You have until October 17, 2011 (because October 15, 2011, is a Saturday), to re-characterize your 2010 rollover or conversion to a Roth IRA if you file your 2010 tax return on time, including any extensions, and regardless of whether you requested an extension to file your 2010 tax return.

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In addition to casualty loss relief, other help may be available for victims of disasters, including extensions of time to file and make payments.

FORBES: Taxes From A To Z (2013): D Is For Disaster Relief

And you need to have the substantiation letter from the charity on or before the earlier of the date you file your return or the due date (including extensions) for filing the return.

FORBES: Tax Court Loss For Ferret Rescuer

Contemporaneous means that you have to have received it by the earlier of the date you file your return or the due date for the return, including extensions.

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Servicemen and women rank E-1 to E-5 can now file their taxes for FREE through the end of tax year 2012 (that means including extensions, so through October 15, 2013).

FORBES: TurboTax Offers Free Tax Software For Junior Military, Discounts for Officers

You can amend past returns and file for back refunds for up to three years from the original due date of a return, including extensions.

FORBES: Windfall