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You've been saving for your child's higher education for a long time, and now it's time to start using it to pay for college costs. We all learn by doing, but when it comes to tax-advantaged savings such as a 529 College Savings Plan (where the IRS is looking over your shoulder), it's best not to make any rookie mistakes.

Keep these four tips in mind as you make your freshman withdrawals from your 529 savings account.

1. Take out money for "qualified education expenses" only

Eligible expenses at colleges, universities, and other post-secondary institutions include tuition, books and supplies, room and board, and special equipment required by the school or class (such as an easel for art students). Computers (including tablets) and peripherals such as printers and education software are also covered. Some expenses that aren't covered include travel expenses to and from campus, campus logo items such as hats or sweatshirts, and computer games, among other things. In general, it's best to stick the expenses outlined by the IRS.

2. Tell your college student to save receipts and billing statements

You need to show the IRS that withdrawals from your 529 plan did indeed go toward eligible educational expenses. That means showing documentation in the form of receipts, canceled, checks and other forms of payment. Privacy rules often do not allow parents to view bills and expenses from the university—and the fact is, many purchases such as textbooks and other education and living costs will likely be made by your child, who may be a long way from home. Have this "documentation discussion" sooner rather than later with the recipient of 529 funds. After all, it will be you, the owner of your 529 plan, who is responsible for any tax reporting and potential liability if your withdrawals exceed qualified expenses or you cannot substantiate those expenses.

3. Don't make a tuition payment mistake

Any qualified expenses you incur must align with withdrawals from a 529 account in the same tax year. If you withdraw 529 plan money in December for tuition the next semester—and don't pay the actual bill until January (a new tax year)—you may find that you've exceeded your withdrawals for this year, and perhaps not left yourself enough money to pay for qualified expenses the next year. If you take out money to pay for next year's tuition in the current year, make sure it is paid to and logged by the school's bursar office before the new calendar year.

4. You can still make contributions and change investment allocations

Just because you start withdrawing money from a 529 college savings plan doesn't mean you should necessarily stop contributing to the plan. And by all means, continue to closely monitor your investments. Many parents find that they can save for college while their child is going to college, and your existing 529 plan could still be one of the better ways to do so. But keep the shorter time horizon top of mind. Hopefully by now, as your child has gotten older, the asset allocation has become more conservative. (The IRS allows you to change your investment options twice every calendar year in a college savings plan and when there is a change in designated beneficiary.) Now is a good time to evaluate whether your college nest egg is allocated in such a way to allow you to meet the primary goal of your 529 plan—namely, to pay for higher education.

These tips should help you do as effective a job of paying for higher education as you have done saving for it.

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