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Real estate taxes are deducted when they are paid to taxing authority - not when the money were transferred to the escrow account.
When the mortgage company paid real estate taxes for you and created a negative balance on your escrow account - that means - they loaned you the money which were used to pay real estate taxes. When you paid back a loan is irrelevant.
You may not deduct your payment to the escrow account - you may only deduct payment made to taxing authorities
.To be deductible, the tax must be imposed on you and must have been paid during your tax year
So - on your 2011 tax return - you may deduct only the amount you paid (or paid on your behalf) to taxing authorities.
If real estate taxes were paid in previous years - and you did not deduct these payments - you may amend your past tax returns
and correct that mistake. If you are due a refund - it will be issued to you if correction is made withing three year statute of limitation.
See for reference - http://www.irs.gov/taxtopics/tc503.html
If a portion of your monthly mortgage payment goes into an escrow account, and periodically the lender pays your real estate taxes out of the account to the local government, do not deduct the amount paid into the escrow account. Only deduct the amount actually paid out of the escrow account during the year to the taxing authority.
Sorry if you expected differently.
Be sure to ask if any clarification needed.