Whether you're new to the world of retirement savings or have been contributing to a plan for years, if you're not putting money into a Roth, you could be making a huge mistake. Roth IRAs offer a world of benefits that other retirement plans simply can't match. Here are three in particular you should know about.

1. You can lock in your present tax rate

Maybe you're not happy with the extent to which your earnings currently get taxed, and feel you're paying the IRS too much. But be that as it may, there's something to be said about the evil you know versus the evil you can only anticipate. When you save for retirement with a Roth IRA, you pay taxes on the money you put in, but your withdrawals are taken tax-free down the line. Not only will you never have to pay taxes on that money if you go this route, but you won't have to worry whether tax rates in general will go up over time.

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Furthermore, if you have reason to believe your income will actually go up in retirement (say, you're saving aggressively, and own a family business you plan to maintain for as long as you can), it definitely pays to get those taxes out of the way now, while you're used to paying them. This way, you'll avoid surprises later in life, and have more flexibility as to how you might utilize your savings.

2. You can pass it along to your heirs

Though traditional IRAs offer many benefits, one major drawback is that they mandate that you withdraw a certain portion of your savings each year once you turn 70 1/2. These withdrawals are known as required minimum distributions, or RMDs, and they can be a pain for two reasons. First, RMDs trigger taxes, which means you'll lose a share of that income off the bat. Additionally, RMDs prevent seniors from stockpiling money in their retirement accounts and passing it along to their heirs.

Roth IRAs, however, work differently. Because Roth accounts don't impose RMDs, you can leave your money to sit and grow indefinitely. Not only that, but you can actually continue making contributions to your Roth IRA as long as that money comes from earned income. So while you can't transfer money from a savings account to a Roth IRA, if you're still working a few hours a week at age 80, and want to stick your earnings into a Roth, you're free to do so.

The best part? If you don't deplete your account balance by the time you pass, you can leave that money to your heirs, and then they'll get to enjoy the tax-free withdrawals you benefited from in your lifetime (assuming your account is open for at least five years before those distributions are taken).

3. You get more freedom and flexibility

Some folks shy away from saving in a traditional retirement account, be it an IRA or 401(k), because they're afraid to lock their money away for several decades or more. Since traditional retirement accounts are funded with tax-free dollars, they impose stiff penalties for withdrawing funds before reaching age 59 1/2. But that could leave you in a precarious financial situation if, say, you lose your job, deplete your emergency savings, and feel compelled to sell your home or rack up credit card when you have $300,000 sitting in a retirement fund.

On the other hand, if you open a Roth IRA, that money is yours to access at any time, and for any reason, without penalty. Because you're not getting an immediate tax break for contributing, the IRS isn't concerned with when you remove that money. The only catch is that this flexibility applies to the principal portion of your account, not your earnings. If you put $5,000 into your Roth for three years in a row, and that balance grows to $20,000 because you invest it wisely, you can withdraw the first $15,000 without a problem even if you're nowhere near 59 1/2. Touch that $5,000 in gains, however, and you'll be subject to penalties.

Of course, this particular Roth IRA benefit needs to come with a bit of a caveat. If you remove any portion of your balance during your working years, that's money you won't have available in retirement. Not only will your account be short that principal, but you'll lose out on whatever sum that withdrawal could've grown into via investments. So while it's one thing to dip into your Roth IRA because you're in a true financial bind, it's another to withdraw a chunk of cash at age 40 in order to swing a vacation.

Though Roth IRAs do come with income limits that make higher earners ineligible to contribute directly, there's always the option to go the backdoor route, which means funding a traditional IRA and then converting that account into a Roth. If you take this approach, you'll need to be prepared to pay taxes on the sum you roll over, but that's no different than if you were to open a Roth IRA in the first place. Even if you're happy with your traditional IRA, it pays to consider moving a portion of your savings over to a Roth. This way, you'll get some degree of protection from future taxes and a whole lot more flexibility with your cash.

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