Can I get by with just a heavy winter coat?

No. A heavy coat is bulky and often not waterproof. The Icelandic wind will cut right through non-technical gear, and you'll overheat when hiking and freeze when standing still.

Do I really need rain pants?

Yes. When visiting places like Seljalandsfoss or Skógafoss, the mist will soak your jeans through in two minutes. Waterproof overtrousers are the only way to stay dry.

Mastering the Layering Game: Packing for Iceland

Pack for four seasons in a single day by using a three-layer system: a synthetic base layer, an insulating mid-layer, and a fully waterproof/windproof outer shell. Avoid cotton entirely, as it holds moisture and keeps you cold once it gets damp.

Prioritize your base layers. Bring two sets of merino wool or high-quality synthetic thermal tops and bottoms. These wick sweat away from your skin, preventing you from getting chilled when you stop moving.
Choose the right insulation. Carry a lightweight down or synthetic 'puffy' jacket for warmth and a fleece or wool sweater as a secondary mid-layer. You should be able to wear both at once if temperatures drop near freezing.
Invest in a high-performance shell. Your outer layer must be 100% windproof and waterproof. Look for Gore-Tex or similar technical membranes with a high waterproof rating (at least 15,000mm). Do not rely on 'water-resistant' hoodies.
Protect your extremities. Pack two pairs of waterproof hiking boots that are already broken in. Bring three pairs of thick wool socks, a windproof beanie, and gloves that allow you to operate a camera or phone screen.

Can I get by with just a heavy winter coat?: No. A heavy coat is bulky and often not waterproof. The Icelandic wind will cut right through non-technical gear, and you'll overheat when hiking and freeze when standing still.
Do I really need rain pants?: Yes. When visiting places like Seljalandsfoss or Skógafoss, the mist will soak your jeans through in two minutes. Waterproof overtrousers are the only way to stay dry.