Form 4868 - Further Extention

Please help!  I'm an idiot and leaving it 'til last minute, but I'm just confused when it comes to "Estimated Tax Liability" and "Total 2006 Payments".     Is it just the amount of tax taken out of my wages and NI contributions or what?  I'm filing separately from the UK, I know I need to convert to dollars, its just sticking me on this as I need to get it done.  (I qualify for foreign earned income exclusion if that helps.

Thank you for any help!
Christine

Total 2006 payments = total 2006 payments TO THE US GOVERNMENT.  So your UK PAYE and NI is ignored.  If you've been in the UK all year, it's not likely you've paid anything.  If you moved this year, then copy the info from your 2006 US W2.

Estimated Tax Liability = how much you think you owe the US.  Most overseas filers owe very little.  If you're not sure, pay a few hundred - you'll get a refund if you overpay.