Here's one good reason for the happily married to rejoice: They have better access to a tax-friendly retirement savings strategy.

Generally, a Roth individual retirement account allows savers to put away up to $5,500 (plus $1,000 if you're age 50 or older), have the money grow free of taxes and then tap it in retirement on a tax-free basis.

As useful as these accounts may be, not everyone will have access to them. Taxpayers whose modified adjusted gross income exceeds $120,000 if single or $189,000 if married won't be able to make the full contribution directly to a Roth IRA.

That's where Roth conversions come in: You take a chunk of traditional IRA dollars, pay income taxes and convert it to a Roth IRA. Income limits do not apply to conversions.

Be aware that This move is a permanent one.

The Tax Cuts and Jobs Act put an end to "recharacterizations," or the unwinding of Roth conversions that were completed after the end of 2017. If you made a Roth conversion last year and you'd like to undo it, you have until Oct. 15 to do so.

Married couples weighing a Roth conversion have an added sweetener, according to Robert S. Keebler, CPA and partner with Keebler & Associates.

He spoke at the Financial Planning Association's annual conference in Chicago on Monday.

"The income tax brackets are more favorable for married people, so convert while both spouses are alive," he said.

Here's why a Roth conversion might be a great deal for couples.