I'm sorry but I don't understand what you mean by an 11 month service? What happens in this 12th month? No street lights, no refuse collection, no police, no emergency services, libraries shut etc etc etc. You get 12 month service from April to end of March the following year when you get your new bill. I suggest you go to the council in person and speak to someone face to face in the council tax department who I am sure will explain it all to you as I cannot explain it any better than I have already. TLC has explained it in his last posting and tables very well. In your second post, I see you have counted April 2010. I think it should have read Apr 09 (free) May, June, July, August, Sept, Oct, Nov, Dec 09, Jan, Feb, 2010 all paid and March 2010 free. That is 10 payments but I see you have included Apr 2010 on this list when it should not be. The payment in Apr 2010 is your first payment of the new year. I'm sorry I cannot think of any other way to express myself, so I will leave it to others to try and help you.