Tax underpayment notification

hardy1973

I received a rather unwanted letter from HMRC stating that I owe them £1624 in backdated taxes for 2010/2011. Apparently the figures sent in on my P11D by my employer (for company car and fuel) had not been transposed into the correct tax code. I've checked all backdated P11D forms to 2007 and they are all correct so I don't understand how they haven't picked it up for the last tax year when it's been correct in previous years.
My tax code was modified to K66 as a result 4 weeks ago. Then at the weekend I got another tax code change (to 308L) which now doesn't take into account the taxable benefit of my fuel card. I've notified them of the change but can't understand how they manage to get things so wrong from 1 piece of information.
I've read a number of threads regarding underpayments of tax, where you pay and where you don't etc. Can anyone let me know where I stand on this issue? I don't want to waste my time stressing out with the tax office if the end result is I have to pay the tax back BUT if it's the fault of HMRC do I have any recourse with them?

John_Pierpoint

It is perfectly reasonable that HMRC has only just identified a tax mistake in 2010/11.
I haven't even sent in my figures yet.

Do you understand how your tax liability for 10/11 is calculated?

hardy1973

I contacted the tax offoce and they broke it down for me. i was just confused that for 1 year they decided not to take the associated tax for my company vehicle when in all preceding years they took the correct amount. All P11d's add up so i don't understand what changed at their end when all of the information they were given was correct. I didn't notice the increased differential in pay as it coincided with the cancellation of my final salary pension and a pay rise!

chrismac1

This sort of muck-up isn't all that unusual, hardy. However, it could be worth posting your 10-11 P60 figures, and all relevant other information. I've seen some real howler calculations in my own client base, such as counting something twice and then trying to tax the client twice. Schoolboy errors are not a rare beast in HMRC.

hardy1973

Thanks Chris. I'm currently working my way through all P11d's to make sure the BIK figures are correct before I go back and ask the tax office to explain how they have managed to do what they have. Already had 2 new tax codes this year and neithere are correct!!!!!