"In general, 10 years is often the key differentiator between Class A and Class C," said Mark Kantrowitz, publisher and vice president of research at Savingforcollege.com.
"If you're going to be invested for at least 10 years, the Class A is fine," he said. "Less than that? Class C is better."
In recent years, plans have also made convertible C-share classes available, wherein the fund changes to the A-share after a certain period of time.
The conversion generally takes place once the cost of the C-share over time reaches parity with the upfront cost of the A-share version of the fund, according to Leo Acheson, associate director, multiasset and alternative strategies at Morningstar.
Some fee-only advisors — financial professionals who don't collect commissions — also encourage clients to use direct-sold funds and provide general recommendations on them, Kantrowitz said.
Cost-savvy savers aren't the only ones keeping an eye on advisors' 529 share-class recommendations.
FINRA, the self-regulatory organization that oversees broker-dealers and their advisors, recently kicked off an initiative, encouraging firms to come clean about advisors inappropriate 529 share class recommendations.
"It's important to understand what plans the advisor or broker is able to recommend to you," said Gerri Walsh, senior vice president of investor education at FINRA.
"You will want to ask what the costs are so that you can make informed choices about which plans fit your budget and work best for your circumstances," she said.
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