A spousal IRA lets you put away retirement funds on behalf of a spouse, even if they have little to no earned income. But you must have wages or earned income in order to make that investment.
Other restrictions apply, depending on whether you are investing in a traditional or Roth IRA.
If you plan to fund a spousal IRA for 2018, the same April 15 deadline applies.
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A back-door Roth IRA lets you put funds in a traditional IRA and eventually convert that money to a post-tax Roth.
This strategy is helpful for individuals whose income is too high to contribute directly to a Roth IRA.
The funds can be converted to a Roth at any time. But in order to get the back-door Roth process started, you must make the contributions to a traditional IRA by April 15, Slott said.
Residents of two states — Maine and Massachusetts — have until April 17 to file their federal taxes this year. Those states observe Patriots' Day on April 15 and Washington, D.C., celebrates Emancipation Day on April 16. Holidays in the nation's capital affect tax deadlines in the same way as federal holidays, according to the IRS.