From www.asloca.ch

J’ai le droit de sous-louer mon logement, pour autant que j’indique à mon bailleur les conditions de la sous-location.

Oui, mais vous devez solliciter une autorisation écrite du bailleur pour pouvoir sous-louer. Celui-ci ne peut pas la refuser, sauf justes motifs, si vous lui communiquer les conditions de la sous-location (identité du sous-locataire, montant du loyer de sous-location). Encore faut-il que les conditions de sous-location ne soient pas abusives (ne sous-louez pas le double du prix de la location principale !). En cas de refus injustifié du bailleur, il est nécessaire de saisir l’autorité de conciliation pour faire constater que les conditions de sous-location ne sont pas abusives.

En tant que locataire principal, vous restez tenu envers votre bailleur de toutes les obligations découlant du bail; vous répondez entièrement des actes du sous-locataire (paiement du loyer, dégâts au logement, comportement dans l'immeuble). Assurez-vous que celui-ci possède une assurance responsabilité civile, faites lui signer un contrat de bail écrit et faites établir une garantie-loyer auprès d'un établissement bancaire (garantie dont le montant devra figurer dans le contrat écrit).

In English:   You can sublet, but you have to give the owner notice in writing along with contract.

Thanks Michelle but my question was "Do i have to give the regie a reason as to why i want to sublet?"

Give the regie a reason? You wish to sublet and you kindly ask for being authorized âccording to rules and principle. The reader of your letter assumes you sublet because you are away for a limited time, say ca. 6 3-6-9 months...No real reason to post but you do specify you like your flat and wish to keep it when you come back. Nothing more. Caution though, if your idea is to sublet more than a year then regie will likely start asking questions.

No, the only things that you have to communicate are the terms of your contract with the subtenant.

I've got a model letter for subletting. If you mp me your email adress, I'll send you a copy of it. I also have a model sublet contract, but on paper; if you need a copy, send me your mailing adress as well.

Best

You should be aware that the regie will probably answer with a letter agreeing to the sublet with conditions, such as that the sublet can only be for a year. 

To make sure that these conditions are indeed legal, you should take the regie letter to ASLOCA, the national renters' association.

Thanks everyone, i have sent the letter so lets see ;-)

Hi Everyone 

I am trying to find a sample letter in Fr for requesting to sublet my appertment.

Can anyone help?

Many thanks

http://www.ums.ch/infos-offreur/contrat-sous-location-modeles-check-liste/

Hi Gul.

In Swizertland ,you have to ask from the owner the permission to sublet your appartment ,and this is a web site who proposes you a sample of a letter you have to send to the owner http://droit-finances.commentcamarche.net/faq/3162-modele-de-lettre-location-autorisation-de-sous-location ,hoping that this helps you !

Regards

Avoid using French sample letters, as they refer to French law and regulations, unknown to Swiss authorities.

You need to ask the Regie for permission to sublet and once you have the right sub-tenant, you need to write to the Regie again. Both sample letters can be found here:

http://www.ums.ch/infos-offreur/contrat-sous-location-modeles-check-liste/