Rich - I'm allowed to overpay up to as much as £500 a month with no interest, so I reckon that if I can save £100 a week, that's about £433 a month, so I should be fine. I'm sure some weeks/months I won't be able to do it, but if I can average about £5k a year in overpayment, then I might be able to half the ammount of time to pay the mortgage back. So instead of 30yrs, I could pay it back in say, 15yrs.