Budget for 40% of the historical interest remitted. Historical interest is the interest from the date of your arrival in the UK to the date you closed the account. If you end up in the 22% bracket, you'll have a nice spot of change left over. If you budget for 22% and end up in the 40%, you'll be forced to refinance just to get the money to pay the tax. So that's why Guya's recommending budgeting for 40%.
Even better, you may be able to "cease source" your account before the year's end (5 April 2008), and pay no tax at all upon remittance. Check with a UK tax professional as to whether or not your account could benefit from the cease sourcing rules. You have just days to co-ordinate this. And no, before you ask, I won't answer any further questions on an open forum regarding the cease sourcing rules. Each case is individual and requires a full consultation to determine eligibility.
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