Difficult to generalise - it always rather depends upon the conditions, which does not help you much I realise. Today we have passed trucks and delivery vans with chains, but no actual cars. Our 4 wheel drive has winter tyres but at some stage and on two occasions we have slid rather alarmingly. However, wouldn't buy chains simply because of two small incidents. Hope this helps somewhat.

A set of chains set you back 50-100 swissies. Do you want to risk getting stuck - or slide off a mountain? I always have them with us, but, have never used them. It's just one of those things I hope I never have to use, but still carry it with me.

during my whole car driver life I had to mount chains only two times ... but it's better to have them in the trunk and not having to mount them than having to mount them and don't not have them in the trunk ... isn't it ?

PS: I warmly (and I really mean "warmly") advise you to carry also a pair of warm gloves (maybe an old pair of skiing gloves) and a small carpet: when you mount chains you have to lay on the frozen ground, and to handle frozen and wet pieces of metal (the chain themselves) ... at least it never happend to me to have to mount them during a warm and sunny summer day ... ;-) :-P

If you drive a rear wheel drive vehicle you need to take a set of chains in the boot just-in-case. Better and quicker ones to install are those not made of metals but made of synthetic cord reinforced w/metalic threads to get you out of a difficult stranded situation. One minute to install them and one minute to take them off when road conditions improve.

During winter I always have snow chains in the car. I have a 4x4 so 2 pairs. 

The general gist I am aware of here across the border in france is, chains are required to be carried in the car on roads marked with the blue sign. If you cause an accident or issues where the Gendarme come along, you can be prosecuted and fined if you do not have them. Also some areas, i.e. mont blanc tunnel wont let you through without them. 

''

France

Winter tyres compulsory? No.
Snow chains are a legal requirement and must be carried and used on roads displaying the relevant sign. Fines may be imposed if caught without. They are available for hire from most tyre specialists, or to buy from hypermarkets. Studded tyres are also permitted from November to April, on small vehicles.''

http://geneva.angloinfo.com/information/transport/driving/driving-in-ice-snow/

http://www.theaa.com/motoring_advice/overseas/snow-chains-winter-tyres.html

i have seen cars stuck in chamonix due to no chains, so its defo worth having chains if you venture to the hills.

you can get them cheaper online... just make sure you have the right size.

+1 for snow chains

Ok i admit we only needed them twice in 3 years but at those times im really glad we had them!

Will you crash into someone the third time?

ok sounds like I'll be buying some snow chains in the very near future - thanks for the advice! :)

- and a headlight, 2x aluminum blankets, a foldable snowshovel and some dark chocolate :) and maybe an old Nokia to call for assistance.

I'd also practise the snowchains a few times before that 1 a.m. snowstop in a -20°C blizzard.

sheila> Amazingly, all this stuff, including snowchains, is/was available at Aldi for next to nothing compared to the cost/inconvenience waiting for roadside assistance or injuring somebody. To not bring snowchains is just daft. The two slides told you nothing?

what the aluminium blankets are useful for ? :-O ?

yes, following the istructions sheet at 1 a.m. in a -20°C blizzard is not really comfortable ... but I guess that the effort of a dry-run would make sense only in case of long and frequent trips in the mountains ... anyway, modern chains are luckily quite easy to mount :-)

They are for the occasion, when you can't get free, after all, and have to wait in the car.

that's REALLY survival ! :-)

Forwards and backwards. When you get stuck going forward go backwards for a bit. Then go forwards again. Eventually you will get moving in a forward direction. Snow was deep enough to be up to the bottom of the doors here. I took the opportunity to play.

Experience dictates that snow chains are not essential. Driving at a reasonable speed and driving in a lower gear make sense. 

As a side note I counted at least seven vehicles working as snow ploughs, in the village where I live, earlier on. 

Yesyes, unless it's a light rear-wheel-drive and/or someone inexperienced. Forwards- and backwards is indeed good advice :)

My experience with chains is you don't need them often, but, when you do, you really really really need them.  They are magical.  How much is your car?  How much did you pay for snow tires?  Stop by Jumbo/Migro Brico/?? and buy a set that spend the winter in the trunk/boot.  Though it might be smart to scan over the directions once since the first time you'll put them on you'll be doing this in the dark, in the snow, under pressure, via the light from your phone...

If you drive a RWD you need snow chains on all wheels.

If you drive up to Flaine (in France), you often need chains. Sometimes the police will be there and stop the cars who don't have them. 

AWD or 4 Wheel drive yes, but RWD like FWD you only need them on the drive wheels. 

I agree with the safety kit - blankets, high energy foor, flashlight. Add to the list candles and matches - not for the romance but because a candle can give off enough heat in the car to make it somewhat bearable. 

As for driving in a lower gear, for starting on a slippery road, try starting in second gear, there will be less torque so it is less likely to spin the wheels. Reverse is the worst to start as the set up (ratio and radial cut gears gives more torque) 

I repeat, for RWD cars you need chains on all 4. If you understand how RWD differs from FWD the reason should be obvious.

No need to be rude Catalin, I am very familiar with rear wheel drive and with winter driving, having done so for over 25 years. Chains on the fronts will help with barking and steering, however given the moderate speed at which one drives with chains the second set is superfluous. 

So I was being rude for inviting you to think and use logic. So be it.

How you drive is your own concern but you shold not give improper advice to someone who is inexperienced in the matter. It's no use to be able to move forward if you have no steering.

Caitlin, 

With snow tires on the front and driving at a reasonable speed a rear wheel drive car does not need chains on the non drive wheels. 

I will not criticize your knowledge or make side remarks about your driving. However as a former police officer from a country where there is often 4 m of snowfall over a winter and freezing rain is not uncommon I was trained in driving in such conditions, including the use of chains. We did not use front wheel drive vehicles.