Compliance · 🇰🇷 South Korea Live mandate

South Korea — NTS e-Tax invoice system

NTS e-Tax invoice · universal corporate clearance since 2011 — regulator: National Tax Service (NTS). Facts last refreshed: 2026-05-05.

Coverage model

Flowie operates a registered Peppol Access Point in this jurisdiction directly where we hold national accreditation, or via a vetted local partner registered with the in-country regulator where on-the-ground presence is required (KSeF, SDI intermediario, ZATCA service-provider, etc.). Either way, you call the same POST /v1/documents/send.

TL;DR

Korea introduced its e-Tax invoice regime in 2011 — one of the earliest national CTC mandates anywhere.
Mandatory for all corporations; sole proprietors are absorbed by descending revenue threshold (KRW 300m → KRW 100m → KRW 80m since Jul 2024).
Invoices must be issued, signed, and reported to NTS via the HomeTax portal within 1 day of issuance.
Format: NTS-mandated XML; HSM-issued certificate signs each invoice.
No Peppol, no overlapping mandate. Stable — no announced changes for 2026.

Deadlines

Date	Who	What
2011-01-01	All corporations	e-Tax invoice mandatory.
2014-07-01	Sole proprietors > KRW 1 bn turnover	Threshold rolled out.
2019-2023	Threshold steps down: KRW 300m → 100m	Sole proprietors absorbed.
2024-07-01	Sole proprietors > KRW 80m turnover	Current threshold — unchanged for 2026.

Background

South Korea's e-Tax invoice system, launched in 2011, is one of the earliest and most comprehensive national CTC programmes in the world. Operated by the National Tax Service (NTS) via the HomeTax portal, the regime requires every corporation — and any sole proprietor with the previous-year turnover above KRW 80 million — to issue invoices in the NTS-mandated XML schema, sign them with an HSM-issued tax-purpose certificate, and transmit to NTS within 1 day of issuance.

Late or non-issuance attracts penalties (typically 1% of the invoice amount). Korea was originally proud that e-Tax pre-dated SAF-T and continuous-control regimes elsewhere; the system has been stable for over a decade with the only ongoing change being progressive lowering of the sole-proprietor threshold (most recently to KRW 80m in July 2024).

There is no Peppol involvement, no plan to migrate, and no announced changes for 2026.

Format profile

NTS XML schema (national, not UBL).
Seller and buyer BRN (Business Registration Number, 10 digits) mandatory.
Tax-purpose certificate issued by KISA-accredited CA required to sign each invoice.
Issuance + transmission must complete within 1 day of the invoice issue date; subsequent days incur penalties.

Required fields

seller.brnstring (10 digits)required

Korean Business Registration Number — formatted as NNN-NN-NNNNN.
buyer.brnstring (10 digits)required for B2B

Buyer BRN.
seller.taxCertificatePKCS#12required

KISA-accredited tax-purpose certificate; binds the seller's NTS identity to invoice signatures.

Public sector (B2G)

Combined private + public flow — no dedicated B2G hub for this country.

B2B reporting / clearance

NTS HomeTax — Issuance, signing, and reporting of every corporate-issued tax invoice within 1 day of issue.

Lifecycle status	Reported as
`issued`	Invoice signed and registered with NTS.
`late`	Issued but reported beyond 1 day — penalty applies.

Error codes

Generic Peppol BIS schematron error codes apply (BR-*, EN16931-*); no country-specific overlays.

Testing in sandbox

What you want to test	How
South Korea happy path	Sender BRN `123-45-67890`, recipient any KR BRN in Flowie sandbox.

FAQ

Is there a Peppol path in Korea?

No. Korea operates a fully national stack via HomeTax; Peppol is not adopted.

References

Primary sources (government / regulator / standards body):

National Tax Service (English) — Tax authority.
HomeTax portal — e-Tax invoice issuance + reporting.

Industry analyses (vendor trackers — useful for cross-referencing):

Sovos · South Korea e-Tax Invoice — Industry analysis — long-running CTC.
EDICOM · South Korea e-invoicing — Industry tracker — sole proprietor thresholds.