No, not all vessels have IMO numbers.
Here’s a breakdown:
✅ Vessels that do have IMO numbers:
The IMO number (International Maritime Organization number) is a unique identifier assigned by IHS Markit under the authority of the IMO. It is mandatory for:
- Commercial ships ≥ 100 GT involved in international voyages
- Cargo ships ≥ 300 GT in international service
- Passenger ships, regardless of tonnage, in international service
- Mobile offshore drilling units (MODUs)
- Fishing vessels ≥ 100 GT, if flagged by a country that applies IMO’s voluntary scheme
❌ Vessels that do not have IMO numbers typically include:
- Small recreational boats (e.g., yachts, sailboats under 100 GT)
- Domestic-only vessels operating within a single country’s waters
- Warships and naval auxiliaries
- Inland waterway vessels
- Fishing vessels in many countries (though this is changing)
- Smaller barges or tugboats under 100 GT and not in international waters
Summary:
If the vessel is large and commercial, especially operating internationally, it almost certainly has an IMO number. For smaller, domestic, or non-commercial vessels, it likely does not.