College 529 plans can help meet expenses during a student’s postsecondary years, but they don’t have to cover all costs to help families’ financial situations.

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That’s one of the findings in a report by 529 plan administrator Ascensus College Savings, which administers more than 3.5 million 529 plan accounts, representing more than 27 percent of the total 529 accounts administered across the nation. The company provides services for 31 plans across 17 states and ranks first among 529 plan managers.

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Ascensus also reported that 529s are predominantly used to save steadily during a beneficiary’s childhood.

The average balance across all accounts, it said, was $20,070, suggesting that families are using 529 plans to build a foundation to partially fund postsecondary education, even if they aren’t counting on those accounts to pay for the whole expense.

More than 75 percent of the contributions to 529s during 2015 were $200 or less, 61 percent of accounts had annual contributions of $2,000 or less and almost 77 percent of accounts had contributions of $4,000 or less. Fewer than 4 percent of accounts had total annual contributions of $14,000 or more—indicating that most families “are saving modestly and progressively over time rather than in larger lump sums.”

In 2012, more than $21 million in Ugift contributions were made to Ascensus College Savings 529 accounts. In 2015, this amount increased by 299 percent to over $87 million in Ugift contributions.

In addition, it found that strategic and modest withdrawals throughout a student’s education appears to be lessening reliance on loans. Seventy percent of withdrawals from 529 accounts that account owners identified as qualified were for $5,000 or less.

That reduced reliance on loans could have major implications for retirement planning if it allows students—or their parents—to be less in debt once college days have ended, since student loans have an impact not just on the graduate but also on parents who may have taken on debt to help out with tuition.