Can my landlord legally withhold my deposit until I have paid the final utility bill?

I've had this problem before and managed to get my deposit back. Usually they do say that you have to pay all utilities - it should say it either in the contract or in the agreement from the deposit protection company - but if you are financial problems then they can usually be quite flexible. They could also say that you just need to inform them of how to find you, so firstly you need to contact all the companies and give them your new address so that they can track you down. Get them to send you confirmation of this in writing so you can show this to your landlord - as son as he sees that the bailiffs aren't going to be coming round to the house and that they know it's your debt and not the property's then he should be fine with it. Then you can set up a payment plan with each company so that it's all formal and it shows exactly what date you will have paid it off. When I did this it was set up to be all paid off 18 months from the date I moved out, so I sent a copy of this to my landlord with a letter saying that it was more than unreasonable that he would suggest I wait for 18 months to get my deposit back, and that the debt was now on my parent's house so there was no need for him to be involved in it or concern himself with it anymore, and was fine with it, sent my deposit back no problem. If there's still an issue you should send all this info to the deposit protection scheme (it's the law that he should have paid it into one) and they sort out disputes and act as a third party. Also ask your CAB for advice.