Sefer İptal is an independent tracker and explanatory website for IDO ferry and sea-bus sailings in the Sea of Marmara. It offers sailing checks, source explanations and historical archive analysis in Turkish and English. It is not the official IDO website and is not affiliated with IDO.
This page is a short reference for journalists, researchers and readers citing the site. Use sailing search for live status. The historical counts on this page end on 14 September 2026; they are not a live total.
A finding you can cite
Of 208,801 archive records dated 21 February 2018–14 September 2026, 21,772 have a cancelled primary status: 10.4%. The denominator includes all archive records, including 5 unresolved records. The other 187,024 records have a completed status. This is not a cancellation rate for IDO’s entire history or the probability that a particular sailing will be cancelled today.
Annual chart and count table
Open PNG figure · Open SVG figure
| Year | All records (denominator) | Cancelled records (numerator) | Cancellation share |
|---|---|---|---|
| 2018 (partial) | 26,044 | 1,390 | 5.3% |
| 2019 | 29,080 | 1,017 | 3.5% |
| 2020 | 27,140 | 7,202 | 26.5% |
| 2021 (43 empty dates) | 22,200 | 1,712 | 7.7% |
| 2022 | 26,911 | 4,606 | 17.1% |
| 2023 | 20,140 | 1,832 | 9.1% |
| 2024 | 22,683 | 2,204 | 9.7% |
| 2025 | 20,015 | 780 | 3.9% |
| 2026 (partial) | 14,588 | 1,029 | 7.1% |
| Total | 208,801 | 21,772 | 10.4% |
Method and interpretation limits
The calculation uses unique archive rows and the primary status field; it does not apply weather-study exclusions. Status fields disagree in 850 records, which remain in the denominator. First and last observations are not route opening or closure dates. Original and replacement voyage records may be different observations; record counts do not guarantee counts of physical departures.
The annual bars include different route mixes and observation periods. 2018 starts on 21 February; 2026 ends on 14 September. The 43 empty dates in 2021 do not establish that all sailings on those days were cancelled. A high share alone does not establish weather, the pandemic, demand or any other cause. Seats reported sold are not passengers who boarded. Full methodology and data limits.
Suggested citation
Sefer İptal, “Press and research reference”, 17 September 2026. Cancellation share calculated from the IDO API archive: 21,772 / 208,801 = 10.4%; period: 21 February 2018–14 September 2026. https://seferiptal.com/en/press/
When sharing a figure or finding, retain its period, denominator, partial-year markers and limitations. Credit Sefer İptal for the chart and analysis and IDO for the underlying sailing records; link to the specific page. Do not imply operator endorsement or a live sailing guarantee. This page offers no downloadable raw archive or CSV/JSON data files.
Press questions and corrections
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