The world's ten biggest cruise ships by gross tonnage, led by Royal Caribbean's record-setting Icon-class trio.
Quick answer: 1. Icon of the Seas, 2. Star of the Seas, 3. Legend of the Seas, 4. Utopia of the Seas, 5. Wonder of the Seas, 6. Symphony of the Seas, 7. Harmony of the Seas, 8. Oasis of the Seas, 9. Allure of the Seas, 10. MSC World America.
Modern cruise ships are among the largest passenger vessels ever built, and the race for the "world's biggest" title has been dominated by a handful of operators pushing gross tonnage ever higher. This list ranks the ten largest ocean-going cruise ships in service (or newly delivered) as of mid-2026, measured by gross tonnage — the standard measure of a ship's total internal volume. It's for cruise fans, ship-spotters, and anyone curious about just how big these floating resorts have become. Royal Caribbean's Icon and Oasis classes take nine of the ten spots, with MSC Cruises' World America rounding out the list as the largest ship from any other operator.
The lead ship of Royal Caribbean's Icon class and the largest cruise ship in the world by gross tonnage. It entered service in January 2024 and, tied on tonnage with its two sisters, ranks first as the earliest in service.
The second Icon-class ship, identical in gross tonnage to Icon of the Seas. It entered service in 2025 and ranks just behind its older sister on the tie-breaker.
The third Icon-class ship, sharing the same 248,663 GT as its sisters. It was delivered in June 2026 and entered service in 2026, taking third on the entry-date tie-breaker.
The largest of Royal Caribbean's Oasis-class ships and the fourth-largest cruise ship overall. It entered service in 2024.
The fifth Oasis-class ship, launched in 2022. It was briefly the world's largest cruise ship before the Icon class arrived.
The fourth Oasis-class ship, which entered service in 2018 and held the largest-cruise-ship title until Wonder of the Seas overtook it.
The third Oasis-class ship, delivered in 2016 and marginally larger than the original two Oasis vessels.
The original Oasis-class ship, launched in 2009. It redefined mega-ship scale and held the world's-largest title for years.
The second Oasis-class ship and sister to Oasis of the Seas, entering service in 2010.
The largest non-Royal Caribbean cruise ship, a World-class vessel operated by MSC Cruises. It entered service in 2025.
| # | Name | Operator | Length (m) | Max passengers | Year in service |
|---|---|---|---|---|---|
| 1 | Icon of the Seas | Royal Caribbean International | 364.75 | 7600 | 2024 |
| 2 | Star of the Seas | Royal Caribbean International | 364.83 | 7600 | 2025 |
| 3 | Legend of the Seas | Royal Caribbean International | 364.84 | 7600 | 2026 |
| 4 | Utopia of the Seas | Royal Caribbean International | 361.12 | 5668 | 2024 |
| 5 | Wonder of the Seas | Royal Caribbean International | 362.04 | 6988 | 2022 |
| 6 | Symphony of the Seas | Royal Caribbean International | 361.01 | 6680 | 2018 |
| 7 | Harmony of the Seas | Royal Caribbean International | 362.12 | 6687 | 2016 |
| 8 | Oasis of the Seas | Royal Caribbean International | 360 | 6771 | 2009 |
| 9 | Allure of the Seas | Royal Caribbean International | 360 | 6780 | 2010 |
| 10 | MSC World America | MSC Cruises | 333.3 | 6762 | 2025 |
Ships are ranked by gross tonnage (GT), the standard measure of a ship's total internal volume, as recorded by the operator and Wikipedia's List of largest cruise ships. Rank 1 is the highest gross tonnage. Ships tied on gross tonnage — the three Icon-class sisters all measure 248,663 GT — are ordered by entry-into-service date, earliest first. Inclusion is limited to ocean-going passenger cruise ships that are in service (or newly delivered) as of mid-2026. Fact figures (operator, overall length in metres, maximum passenger capacity, and year entering service) trace to the same sources.
Icon of the Seas, operated by Royal Caribbean International, is the largest cruise ship in the world by gross tonnage at 248,663 GT. It entered service in January 2024 and shares that tonnage with its Icon-class sisters Star of the Seas and Legend of the Seas.
Cruise ships are ranked by gross tonnage (GT), a measure of the ship's total enclosed internal volume rather than its weight. This list uses gross tonnage as recorded by operators and Wikipedia's List of largest cruise ships.
Icon of the Seas, Star of the Seas, and Legend of the Seas are near-identical sister ships built to the same design, so they share a gross tonnage of 248,663 GT. On this list they are ordered by entry-into-service date, with the earliest ranked first.
Royal Caribbean International dominates the top of the list, holding nine of the ten spots through its Icon and Oasis classes. MSC Cruises' World America, at 216,638 GT, is the largest cruise ship from any other operator.