We stayed just one night in the cheapest cold room. It's expensive and I would suggest you stay somehere else such as the wonderful Lappeasuando Lodge in Gallivare to do an trips like Husky Sledging. ( Icehotel overnight sledging price currently 5950SEK 3pm to 11am , Lappeasuando Lodge price currently 2910SEK for 10am to 4pm!! ( they do transfers to Ice Hotel as well)). We slept well but we had spent a night earlier in the week in the igloo we had built which was about -17! If you worried about being cold go for single sleeping bags rather than doubles as they are easier to keep warm in.
The service was okay and the atmostphere in the ice bar in the evening was a bit dead. It was also a bit crowded in the morning when everyone is trying to get to their locker.
The nearby Homestead restuarant is excelent - the food is of such a high standing you don't mind paying Swedish prices.
In conclusion - this is definately a place worth visiting.

I can't speak highly enough of this place. Having stayed for three nights, one in an ice room and two in the warm accommodation, I can honestly say that the Ice Hotel is one of the best places I've ever experienced. The staff are friendly and welcoming, and the hospitality is second to none. Watching the Northern Lights on the viewing platform on the roof of the Ice Hotel was simply magical.

This is one of the things you definitely need to do if you are visiting Kiruna in Sweden, the experience of being in a hotel where everything is made of ice is extraordinary, I didn't spend the night because I was traveling solo and I preferred to spend the night at Reindeer Lodge, you can stay in the cabins outside of the ice hotel if you want more comfort too. Each year the hotel is rebuilt from scratch and new artists participating in the construction of the rooms. The bar it's pretty awesome too, but it only serve vodka

There are three room types inside:
1 - Single: Only one bed in four walls of ice.
2 - Medium: Bed, nightstand, table with two chairs in four ice walls.
3 - Main rooms: These are the rooms that are designed by artists from around the world and are perfect for honeymooners or couples in general. (but are more expensive and you have to book well in advance).

My daughter (13) and I visited this hotel in Jan this year.We loved the experience- we did not sleep over in an Ice room because we found it way too expensive for our budget and slept over in a warm room which I am glad we did, as people mentioned it really was cold and they couldnt get much sleep in and the realization of no ablutions(obviously) in the room put me off completely.The warm Kamos rooms were comfortable, and roomy.The Ice rooms with their unique themes were incredible;the ice sculpting was fun - having breakfast across the street was a bit of a bother.Walking into town to a supermarket is a bit too far for small children.