When starting a new mobile contract it's best to block all Direct bills to mobile, Premium bar and International Bar to start, you can always remove the bars later by calling customer service. On new contract or upgrade from 1 October 2018 you can now set a spend limit between £0 - £100 to protect you from unexpected bills as you can always change this in My Vodafone or by calling customer service. Most people on this form don't quite understand what a contract means. You are agreeing to pay them a monthly charge for 1 or 2 years plus any extras charges which you must pay on time. If you cannot guarantee you can afford it for the year(s) don't sign up use pay as you go no excuses please. Look after your phone and insure it, 2 years is a long time paying for something you have broken or had it stolen. I have used Vodafone, O2 (Cellnet), EE (T-Mobile & Orange), Three, Virgin and Tesco for over 26 years and I find now it's easier to buy my phone outright and look for the SIM only deals. It's so easy to change network with a PAC code and your number changes over the next working day and automatically cancels your existing contract.