People need all the help they can get financially. When it comes to saving for retirement, a lot of people are behind where they need to be in order to afford what they want to do with their free time after the end of their careers.

To catch up, you need to make the most of the opportunities you have. One way to save for retirement is to use Roth IRAs, and many people have turned these retirement savings vehicles into wealth-making machines that give them tax-free growth and withdrawals after they quit their jobs. Now more than ever, Roth IRAs can have a dramatic impact on your financial success, but it's essential to know how they work and what you need to do to take full advantage of them.

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Can I open a Roth IRA?

To open a Roth IRA, you need to meet two requirements. You need to have earned income from a job or from self-employment. You also need to meet the adjusted gross income limits that prevent high-income earners from contributing to Roths. You'll find those limits for 2018 Roth IRAs below:

For this filing status

Contributions are reduced if income is above this amount

Contributions are not available if income exceeds this amount

Single, head of household, or married filing separately IF you didn't live with your spouse during the year

$120,000

$135,000

Married filing jointly or qualifying widow or widower

$189,000

$199,000

Married filing separately IF you lived with your spouse at any point during the year

$0

$10,000

Data source: IRS.

If your income is below the levels in the first column above, then you'll be allowed to contribute $5,500 to a Roth IRA in 2018 if you're younger than age 50, or $6,500 if you're 50 or older. Pro-rata reductions apply if your income falls in between the two numbers above. For example, joint filers with incomes of $198,000 would only be able to make Roth contributions of one-tenth of the limits, or $550 for those under 50 or $650 for those 50 or older.

You can open a 2018 Roth IRA right now. But you also have until mid-April 2019 to do so, because IRAs give you the ability to get an extended deadline before making contributions for a given tax year.

What other ways can I get money into a Roth?

If you don't meet the income limits for contributions, there's another way to move money into a Roth IRA. That involves taking money that's in traditional retirement accounts, including regular IRAs and 401(k) plans, and doing what's called a Roth conversion.

Roth conversions have pros and cons. On the downside, you have to pay taxes when you convert money in a regular IRA or 401(k) to a Roth. However, from then on, the money is treated the same way as a Roth contribution, giving you tax-free treatment for portfolio income and gains on your investments. The reason converting to a Roth is particularly advantageous right now is that with income tax rates having fallen as a result of tax reform, the tax hit you'll take from converting is less now than it has been in years.

Why it makes sense to have a Roth

Some people wonder why they really need a Roth IRA, especially if they already have another type of retirement account. Yet once you actually retire, there are several financial planning advantages of having a Roth at your disposal.

The biggest reason to consider a Roth is that it'll give you a tax-free source of money for retirement spending. Those who rely solely on traditional IRAs and 401(k)s often find that their tax bills are a lot higher than the expected, because they end up having to pay taxes on their distributions. Having a Roth at your disposal can let you control your tax bill, avoiding moving into too high of a tax bracket and also potentially working around some traps that can plague retirees whose taxable incomes are too large.

The worst thing a successful investor has to do is to give up hard-earned wealth to the IRS. The special treatment that Roth IRAs get avoids that outcome, letting you keep more of your money and ensuring you'll have the flexibility you need throughout your retired years.

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