You can either advise the various utility companies of the new tenant or leave it up to them to make contact themselves. However, if you were previously living at the property, then it's probably sensible to contact the companies yourself, to let them know you no longer live there and give them the name of the new occupant.
If your new tenant moves out at some point, check all utilities are paid up to date, before returning their deposit, otherwise, you will have Bailiffs visiting alot. If bills are not paid up to date, then those costs can be deducted from the deposit.
Also, you should really inform your mortgage provider that you are renting the property out and also your insurers. If you don't let them know, then it could cause problems in the future. However, many people rent their properties for years, without informing anyone.