North Dakota Individual Quarterly Estimated Income Tax Skill

Scope. This skill covers North Dakota individual quarterly estimated income tax payments (Form ND-1ES) and the underpayment-of-estimated-tax interest computation (Schedule ND-1UT) for full-year ND residents who are sole proprietors, single-member LLC owners, S-corp shareholders, or W-2 employees with insufficient withholding. Tax year 2025 (payments due April 15, 2025 through January 15, 2026; reconciled on the Form ND-1 filed by April 15, 2026).

Quality tier. Q3 — AI-drafted, not independently verified. All outputs must be reviewed by a qualified tax professional before filing or payment.

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Section 1: Metadata

Field	Value
Tax type	Individual income tax — quarterly estimated payments
Jurisdiction	North Dakota (US-ND)
Tax year	2025 (TY 2025 quarterly payments and TY 2026 Q1)
Primary form	Form ND-1ES (Estimated Income Tax — Individuals)
Reconciliation form	Form ND-1 (Individual Income Tax Return)
Underpayment form	Schedule ND-1UT (Underpayment of Estimated Individual Income Tax)
Federal counterpart	Form 1040-ES
Tax authority	North Dakota Office of State Tax Commissioner
Payment portal	North Dakota Taxpayer Access Point (ND TAP)
Statute	N.D.C.C. §57-38-62
Regulation	N.D. Admin Code 81-03-04-01 through 81-03-04-02
Underpayment interest rate	12% per annum [VERIFY: confirm against current Tax Commissioner publication for TY 2025]
Threshold	Net tax liability expected to exceed $1,000 [VERIFY]

Sources:

• N.D.C.C. §57-38-62 (estimated tax statute): https://ndlegis.gov/cencode/t57c38.html
• N.D. Admin Code 81-03-04-02: https://www.law.cornell.edu/regulations/north-dakota/N-D-A-C-81-03-04-02
• Form ND-1ES (TY 2025): https://www.tax.nd.gov/sites/www/files/documents/forms/individual/2024-iit/28709-form-nd-1es-2025.pdf
• Schedule ND-1UT (TY 2025): https://www.tax.nd.gov/sites/www/files/documents/forms/individual/2025-iit/28704-schedule-nd-1ut-2025.pdf
• 2025 Individual Income Tax Booklet: https://www.tax.nd.gov/sites/www/files/documents/forms/individual/2025-iit/2025-individual-income-tax-booklet.pdf

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Section 2: Quick reference

Threshold

Item	Value
ND net tax liability threshold	More than $1,000 [VERIFY]
Federal trigger (required by §57-38-62)	Taxpayer must also be required to pay federal estimated tax

Safe harbor (lower of)

Test	Amount
(a) Current-year test	90% of TY 2025 ND net tax liability
(b) Prior-year test	100% of TY 2024 ND net tax liability
(c) Qualified farmer / fisherman	66⅔% of current-year liability

Note on the 110% high-income variant. Unlike federal Form 2210 — which requires 110% of the prior year for taxpayers with prior-year AGI over $150,000 — North Dakota's statute and Schedule ND-1UT use a flat 100% prior-year test with no high-income step-up. [VERIFY against the 2025 Schedule ND-1UT instructions before relying on this for high-AGI clients.]

Four installment due dates (TY 2025 calendar-year filer)

Installment	Due date	Percentage of annual required payment
Q1	April 15, 2025	25%
Q2	June 15, 2025	25%
Q3	September 15, 2025	25%
Q4	January 15, 2026	25%

Same calendar as federal Form 1040-ES.

Underpayment interest rate

Period	Rate
TY 2025	12% per annum, simple interest, computed from each installment due date to the earlier of the date paid or the original Form ND-1 due date (April 15, 2026) [VERIFY: confirm rate in 2025 Schedule ND-1UT instructions]

Payment methods

Method	Notes
ND Taxpayer Access Point (TAP)	https://apps.nd.gov/tax/tap — ACH debit, credit card
Paper check + Form ND-1ES voucher	Make check payable to "ND State Tax Commissioner"
Direct debit via TAP scheduled payments	Schedule all four installments in advance
Credit / debit card via TAP	Third-party convenience fees apply

No electronic-payment mandate currently published for individual estimated tax at any threshold. [VERIFY]

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Section 3: Threshold determination — when must you make estimated payments

Per N.D.C.C. §57-38-62 and the Form ND-1ES instructions, a North Dakota individual taxpayer must make estimated payments if both of the following are true for the tax year:

1. The taxpayer is required to pay federal estimated income tax (i.e., the federal safe-harbor rules of IRC §6654 would otherwise impose a federal underpayment penalty); and
2. The taxpayer's expected ND net tax liability for the year exceeds $1,000 [VERIFY].

ND net tax liability = ND income tax (Form ND-1, Line 22 area) less allowable credits and less ND income tax withheld (W-2 Box 17 and 1099 ND-source withholding).

Practical decision tree

• If withholding + credits ≥ 100% of prior-year ND tax → no estimates required (safe-harbor met by withholding alone).
• If expected ND liability ≤ $1,000 after withholding → no estimates required (de minimis).
• If neither of the above → estimates required; compute safe harbor in Section 4.

Statutory de minimis exception (N.D. Admin Code 81-03-04-02(3)(d))

Interest is waived where current-year tax liability exceeds withholding by less than $500, even if estimates were technically required. This is a penalty-relief rule, not a filing exemption — the taxpayer should still make estimated payments where prudent.

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Section 4: Safe-harbor calculation

The taxpayer's required annual payment is the lesser of:

• (a) Current-year safe harbor: 90% of the ND net tax liability shown on the current-year Form ND-1; or
• (b) Prior-year safe harbor: 100% of the ND net tax liability shown on the prior-year Form ND-1.

The prior-year test is unavailable if:

• The prior-year return was not filed; or
• The prior-year return covered fewer than 12 months; or
• The taxpayer had no ND tax liability in the prior year (in which case current year is the only test).

Worked safe-harbor calc

A taxpayer's TY 2024 ND tax was $4,000. They expect TY 2025 ND tax of $6,800.

• 90% × $6,800 = $6,120 (current-year)
• 100% × $4,000 = $4,000 (prior-year) ← lesser

Required annual payment = $4,000.

If TY 2025 withholding will be $1,200, the four installments must collectively total at least $4,000 − $1,200 = $2,800, i.e., $700 per quarter under the regular installment method.

Joint vs. separate prior year

If the taxpayer was MFS in the prior year and is MFJ in the current year, the prior-year tests for both spouses are summed to determine the joint prior-year safe harbor (N.D. Admin Code 81-03-04-02).

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Section 5: Regular installment method — the four equal payments

Once the required annual payment is fixed, the regular installment method allocates 25% to each quarter:

Q	Cumulative required by due date	Marginal Q payment
Q1	25% × annual	25%
Q2	50% × annual	25%
Q3	75% × annual	25%
Q4	100% × annual	25%

ND withholding is deemed paid evenly across the four quarters unless the taxpayer elects to treat it as paid when actually withheld (rare and disadvantageous).

The taxpayer satisfies each quarterly threshold by the sum of (a) ¼ of expected withholding plus (b) the ND-1ES voucher payment for that quarter.

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Section 6: Annualized income installment method

Where income is lumpy or back-loaded (e.g., a freelancer who closes a major contract in Q3, or an S-corp shareholder receiving a December distribution), the regular ¼-each-quarter method overstates Q1/Q2 requirements. The annualized income installment method lets the taxpayer match installment size to actual cumulative income.

ND follows the federal Schedule AI approach by reference: if the taxpayer utilizes the annualized income installment method for federal purposes, the ND underpayment interest is waived to the corresponding extent (N.D. Admin Code 81-03-04-02(3)(c)).

Annualization factors (calendar-year)

Installment	Period ending	Months	Annualization factor	Installment %
Q1	March 31	3	× 4	22.5% (90% / 4)
Q2	May 31	5	× 2.4	45% cumulative
Q3	August 31	8	× 1.5	67.5% cumulative
Q4	December 31	12	× 1	90% cumulative

The taxpayer must complete the annualized worksheet (federal Schedule AI is the template; ND does not publish a standalone state annualization schedule — the federal schedule is attached or reproduced in support of Schedule ND-1UT columns).

Worked example — Q3 income spike

A freelance software developer in Fargo expects $140,000 of ND-taxable income for TY 2025, but the income arrives as follows:

Period through	Cumulative ND taxable income	Annualized	Tax at ND rates (single)
Mar 31	$12,000	$48,000	$0 (within 0% bracket)
May 31	$24,000	$57,600	$178
Aug 31	$60,000	$90,000	$810
Dec 31	$140,000	$140,000	$1,786

Annualized required installment amounts (90% × annualized tax × installment percent):

Q	Cumulative required (rounded)	Marginal Q payment
Q1	22.5% × $0 = $0	$0
Q2	45% × $178 = $80	$80
Q3	67.5% × $810 = $547	$467
Q4	90% × $1,786 = $1,607	$1,060

Versus the regular method (¼ × $1,607 = ~$402 per quarter), the annualized method shifts ~$800 of payment from Q1/Q2 into Q3/Q4 while still avoiding underpayment interest.

Attach a reproduction of the federal annualization worksheet to Schedule ND-1UT when filing Form ND-1.

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Section 7: Form ND-1ES voucher mechanics

Form ND-1ES is a single-page voucher (one per installment). The taxpayer prepares one voucher per quarter when paying by check.

Voucher fields

Field	Source
Tax year	"2025" (or the year the installment relates to)
Installment number	1, 2, 3, or 4
Name, SSN, spouse SSN if joint	From last filed Form ND-1
Mailing address	Current address
Amount paid	The quarterly installment

Mailing address

Office of State Tax Commissioner PO Box 5622 Bismarck, ND 58506-5622

[VERIFY: confirm address from current 2025 ND-1ES voucher]

TAP electronic payment

For TAP payments, no paper voucher is required — the electronic posting through TAP serves as the voucher. The taxpayer logs into https://apps.nd.gov/tax/tap and selects "Make a Payment" → "Individual Income Tax" → "Estimated Payment."

Recordkeeping

The taxpayer should retain confirmation numbers (TAP) or cancelled checks for each installment to support Form ND-1 Line 27 (Estimated payments) when filing the annual return.

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Section 8: Underpayment interest — Schedule ND-1UT

If any installment is underpaid (paid late or paid in a smaller amount than the required installment), the taxpayer owes underpayment interest computed on Schedule ND-1UT (SFN 28704). The Schedule attaches to Form ND-1.

Computation outline (simplified)

For each of the four installments:

1. Compute the required installment (¼ of the required annual payment, OR the annualized installment if Schedule AI is used).
2. Compute payments applied to that installment: ¼ of withholding + ND-1ES payments made by or before the installment due date.
3. Underpayment = (1) − (2), if positive.
4. Days outstanding = from installment due date to the earlier of (a) the date the underpayment is paid (via a later ND-1ES voucher or April-15 balance due) or (b) April 15, 2026.
5. Interest = Underpayment × 12% × (Days / 365).

The sum of the four interest computations flows to Form ND-1 as additional amount due.

Statutory waivers (N.D. Admin Code 81-03-04-02(3))

Interest may be waived in any of the following cases:

Subsection	Waiver
(3)(a)	Qualified farmer who files federal return by March 1 and pays federal in full by that date
(3)(b)	Qualified farmer making one combined federal+state installment by January 15
(3)(c)	Taxpayer using the federal annualized income installment method (state interest waived in proportion)
(3)(d)	De minimis — current-year liability exceeds withholding by less than $500

Reasonable-cause waiver

The Tax Commissioner may waive interest under general reasonable-cause authority (illness, casualty, disaster, or other circumstance preventing timely payment). The taxpayer requests waiver in a signed statement attached to Form ND-1. [VERIFY: confirm administrative process in the current ND-1 booklet.]

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Section 9: Payment methods

ND Taxpayer Access Point (TAP)

• URL: https://apps.nd.gov/tax/tap
• Login required (one-time enrollment for new users)
• Payment types: ACH debit (free), credit/debit card (third-party convenience fee, ~2.5%)
• Confirmation: emailed receipt with confirmation number
• Scheduling: all four installments can be scheduled in advance from a single TAP session — recommended for steady-income clients

Paper check + Form ND-1ES voucher

• Make payable to "ND State Tax Commissioner"
• Write SSN and "2025 ND-1ES" on the memo line
• Mail with the printed voucher to the Bismarck PO Box [VERIFY current address]
• USPS postmark date controls timeliness

Direct debit via TAP scheduled payments

• Same as TAP but the taxpayer sets the debit dates in advance for all four quarters
• Useful for clients who want set-and-forget compliance

No electronic mandate

ND does not currently impose an electronic-payment mandate on individual estimated tax at any threshold [VERIFY against current Tax Commissioner guidance], though TAP is strongly recommended.

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Section 10: Coordination with federal Form 1040-ES

The ND quarterly calendar aligns exactly with the federal Form 1040-ES calendar:

Installment	Federal 1040-ES	ND-1ES
Q1	April 15, 2025	April 15, 2025
Q2	June 15, 2025	June 15, 2025
Q3	September 15, 2025	September 15, 2025
Q4	January 15, 2026	January 15, 2026

Practical workflow

1. Compute the federal required annual payment on Form 1040-ES worksheet (90% current / 100% or 110% prior depending on prior-year AGI).
2. Compute the ND required annual payment using the state safe-harbor tests (90% / flat 100% — no 110% step-up).
3. Schedule both federal (IRS Direct Pay or EFTPS) and state (ND TAP) payments for the same four dates.
4. If the federal taxpayer uses the annualized income installment method on federal Schedule AI, propagate the annualization to Schedule ND-1UT to preserve the state interest waiver under N.D. Admin Code 81-03-04-02(3)(c).

Independence of safe harbors

The federal and ND safe harbors are independent — meeting the federal safe harbor does not satisfy the ND safe harbor. A taxpayer who is paid up federally via withholding alone may still owe ND estimates if their ND-1 line 27 prior- year amount is low (e.g., due to W-2 withholding being primarily federal with little ND-source withholding).

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Section 11: Tier 1 rules — deterministic

Rule ID	Rule	Source
NDES-T1-01	Estimated tax required if expected ND net tax liability > $1,000 AND federal estimated tax is also required	N.D.C.C. §57-38-62; Form ND-1ES instructions
NDES-T1-02	Safe harbor = lesser of (a) 90% current year OR (b) 100% prior year	N.D. Admin Code 81-03-04-02
NDES-T1-03	No 110% high-income variant — flat 100% prior-year test [VERIFY]	N.D. Admin Code 81-03-04-02
NDES-T1-04	Four equal installments due April 15, June 15, September 15, January 15	Form ND-1ES
NDES-T1-05	Underpayment interest rate = 12% per annum simple [VERIFY for TY 2025]	Schedule ND-1UT instructions
NDES-T1-06	Withholding deemed paid evenly unless taxpayer elects otherwise	Schedule ND-1UT
NDES-T1-07	De minimis waiver if current-year tax exceeds withholding by < $500	N.D. Admin Code 81-03-04-02(3)(d)
NDES-T1-08	Qualified farmer (>⅔ gross from farming) — single Jan 15 installment OR March 1 file + pay	N.D. Admin Code 81-03-04-02(3)(a),(b)
NDES-T1-09	Annualized installment method per federal Schedule AI waives state interest in proportion	N.D. Admin Code 81-03-04-02(3)(c)
NDES-T1-10	Prior-year safe harbor unavailable if prior return not filed or < 12 months	N.D. Admin Code 81-03-04-02

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Section 12: Tier 2 rules — requires judgment

Rule ID	Situation	Guidance
NDES-T2-01	Q3 / Q4 income spike (S-corp distribution, contract close)	Consider annualized installment method; preserve federal Schedule AI for state interest waiver
NDES-T2-02	Mid-year ND move-in	Part-year residents fall outside this skill (see Refusal R-NDES-04); coordinate with Schedule ND-1NR
NDES-T2-03	Spousal status change (MFS to MFJ between years)	Combine both spouses' prior-year ND liabilities for the joint 100% test
NDES-T2-04	High W-2 withholding shortfall	If W-2 withholding alone satisfies 100% prior-year, no estimates required; verify ND-source withholding (Box 17), not federal
NDES-T2-05	Newly self-employed (first year)	No prior-year ND-1 → only 90% current-year test available; build cushion into Q1
NDES-T2-06	Year-end Roth conversion or capital gain	Annualize installment method may eliminate Q1/Q2 underpayment for a Q4 event
NDES-T2-07	K-1 income from out-of-state PTE	Coordinate with ND credit for taxes paid to other states (Schedule ND-1CR) before sizing estimates
NDES-T2-08	Reasonable-cause waiver	Illness, casualty, disaster — attach signed statement to Form ND-1; outcome at Commissioner's discretion

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Section 13: Worked examples

Example 1 — Steady-income ND freelancer ($120,000 expected)

Facts. Single, full-year ND resident, Bismarck. Freelance software developer. TY 2024 ND tax was $1,420. Expects TY 2025 net Schedule C income of $120,000, federal taxable income of $97,500 after standard deduction and QBI. No W-2 withholding. No prior-year safe harbor issues.

ND tax computation (TY 2025 single, federal taxable income $97,500):

Bracket	Amount	Rate	Tax
$0 – $48,475	$48,475	0%	$0
$48,475 – $97,500	$49,025	1.95%	$956
TY 2025 ND tax			$956

Safe harbor:

• 90% × $956 (current) = $860
• 100% × $1,420 (prior) = $1,420
• Lesser = $860

But $860 < $1,000 threshold and prior-year exceeded $1,000? Prior year was $1,420. Threshold is on the expected current-year liability ($956) — at $956 the taxpayer is not required to make estimates (below $1,000) [VERIFY that threshold tests expected current-year ND tax rather than prior-year].

However, prudent practice is to pay anyway to avoid surprises. If the taxpayer elects to pay:

Installment	Date	Amount
Q1	April 15, 2025	$215
Q2	June 15, 2025	$215
Q3	September 15, 2025	$215
Q4	January 15, 2026	$215
Total		$860

Pay via ND TAP scheduled debits.

Example 2 — Self-employed with Q3 income spike (annualized method)

Facts. Single, ND resident, Fargo. Software consultant. TY 2024 ND tax was $3,200. Expects TY 2025 federal taxable income of $185,000 from a Q3 contract close. Income flow:

Cumulative through	FTI
Mar 31	$20,000
May 31	$35,000
Aug 31	$145,000
Dec 31	$185,000

TY 2025 ND tax (single, FTI $185,000):

Bracket	Tax
$48,475 – $185,000 → $136,525 × 1.95% = $2,662
TY 2025 ND tax	$2,662

Safe harbor:

• 90% × $2,662 = $2,396
• 100% × $3,200 = $3,200
• Lesser = $2,396 (required annual payment)

Regular installment method: $2,396 / 4 = $599 per quarter — would require $599 by April 15 even though only $20k of income has materialized.

Annualized installment method (using federal Schedule AI):

Annualized tax at each cutoff:

Period	Cumulative FTI	× Factor	Annualized FTI	ND tax	× 90% × Cum %	Required cum
Q1	$20,000	4	$80,000	$615	× 22.5%	$138
Q2	$35,000	2.4	$84,000	$693	× 45%	$312
Q3	$145,000	1.5	$217,500	(top bracket) ~$3,725	× 67.5%	$2,514
Q4	$185,000	1	$185,000	$2,662	× 90%	$2,396

Marginal installments under annualized method:

Q	Required cum	Marginal
Q1	$138	$138
Q2	$312	$174
Q3	$2,514	$2,202
Q4	$2,396 (capped)	$0 [VERIFY: cap mechanics in 2025 Schedule ND-1UT]

The annualization defers ~$2,000 of Q1/Q2 payment exposure into Q3, matching income timing. Attach federal Schedule AI to Schedule ND-1UT.

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

Facts. MFJ, both spouses ND residents. Primary spouse W-2 wages $280,000 with ND withholding of $4,800. Secondary spouse Schedule C net profit $60,000. TY 2024 ND tax was $5,900. Expects TY 2025 federal taxable income of $305,000, ND tax of $6,775.

Safe harbor:

• 90% × $6,775 (current) = $6,098
• 100% × $5,900 (prior) = $5,900
• Lesser = $5,900

Note: federal would apply 110% × $5,900 = $6,490 because prior-year AGI

$150,000. ND does NOT apply the 110% step-up [VERIFY] — the state safe harbor remains a flat $5,900.

Coverage check. Withholding $4,800 satisfies $4,800 of the $5,900 requirement. Remaining gap: $1,100.

Quarterly installments: $1,100 / 4 = $275 per quarter via ND-1ES.

Installment	Date	Amount
Q1	April 15, 2025	$275
Q2	June 15, 2025	$275
Q3	September 15, 2025	$275
Q4	January 15, 2026	$275

Federal Form 1040-ES installments will be larger because the 110% federal prior-year test produces a higher required annual payment. The state and federal calendars are aligned; the amounts differ.

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Section 14: Refusal catalogue

Refusal ID	Trigger	Response
R-NDES-01	Estate or trust estimated tax	"ND fiduciary estimated payments (Form 38-ES) are not covered by this skill — fiduciary rules differ from individual rules under N.D.C.C. Chapter 57-38."
R-NDES-02	Pass-through entity (PTE) estimated tax	"ND PTE estimated payments (Form 60-ES partnership / 58-ES S-corp) are not covered — PTE tax election rules require a separate skill."
R-NDES-03	Corporate estimated tax (Form 40-ES)	"Corporate estimated tax (Form 40-ES, Form 40-UT for corporate underpayment) is not covered — this skill is individual only."
R-NDES-04	Part-year resident or nonresident	"Part-year and nonresident estimated tax involves Schedule ND-1NR allocation; outside this skill. See nd-income-tax.md scope notes."
R-NDES-05	Farm-income averaging interaction	"Detailed farm-income averaging and the qualified-farmer safe harbor under N.D. Admin Code 81-03-04-02(3)(a)–(b) require specialist review."
R-NDES-06	Pre-TY 2024 or prior-year amended estimates	"This skill covers TY 2025 only. Older or amended quarterly computations require historical rate tables outside scope."
R-NDES-07	Reasonable-cause waiver drafting	"We will not draft the signed reasonable-cause statement — taxpayer or their representative must compose, sign, and submit."

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Section 15: Form mapping

Output	Form / Line	Notes
Each quarterly payment	Form ND-1ES voucher (one per installment) or TAP electronic	Paper voucher only required when paying by check
Annual reconciliation	Form ND-1, Line 27 (Estimated payments) [VERIFY current 2025 line number]	Sum of four quarterly ND-1ES payments
Withholding reconciliation	Form ND-1, Line 26 (ND income tax withheld)	W-2 Box 17 + ND-source 1099 withholding
Underpayment interest	Schedule ND-1UT, flows to Form ND-1 balance due line	Attach Schedule ND-1UT to ND-1
Annualized-method support	Federal Schedule AI attached to Schedule ND-1UT	ND does not publish standalone state annualization schedule
Federal coordination	Form 1040-ES (federal)	Same April/June/September/January 15 calendar
Federal annualized	Federal Form 2210, Schedule AI	Drives ND interest waiver per Admin Code 81-03-04-02(3)(c)

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Section 16: Sources and provenance

Statutes and regulations

• N.D.C.C. §57-38-62 — Estimated tax statute (individual) https://ndlegis.gov/cencode/t57c38.html
• N.D. Admin Code 81-03-04-01 — Estimated tax — general https://ndlegis.gov/prod/acdata/pdf/81-03-04.pdf
• N.D. Admin Code 81-03-04-02 — Payments of estimated taxes by individuals, estates, and trusts https://www.law.cornell.edu/regulations/north-dakota/N-D-A-C-81-03-04-02

Forms (TY 2025)

• Form ND-1ES — Estimated Income Tax — Individuals https://www.tax.nd.gov/sites/www/files/documents/forms/individual/2024-iit/28709-form-nd-1es-2025.pdf
• Schedule ND-1UT — Underpayment of Estimated Individual Income Tax (SFN 28704) https://www.tax.nd.gov/sites/www/files/documents/forms/individual/2025-iit/28704-schedule-nd-1ut-2025.pdf
• 2025 Individual Income Tax Booklet https://www.tax.nd.gov/sites/www/files/documents/forms/individual/2025-iit/2025-individual-income-tax-booklet.pdf

Payment portal

• ND Taxpayer Access Point (TAP) — https://apps.nd.gov/tax/tap

Federal counterparts

• IRC §6654 — Failure by individual to pay estimated income tax
• Form 1040-ES — Estimated Tax for Individuals
• Form 2210, Schedule AI — Annualized Income Installment Method

Verification markers in this draft

The following items are tagged [VERIFY] and must be confirmed against the current 2025 ND Tax Commissioner publications before reliance:

1. The $1,000 threshold on current-year expected liability (vs. prior-year)
2. Absence of a 110% high-income variant on the prior-year safe harbor
3. The 12% per-annum underpayment interest rate for TY 2025
4. The Bismarck mailing PO Box on the 2025 ND-1ES voucher
5. Current 2025 Form ND-1 line numbers (27 estimated, 26 withholding)
6. The annualized installment cap mechanic on Schedule ND-1UT
7. Reasonable-cause waiver administrative process
8. Absence of an electronic-payment mandate for individual estimated tax
9. TY 2025 PIT bracket schedule interaction with safe harbor (HB 1158 phase-down)

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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.

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