The IRS is firm on the April 15th deadline. Your contribution must be made by the filing deadline, which does not include extensions. Contributions made after April 15th will count as a contribution for the next year. For example, a contribution after April 15, 2009, will be a 2009 contribution. Also, when you make the contribution on or before April 15th, make sure the custodian notes that it is a contribution for the prior tax year.
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