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We're in the thick of tax season, but there are still opportunities for procrastinators to save a few bucks. The clock is ticking down to April 15, the deadline by which most filers must turn in their 2018 tax returns. It's been a remarkable season so far. It's the first time taxpayers will submit returns under the new Tax Cuts and Jobs Act, the legislative overhaul that increased the standard deduction to $12,000 for singles and $24,000 for married joint filers, eliminated personal exemptions and curbed certain itemized deductions. Further, the average refund is down compared to last year. Eligible filers received an average tax refund of $2,640, down 16.7 percent from the year-ago period, according to the IRS. If you're waiting to file, here's an incentive to get started: You still have a window to save on your 2018 taxes. Here are three last-minute opportunities to consider — and one that can get you ahead for next year.

Breaks for 2018 taxes

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Individual retirement account: Consider making a contribution to your IRA of up to $5,500 ($6,500 if you're over age 50) and grabbing a deduction on your 2018 taxes, provided you fall within certain income requirements. Single filers with a modified adjusted gross income of up to $120,000 ($189,000 if married and filing jointly) can make a fully-deductible contribution to their IRA and have it count for 2018. Beyond those thresholds, filers who have an MAGI of up to $135,000, if single, or $199,000, if married and filing jointly, can take a deduction on a portion of their contribution.

"Just make sure that you tell your plan administrator that this is a 2018 contribution," said Lisa Greene-Lewis, CPA with TurboTax. "Make sure it applies to the year you want it to apply to." Don't forget you might also be eligible for the saver's credit for making eligible contributions to your IRA or your retirement plan at work. The maximum amount of the credit is $2,000 ($4,000 if filing jointly), and what you get will vary based on your adjusted gross income. Health savings account: If you're eligible, you can make a tax-deductible contribution to your HSA by April 15 and have it count for 2018. HSAs, which work alongside high-deductible insurance plans, have three tax benefits: The contributions are either pretax or tax deductible, your savings grow on a tax-free basis and you can take tax-free withdrawals for qualified medical expenses.

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You can save up to $6,900 in this account for 2018 if you have a family insurance plan, or $3,450 if you have self-only coverage. Account holders who are 55 and older can kick in an extra $1,000. Be aware that you can carry your HSA balance from one year to the next, so consider saving the money for the long-term. "Once you cross a certain threshold, you can invest your money, like you would a 401(k), and you could have years of growth from compounding," said Sharif Muhammad, CPA and certified financial planner at Unlimited Financial Services in Somerset, N.J. Entrepreneurs, save in a SEP IRA: Do you run your own business? Consider opening a SEP IRA. Though the contribution limit for the SEP is $55,000 for 2018, the amount you can deduct for the contribution will vary based on your net earnings. You have up until October 15 of this year to contribute and have it count for 2018. "With the SEP, even if you opened it up after the calendar year-end, you have until the tax extension deadline to make the contribution in case you had difficulty of getting the funds together," said Thomas O'Shaughnessy, senior director of Marcum Financial Services

Prepare for next year

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