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When to look beyond your workplace retirement plan

Given the chance to save at work for retirement or to save on your own, the right answer might be "both."

Almost three-quarters of workers have access to either an employee-funded or company-funded retirement plan, such as a 401(k) or pension—and of those, 80 percent are participating, according to an August report from the Transamerica Center for Retirement Studies. But 58 percent of workers also say they are saving for retirement outside of work, with an IRA, brokerage account or other vehicle. Among the groups most likely to have an outside retirement savings vehicle: college-educated boomers, full-time workers, married individuals and savers earning at least $50,000.

The online survey was conducted in February and March among a nationally representative sample of 4,550 workers.

If you have access to a workplace plan, advisors say, there's good reason to focus on funding that first. "Your 401(k) is the most powerful retirement tool that you have," said Elizabeth Scheiderer, a certified financial planner with NCA Financial Planners in Cleveland.

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It's a powerful combination: pretax contributions that lower your taxable income, a high annual employee contribution limit of $18,000 in 2015 ($24,000 if you're 50 or older), and, often, matching employer funds. "It's a good problem to have if you're maxing out your 401(k)," said Scheiderer.

Even if you're not, once you've socked away enough to snag the full match, there are several reasons it may be smart to explore other savings avenues for retirement.

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Alan Graf | Getty Images

Tax diversity

The disadvantage of pretax retirement contributions: "On the back end when the money comes out, there's a big tax haircut," said certified financial planner Carina Diamond, managing director of SS&G Wealth Management in Akron, Ohio. Saving in different vehicles helps diversify the tax impact—with a Roth IRA, for example, withdrawals in retirement are tax free, while sales of brokerage account investments would be subject to capital gains taxes. "It gives you a lot more flexibility when you're retired to manage your tax bracket," she said.

Younger and lower-income workers who qualify for a Roth IRA may particularly benefit from diverting contributions there, she said, since the delayed tax benefit is more valuable. But everyone should check to see if your employer offers a Roth 401(k) option. "It can actually be better than a Roth IRA," said Diamond—there are no income caps to qualify, and the higher annual 401(k) contribution limit applies.

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Short-term goals

It's not unusual to see workers taking 401(k) loans to fund short- or intermediate-term goals: Seven percent said they have borrowed to pay for a home purchase, according to the Transamerica Center for Retirement Studies survey, while 11 percent have done so to buy a car and 2 percent to pay college tuition.

If you have such a goal on your list, once you've met that employer match, think about putting extra disposable income into a nonretirement account instead, said certified financial planner Evelyn Zohlen, president of Inspired Financial in Huntington Beach, California. That's a much better option than a 401(k) loan or withdrawal, she said—there's no risk of early-access penalties, and you aren't sacrificing growth opportunity in those retirement savings.

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Better investment options

High fees? Skimpy investment options? Employers have been doing better on both fronts, said Zohlen, but "there are still examples of egregious, expensive options." If that's the case, it's time to look elsewhere. (To assess how your company plan stacks up, check ratings at BrightScope.com.)

Even if the investment options score high marks, outside retirement sources can help fill in overall portfolio gaps. "You want to make sure you're diversified and you're investing within your own risk tolerance," said Diamond.