Is there anything to stop me putting all my figures in for the last calendar year as soon as the HMRC lets me and getting a figure so I can pay off gradually over 12 months? \n\nThis year I had to do my first return for a property rental. But only 2 months fell in 14-15 so it was easy. I've all my paperwork in spreadsheets / ring binder. \n\nIs there any reason NOT to do this?