Almost everyone has a December year-end
Korean listed companies overwhelmingly close their books on 31 December, so the reporting calendar is unusually synchronised. Quarterly and half-year reports are due within 45 days of the period end and the annual report within 90 days, which puts the heavy weeks in mid-May, mid-August, mid-November and the last week of March. A company with a different fiscal year-end states it in its filings.
Results arrive twice
Many companies publish a provisional results filing before the audited statements — revenue, operating profit and net profit, with the year-earlier figures alongside. Those numbers can move when the full report is filed, and a large difference triggers an amended filing. The rankings on this site use the figures in the periodic reports rather than the provisional release, so they may differ from the headline a company put out earlier.
Operating profit is the line Korea watches
Korean coverage leads with 영업이익 (operating profit) rather than EPS. It sits below revenue and above the financial items, so it shows what the core business earned before interest, tax, equity-method results and asset disposals. A company can post an operating loss and a net profit in the same quarter by selling an asset, so check which line moved.
Consolidated or separate
Filings carry both consolidated (연결) and separate (별도) statements. Consolidated includes subsidiaries and is the default for comparison; separate covers the parent alone. Holding companies are the trap here — on a separate basis their revenue is small while operating profit can include large equity-method income from affiliates, producing margins that look impossible. We label which basis each table uses and leave out margin figures that are not meaningful.
The fourth quarter is calculated, not filed
Most companies do not file a standalone fourth quarter; the annual report covers the full year. Q4 is therefore derived as the full year minus the nine-month cumulative figures, and we mark those rows as derived. Korean companies also tend to concentrate year-end costs — performance pay, severance programmes, asset write-downs — in the fourth quarter, so it often looks weaker than the rest of the year.
Compare with the same quarter a year earlier
Sequential comparisons are misleading in a market this seasonal: retail and travel peak in specific quarters, construction revenue follows completion schedules, and memory follows its own cycle. Korean reporting compares with the same quarter of the previous year, and so do the growth figures and screener signals on this site.
Units and currency
Figures are filed in Korean won, usually written in units of 억 (100 million) or 조 (1 trillion) in coverage. One trillion won is roughly 700 million US dollars at recent rates, but we do not convert — exchange rates move and the filings are in won. Share counts and per-share figures come from the same reports.
Where to read them
Quarterly revenue, operating profit, net profit and the operating margin for each listed company are on its page, with rankings by quarter on Korean earnings rankings and the provisional filings on latest filings. Every figure links back to the original document on DART.
This is an explanation of rules and procedure, not investment advice. Rules reflect September 2026 and can change; check the filing and your broker before acting. Corrections: contact us.