Korean Cash Receipt Penalty Calculator | 5 / 10 Days and 20% / 10%

Unissued balance, 5 / 10-day base dates, penalties and reductions by transaction
Transaction / status	Unissued KRW	Anonymous 5-day base	Reduction 10-day base	Penalty KRW	Reduction KRW
Transaction 1 Conditions or timing need review Anonymous issuance using the NTS code · 2026-09-11	1,000,000 KRW	2026-09-06	2026-09-11	Review needed	Review needed

Start with the transaction when a cash receipt is missing

This calculator helps business owners and bookkeepers review unissued Korean cash receipts using 2026 rules.
A sale may appear correctly in the ledger and bank statement while its cash receipt remains missing.
Check the mandatory-issuance classification, the full transaction value, the amount of cash received and the actual issuance dates before estimating a penalty.
The calculator separates the amount already issued on time from the outstanding balance, then compares the selected corrective action against baseline exposure.

Korea-specific rules and KRW

These results use Korean law, Korean won and the same calculation functions as the Korean page.
They are transaction review scenarios, not a tax assessment, an accepted filing or a completed receipt issuance.
A customer declining a receipt does not by itself remove the obligation for a qualifying mandatory-industry transaction.

Reviewing bank receipts and issuance approvals regularly is especially useful after a bookkeeping handover or when receipts have been issued in batches.
The goal is to identify the next action for each transaction before totals obscure an unresolved item.

Industry and full transaction value determine the threshold

KRW 100,000 including VAT

Income Tax Act Article 162-3(4) and Corporate Tax Act Article 117-2(4) require issuance for qualifying mandatory-industry supplies with a transaction value of at least KRW 100,000 including VAT when payment is received in cash, even without a customer request.
Exactly KRW 100,000 meets the threshold.

Verify the actual industry

Check Annex 3-3 of the Enforcement Decree of the Income Tax Act.
A business name or a note in the form cannot determine its legal classification.
For businesses operating several activities, check which activity supplied this particular transaction.

For a KRW 1,000,000 transaction paid with KRW 950,000 by card and KRW 50,000 in cash, the threshold is assessed using the full KRW 1,000,000.
Assuming a qualifying mandatory industry, the unissued cash portion can therefore be relevant even though the cash payment alone is below KRW 100,000.
A full transaction value of KRW 99,999 is outside this mandatory-issuance model.

Outside scope does not mean that no cash receipt obligations exist.
Rules for a customer request and refusal by an ordinary registered merchant must be checked separately.
Non-registration penalties and consumer whistleblower rewards are also outside this calculator.

The 5-day issuance period differs from the 10-day reduction

5 days for anonymous issuance

Income Tax Act Enforcement Decree Article 210-3(13) and Corporate Tax Act Enforcement Decree Article 159-2(8) provide for anonymous issuance within 5 days after cash receipt.
The NTS designated code is 010-000-1234.
An otherwise valid, timely anonymous-issuance scenario shows a zero penalty for the modeled outstanding balance.

10 days for an accidental omission

The standard penalty for mandatory nonissuance is 20% of the unissued amount.
Where an error or omission is corrected by voluntary reporting to the competent tax office or voluntary issuance within 10 days after receiving payment, the rate is 10%.
That halves the standard penalty; it is not a complete exemption.

The form distinguishes anonymous issuance, issuance using customer details, voluntary reporting and no action.
It does not extend the 5-day anonymous-issuance treatment to every late receipt issued using customer details.
Named issuance on the cash receipt date is treated as timely; later named issuance is evaluated separately.
A date within 10 days is insufficient by itself: the error-or-omission condition must also be verified.

Prepare the amounts and dates

Full transaction value: enter the VAT-inclusive value of the actual transaction.
Do not split the legal transaction threshold merely because payment arrived in installments.
Cash received in this installment: enter only the actual cash or bank payment for this receipt of funds.
Keep card payments out of this field while retaining them in full transaction value.
Amount already issued on time: deduct only valid, timely issuance.
Do not deduct late-issued receipts here, as that would erase their exposure; model their actual issuance date instead.
Action and date: select the action for the entire outstanding balance and its actual or planned date.
For no action, enter the date of your review.

Reconcile the supply date, cash receipt date and issuance or reporting date against documents.
A payment received before supply, including an advance payment, requires separate timing review in this general model.
Supply and receipt dates must be in 2026; action dates can extend to January 10, 2027 for year-end 2026 receipts.
This extension models 2026 receipts under the same rules and does not certify the law for new 2027 transactions.

Calculate the unissued balance and penalty

Avoid subtracting the same amount twice

Unissued balance = cash received − receipts issued on time
Baseline exposure = unissued balance × 20%
Qualifying reduced penalty = unissued balance × 10%
Reduction = baseline exposure − selected action penalty

If KRW 1,000,000 was received and KRW 400,000 was validly issued on time, the remaining base is KRW 600,000.
Baseline exposure is KRW 120,000; qualifying correction within 10 days produces a KRW 60,000 penalty.
If the KRW 400,000 receipt was also issued late, it cannot be treated as timely issuance and the scenario must be rebuilt from its actual history.

Use whole KRW inputs.
The calculator floors fractional KRW separately for each row as a comparison convention; final tax-return rounding may differ.
It does not automatically add other taxes or local surtaxes.
The status explains whether a zero or reduced amount arises from timely issuance, the verified invoice exception or the 10-day reduction.

Worked example: KRW 1,000,000 at 5, 10 and 11 days

Assume a verified mandatory-industry transaction paid entirely in cash on September 1, 2026, with no amount already issued on time.
The unadjusted 5-day base date is September 6 and the 10-day base date is September 11.
The following scenarios do not automatically adjust for holidays or individual extensions, and the reduced-rate example assumes a verified error or omission.

Issuance timing scenarios for KRW 1,000,000 received September 1, 2026
Action	Days	Penalty KRW	Reduction KRW
Anonymous issuance September 6	5	0	200,000
Accidental omission corrected September 11	10	100,000	100,000
Voluntary issuance September 12	11	200,000	0

The verified example button treats these as three separate transactions and shows KRW 300,000 in total.
The three rows illustrate timing differences; do not register the same real receipt of cash three times when preparing your own ledger.

Build a transaction date review sheet

Reconcile bank receipts with cash receipt approval records.
Check whether apparent gaps are cancellations or duplicate approvals.
Verify the transaction industry using the official annex, then separate full transaction value from this cash installment.
Leave classification unverified where evidence is missing.
Enter only timely-issued amounts as deductions and select an action for the entire remaining balance.
After a planned issuance actually occurs, reconcile its approval date.
Calculate the dates and penalties, then resolve rows marked for review.
Check the facts and procedure promptly where the base date is approaching.
Save the CSV together with contracts, payment records, approval numbers and the correction explanation.
Recalculate after changing inputs so the exported result remains current.

Use the ledger for installments and bookkeeping checks

Record each receipt of cash

If deposits and balances were received on different dates, use separate receipt rows.
Retain the full transaction value in each row but enter only that installment of cash.
Do not repeat amounts already included elsewhere.
Advance payments before supply still require separate timing review.

Check gaps before closing the books

Record the bank payment date, approval date and availability of customer details together.
Keep the reason supporting an error-or-omission classification.
A choice in this calculator does not replace evidence or the actual review of eligibility for a penalty reduction.

One row applies one action and date to its entire unissued balance.
A complex history involving several correction dates, named and anonymous receipts, cancellations or reissuance may not fit that assumption.
Reconcile approval records first and confirm an appropriate allocation with your tax adviser where necessary.

Distinguish zero, review needed and outside scope

Unverified transactions are not zero

Unverified industry, relevant error-or-omission conditions or special timing rules suspend the result.
If any row needs review or is outside scope, the calculator withholds a complete total and labels the calculable subtotal explicitly.
An unresolved transaction is not silently removed from your exposure.

The statutory invoice exception requires both a supply to a registered business and lawful issuance of the applicable invoice or tax invoice.
Do not select it merely because the customer is a business.
Health-insurance benefits, mixed supplies, platform transactions and other special cases need separate review; the calculator does not automatically exempt them.

Base dates count calendar days starting after receipt.
Check applicable time computation and deadline provisions under Framework Act on National Taxes Articles 4 and 5 and Civil Act Article 157.
The calculator does not authorize extensions for weekends, public holidays, individual relief or system outages.
Select timing review when these provisions affect the transaction instead of assuming that issuance can be delayed.

Frequently asked questions

Must I issue a receipt without a customer request?

For a qualifying mandatory-industry transaction worth at least KRW 100,000 including VAT and paid in cash, issuance is required without a request.
Check NTS anonymous issuance guidance when the customer declines a receipt or their details are unavailable.

Does anonymous issuance within 5 days incur the reduced 10% penalty?

An otherwise valid and timely anonymous issuance within the 5-day base period shows zero in this model.
The 10-day reduction concerns an existing nonissuance violation caused by an error or omission, so these are different provisions.

Is every correction within 10 days automatically reduced?

No.
Nonissuance must have resulted from an error or omission.
The date alone cannot establish this condition; leave it unverified until the facts have been checked.

Does voluntary reporting also create the receipt?

No.
Reporting to the competent tax office is a statutory route to the reduction, but filing acceptance does not itself generate a cash receipt.
Report-only rows retain an outstanding issuance balance, so verify receipt issuance or correction separately.

Can I deduct an amount already issued late?

The deduction field is only for valid issuance completed on time.
Deducting a late-issued amount can hide its penalty exposure.
Model that late issuance using its actual date and action instead.

Does no action mean I must pay the displayed amount immediately?

The 20% shown for no action is baseline exposure if the balance remains unresolved, not an assessed amount currently due.
Check whether timely issuance or reduction is still possible and compare the action scenario.

Does a transaction below KRW 100,000 have no obligations?

It is outside the mandatory-issuance penalty modeled here.
Ordinary merchant rules for customer requests and refusal can still matter.
Do not use an out-of-scope result as proof of exemption.

Are the rates different for an individual and a corporation?

For the obligations modeled here, Income Tax Act Article 81-9 and Corporate Tax Act Article 75-6 both provide a standard 20% rate and a qualifying 10% rate.
Tax-return treatment and other penalties still need separate review.

Official sources and verification date

Current legislation was checked directly through the National Law Information OPEN API on September 14, 2026.
The relevant Income Tax Act and Corporate Tax Act penalty provisions use the January 1, 2026 effective texts.
The current Income Tax Act Enforcement Decree is MST 286211 and the Corporate Tax Act Enforcement Decree is MST 283635.
The anonymous-issuance citation is Article 210-3(13), reflecting the 2026 paragraph renumbering.
Recheck industry classifications, paragraph numbers, reduction periods and exceptions when legislation changes.

Reconcile the missing receipts and complete the actual procedure

Compare the dates and amounts against the contract, payment records and issuance approvals, then confirm the appropriate issuance or reporting procedure.
Hometax issuance and voluntary reporting to a tax office may be separate steps; retain their respective approvals and acknowledgments.
Resolve transactions marked for review and recalculate before relying on a complete scenario total.

Recalculate transaction penalties and base dates

Cash Receipt Nonissuance Penalty and Voluntary Issuance Calculator

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