Assuming you are paying the standard rate of £190, paying six months in a single payment equates to £209 for the whole year or £17.41 per month, as opposed to £15.83 for 12 months and then cancelling. However, you can pay a six month payment by direct debit for £99.75, which works out at £16.63 a month. We would suggest choosing one of the six month payment options, as this means a smaller initial outlay as well as not having to wait for a refund of six month's tax.