Getting a windfall income is a great way to stabilize your finances and lay a strong foundation for savings and retirement. But depending on the source, the United States government may want its share.

Understand Tax Implications

Before you start to worry, research the tax rules for your specific income source. If the income comes from something like a lottery or employer, you have to pay full income taxes at your tax bracket level on the income. Other sources have different rules.

If your income comes from investment gains, you will have to pay capital-gains tax. Capital-gains taxes changed with the Affordable Care Act’s implementation. If your regular income puts you in the 10%-15% brackets, you do not have to pay any capital-gains tax. If your income is in the 25%-35% tax brackets, you pay 15%. If you are in the 39.6% bracket, your capital-gains tax rate is 20%.

If your income came from an inheritance, you don't have to pay taxes on the first $5.43 million inherited as of 2015. For income above that level, the maximum tax rate is 40%. (For continued reading, see Estate Planning: Estate Taxation.)

Fund an IRA

The first place to look to lower your taxes is in your retirement accounts. Contributions to a traditional individual retirement account, or a 401(k) plan, are tax deductible. That means you don't pay any taxes on the dollars you contribute to the IRA.

The maximum you can contribute to an IRA in 2015 is $5,500, or $6,500 if you are 50 years old or older. If your income places you in the 25% tax bracket, maximizing your IRA contribution will lower your taxes by $1,375.

Income limits apply to IRA contributions, and you do pay income taxes on withdrawals in the future. Those withdrawals, however, will be made at a time when you likely have a lower income, and so your total taxes paid will be lower.

Fund an HSA

If you have a high-deductible health plan, you likely qualify for an HSA, or health savings account. A health savings account works similarly to an IRA, but the funds can be used only for qualified medical expenses such as doctor appointments, hospital visits, prescription medications and doctor-ordered lab tests.

With an HSA, your contributions are tax deductible, and you pay no taxes on withdrawals. You keep your HSA funds for life, and so some savvy savers use the account as a supplemental retirement account.

If you are single, the 2015 annual contribution limit is $3,350. For families, the limit is $6,650. In 2016, the individual limit is the same, and the family limit is increasing by $100 to $6,750. Adults 55 and older can contribute an additional $1,000 per year.

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How To Reduce Taxes On ETF Gains

Sell Sluggish Stocks

If you have underperforming stocks in your portfolio, you can sell stocks at a loss to lower your capital gains for the year. Capital losses offset capital gains, but cannot be used to lower your taxes beyond that amount. Any additional capital loss is carried over to the next year.

Always think carefully before selling a stock. It is better to pay capital-gains taxes and make money than it is to lose money. Don't sell just to avoid taxes. But if you were going to sell anyway, you can try to time your sale in a tax year that will be most beneficial.

Research Additional Deductions and Credits

There are dozens of tax deductions and tax credits available that many Americans don't take advantage of. While you already likely know about tax credits for parents, there are additional education-related deductions and credits available. Those are available for both children and classes at an accredited college or university that you are taking yourself.

If you incurred high health-care expenses in a single calendar year, you may be able to write those costs off as well. To take advantage of health-care tax deductions, your spending on health care must meet certain minimums and criteria that vary based on your income.

The Bottom Line

Taxes are something we cannot escape, but good planning and understanding can help you keep your tax bill as low as possible. Do research ahead of time so that you don't have to scramble at the end of the year or in the weeks leading up to tax day.