You can request a Returns Bag @Filipe Nobrega - by posting your request on this thread - although, if the router is not of significantly recent manufacture, you may well be advised to simply recycle it.
I have just cancelled my broadband only service after the end of an 18-month contract. I was advised that I would need to return the equipment. I dont' understand why everyone else seems to be allowed to keep their routers while I have to return mine. PLease advise.
There is no requirement to return the router after disconnection. We send a returns bag in case you are not going to use it, as your new provider will probably send you their own one.