Every Antarctica operator will send you a detailed packing list before your voyage. Some are comprehensive to the point of overwhelming. All of them will tell you the same fundamental thing, because the same fundamental thing is true: dressing for Antarctica is about layers, not volume.
The three-layer system
Expedition clothing is built around three layers that work together.
Base layer
The layer against your skin. Its job is to move moisture away from your body and keep you dry. Merino wool and synthetic fabrics do this well. Cotton does not. When cotton gets wet, whether from sweat or spray, it stays wet and gets cold. Leave the cotton at home.
Mid layer
The insulating layer. Fleece and lightweight down both work well. This is the layer you add and remove most frequently as you move between the ship and the outdoors, between active walking and standing still at a landing site. Plan to have at least one mid-layer that’s easy to put on and take off quickly.
Outer layer
The shell that keeps wind and water out. Waterproof and windproof, not merely water-resistant. This is non-negotiable. You will get wind and spray in Zodiacs. You might get snow. Your outer layer needs to handle all of it without letting any of it through.
Extremities matter more than you think
Your hands, feet, and face are where you will feel the cold first and most acutely. Good waterproof gloves or mittens, warm socks, and a hat that covers your ears are not optional. A neck gaiter or balaclava is useful on colder days and windy Zodiac rides. Sunglasses or goggles are essential. The Antarctic sun reflecting off ice and snow is intense, and the UV exposure at this latitude is higher than most travelers anticipate.
Your operator will guide you
Every operator provides specific gear guidance tailored to their itinerary, season, and the activities included. Some send a detailed list with recommended brands and where to buy. Some offer their own gear guides. Read what they send. They know their ships, their landings, and their conditions better than any generic packing list can account for.
Use this article as an orientation. Use your operator's list as your checklist.