Domestic B2B and B2G. All corporations regardless of size; sole proprietors whose prior-year per-place-of-business supply value (taxable + exempt) ≥ KRW 80,000,000, with the obligation starting on 1 July of the following year. Once in scope, always in scope. Effectively resident-only. B2C is covered by cash receipts (현금영수증), not e-Tax Invoice.
The '24-hour transmission rule' is a paraphrase — the statutory rule is transmission by the day AFTER the issuance date (calendar days), not a rolling 24-hour clock. 'Issued' means the file reached the buyer's inbox or the NTS system; an SMS or download link is not issuance. A separate document type (전자계산서) applies to VAT-exempt supplies and teams routinely wire only 세금계산서 and miss it. Monthly-summary invoices may be issued up to the 10th of the following month. Beware the Pagero/Thomson Reuters Korea page: it is dated Nov 2022, still shows the superseded KRW 100m threshold, and ranks highly in search.
3 of 4 are primary sources. Mandate dates move — treat this page as a starting point and confirm against the primary source before committing a plan.
A page is a starting point. A scoped analysis gives you the specification, the mapping and the effort — in weeks, not quarters.
