Open an IRA and make a contribution for the previous year until April 15 of the succeeding year.

You may open an IRA and make a contribution for the previous year until April 15 of the succeeding year. If you are eligible for a deductible IRA, this is one of the very few steps that you can take after year-end to reduce your taxes from the previous year. Note that filing an extension on your tax return does not extend the April 15 deadline for making IRA contributions.