She uses aftertax salary--no big sacrifice, given her low bracket--to fund a Roth individual retirement account.

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But he now had extra income from moonlighting and wondered whether he should use it to fund a tax-deductible SEP-IRA (a special individual retirement account for the self-employed), or should pour his extra savings into the 529s.

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If trimming spending doesn't get you to that magic number, consider temporarily cutting back on contributions to your individual retirement account or 401(k) and using that money to bolster your emergency fund, says Mr. Weingarten.

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You can fund an HSA account even if you contribute to a 401(k) or other retirement plan and even if your income is too high to fund a deductible IRA. Unlike some retirement plans for small businesses and the self-employed, an HSA can be funded (and deducted from other income) even if you do not show a profit from your business.

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