompute Q3/Q4; do not amend Q1/Q2
T2-05	Capital gains windfall Q4	Annualized method usually beats regular installment
T2-06	Spouse files MFS after joint estimates paid	Allocate per MCL 206.311(2) proportional rule
T2-07	Detroit / Grand Rapids resident with city tax	City has separate estimated tax — do not combine
T2-08	Reasonable-cause waiver request	Draft written statement; cite specific MCL 205.24(4) ground

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Section 12: Worked examples

Example 1 — Steady-income sole proprietor ($120k expected)

Facts. Single filer; full-year Michigan resident; sole proprietor with expected TY 2026 Schedule C net profit of $120,000; no W-2 withholding; TY 2025 MI-1040 total tax was $4,750 (federal AGI $115k); no city income tax.

Step 1 — Determine if estimates required.

• Expected MI AGI ≈ $120,000 − ½ SE tax adjustment ($8,478) = $111,522.
• Less personal exemption $5,800 → MI taxable $105,722.
• MI tax @ 4.25% = $4,493.
• No withholding, no credits → expected liability $4,493 > $500. Estimates required.

Step 2 — Required annual payment (RAP).

• Current-year 90%: $4,493 × 90% = $4,044.
• Prior-year 100%: $4,750. (Federal AGI was $115k, under $150k, so 100% applies.)
• RAP = lower = $4,044.

Step 3 — Quarterly installment.

• $4,044 ÷ 4 = $1,011 per quarter.

Step 4 — Voucher schedule.

Quarter	Due date	Amount
Q1	April 15, 2026	$1,011
Q2	June 15, 2026	$1,011
Q3	September 15, 2026	$1,011
Q4	January 15, 2027	$1,011
Total		$4,044

Schedule four ACH debits via MTO at sign-up; no further action required.

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Example 2 — Sole prop with Q3 income spike (annualized method)

Facts. Single filer; consultant; total 2026 net profit $140,000 but landed in this distribution: $8,000 by Mar 31; $15,000 by May 31; $90,000 by Aug 31; $140,000 by Dec 31. TY 2025 prior tax was $3,200.

Regular installment method would require $140,000 × ~4% MI = ~$5,950 annual tax × 90% ÷ 4 = $1,339/quarter — but the taxpayer earned only $8,000 by Mar 31, so $1,339 due April 15 is roughly 67% of all income earned to that date. Painful.

Annualized method (MI-2210 Part 3):

Period	YTD MI AGI	× Factor	Annualized	× 4.25%	Cum. 22.5/45/67.5/90%	Less prior pmts	This pmt
1 (3/31)	$8,000	4.00	$32,000	$1,360	$306	0	$306
2 (5/31)	$15,000	2.40	$36,000	$1,530	$689	$306	$383
3 (8/31)	$90,000	1.50	$135,000	$5,738	$3,873	$689	$3,184
4 (12/31)	$140,000	1.00	$140,000	$5,950	$5,355	$3,873	$1,482
Total							$5,355

The annualized method front-loads cash to Q3 when the income actually arrived. No MI-2210 penalty accrues because each cumulative payment meets the cumulative safe-harbor percentage.

[VERIFY:] Annualization factors mirror federal Schedule AI; confirm the MI-2210 (2026 revision) replicates the federal 4 / 2.4 / 1.5 / 1 sequence.

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Example 3 — High-income W-2 earner with withholding shortfall

Facts. MFJ; both spouses W-2; combined wages $300,000; combined federal AGI 2025 was $285,000 (i.e., > $150k threshold); MI withholding for 2026 projected at $9,500 against expected MI tax of $12,400; TY 2025 MI total tax was $11,800. No self-employment income.

Step 1 — Estimates required?

• Expected MI tax $12,400 − withholding $9,500 = $2,900 shortfall.
• $2,900 > $500 → Estimates required.

Step 2 — RAP under high-income rule.

• Current-year 90%: $12,400 × 90% = $11,160.
• Prior-year 110% (because 2025 AGI > $150,000): $11,800 × 110% = $12,980.
• RAP = lower = $11,160.

Step 3 — Subtract withholding spread evenly.

• Required payments net of withholding: $11,160 − $9,500 = $1,660.
• Quarterly installment: $1,660 ÷ 4 = $415 per quarter.

Step 4 — Voucher schedule.

Quarter	Due date	Amount
Q1	April 15, 2026	$415
Q2	June 15, 2026	$415
Q3	September 15, 2026	$415
Q4	January 15, 2027	$415
Total estimates		$1,660
+ Withholding		$9,500
= RAP		$11,160

Step 5 — Alternative: increase W-4 withholding.

For W-2 couples, increasing Michigan withholding via MI-W4 line 6 ("additional amount per pay") is usually administratively easier than quarterly vouchers — and withholding is treated as paid evenly across all four quarters even if added in November, which can fully cure an underpayment for Q1–Q3.

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Section 13: Refusal catalogue

ID	Situation	Action
MI-EST-R-01	Estate or trust estimated payments (MI-1041ES)	Refuse — separate fiduciary skill required
MI-EST-R-02	S-corp / partnership PTET estimated payments (MCL 206.813)	Refuse — load mi-ptet-estimated-tax (separate skill, pending)
MI-EST-R-03	Corporate Income Tax estimates (Form 4913)	Refuse — load mi-corporate-income-tax
MI-EST-R-04	Multistate apportionment with Michigan as one of several states	Refuse — flag for professional review
MI-EST-R-05	Part-year or non-resident estimates (Schedule NR)	Refuse — out of scope
MI-EST-R-06	Detroit / Grand Rapids / other city estimates (D-1040ES, etc.)	Refuse — separate city return
MI-EST-R-07	Tax year other than current (TY 2024 or earlier)	Refuse — rates and rules may differ
MI-EST-R-08	Michigan Business Tax (MBT) carryover entities	Refuse — different tax regime
MI-EST-R-09	Composite return estimated payments for non-resident members	Refuse — separate skill required

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Section 14: Form mapping

Michigan form	Purpose	Federal counterpart
MI-1040ES (voucher 1–4)	Quarterly estimated payment	Form 1040-ES (voucher 1–4)
MI-1040ES instructions + worksheet	Computation worksheet	Form 1040-ES worksheet
MI-2210 Part 1	Required Annual Payment	Form 2210 Part I
MI-2210 Part 2	Short method (equal installments)	Form 2210 Part III, Short Method
MI-2210 Part 3	Annualized Income Worksheet	Form 2210 Schedule AI
MI-2210 Part 4	Penalty and Interest computation	Form 2210 Part III, Regular Method
MI-W4	Employee withholding certificate	Form W-4
MI-1040 line 28	Estimated payments applied	Form 1040 line 26
MI-1040 line 36	Refund overpayment applied to next year	Form 1040 line 36

MI-1040ES voucher line numbers (2026)

Line	Field
1	Filer SSN
2	Spouse SSN (if joint)
3	Filer name and address
4	Voucher number (1, 2, 3, or 4)
5	Amount of estimated payment
6	Check payable to "State of Michigan"; write SSN + "2026 MI-1040ES Q[n]"

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Section 15: Provenance

Element	Source	Confidence
$500 threshold	MCL 206.301(1)	High
Due dates Apr 15 / Jun 15 / Sep 15 / Jan 15	MCL 206.301(1)	High
90% / 100% / 110% safe harbor	MI-1040ES 2026 instructions	High ([VERIFY:] 110% AGI threshold)
Farmer/fisherman 66⅔%	MCL 206.301(4)	High
4.25% flat rate	MCL 206.51	High
Personal exemption $5,800	MCL 206.30; 2026 RAB	High
10% / 25% penalty	MCL 205.24	High
Interest rate 8.48% (H1 2026)	RAB 2026-1	High
Interest rate 7.85% (H2 2026)	RAB 2026-5	High
Annualization factors 4 / 2.4 / 1.5 / 1	MI-2210 Part 3 (2025 form)	Medium — [VERIFY:] 2026 form
Joint filer single voucher allowance	MCL 206.311	High
Reasonable cause waiver grounds	MCL 205.24(4)	High
MTO payment portal mechanics	mto.treasury.michigan.gov walkthrough	Medium
Card / debit fees ($3.95 / 2.3%)	MTO payment processor disclosures	Medium — rates may change

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Disclaimer

This skill and its outputs are provided for informational and computational purposes only and do not constitute tax, legal, or financial advice. Open Accountants and its contributors accept no liability for any errors, omissions, or outcomes arising from the use of this skill. All outputs must be reviewed and signed off by a qualified professional before filing or acting upon.

The most up-to-date, verified version of this skill is maintained at openaccountants.com.

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