Different people vary widely in their susceptibility to seasickness (or any kind of motion sickness, for that matter). Bigger ships are definitely less prone to rocking and rolling than smaller ships. If you go on a megaship (Oasis-class, the biggest cruise ships in the world) it's VERY unlikely that you'll be seasick.

In the world of 2026 cruising, bigger ships generally provide a much smoother and more stable experience, making them significantly better for those prone to motion sickness. The physics behind this is simple: the larger the ship's mass, the more energy it takes for waves to rock it. Modern "mega-ships," such as Royal Caribbean’s Icon of the Seas or the Wonder of the Seas, are equipped with advanced, computer-controlled stabilizer fins that extend from the hull underwater to counteract rolling motions in real-time. These ships also utilize sophisticated weather-routing software to sail around major storms. While no ship is entirely "motion-proof" in a massive hurricane, you are far less likely to feel the "pitch and roll" on a 250,000-ton vessel than on a smaller boutique ship or an older liner. If you are extremely sensitive, the 2026 expert consensus remains to book a cabin on a lower deck near the center of the ship (the "fulcrum"), where the movement of the ocean is felt the least, ensuring a comfortable journey even in moderate seas.