Were you caught off-guard when you carefully documented every expense and deduction on your tax return, only to find out that you owed the government money?

Now is the perfect time to recalculate, reassess and regroup to try and avoid any surprises the next time April 15 rolls around.

Things the average taxpayer might not think of, like self-employment income or the profit from selling personal property, are what often lead to owing taxes.

“The ones that have out of the ordinary items that cause them to owe are the ones that get caught off guard,” said Kathryn Morgan, a tax specialist and Air Force retiree in Louisiana.

Statistics from the Internal Revenue Service show that about 75 percent of taxpayers got a refund in 2014. But for the remaining 25 percent that find themselves having to pay, tax experts have several tips:

- Keep track of all “extra” income throughout the year and pay taxes as you go, if necessary. Morgan said one of the biggest reasons military members find themselves owing money is that they have a self-employed spouse who did not pay taxes on income. Payments can be submitted quarterly to the IRS.

- Unexpected tax payments may also come up in relation to selling a house or inheriting money, according to Morgan. Generally, any income throughout the year not included on your Leave and Earnings statement or pay stub could be taxable come filing time.

- The online tax-filing system Turbo Tax recommends that taxpayers check their withholding frequently to see if they are paying too little – or too much. Life changes such as marriage, divorce or having a baby all affect how much taxes should be withheld from each paycheck. The more dependents you claim, for example, the less will be withheld, and vice versa.

Some people actually use their withholding as a savings account, Morgan said, purposely claiming less exemptions and paying in too much so that they will be almost guaranteed a hefty refund. Financial advisers often recommend against this, instead advising families to put money in their own savings accounts each month where it will earn interest. They also point out that this makes each monthly paycheck smaller.

But there’s something to be said for a “surprise” refund every year.

“People need to have a realistic expectation of what they can live with,” Morgan said. “Many people use larger withholding as a forced savings account they can only tap once a year, and if they know themselves well enough to know they need that, it works.” 

Morgan said the best advice is setting clear goals for yourself when it comes to taxes and income.

“The trick to this is knowing what you want at the outset,” Morgan said. “Withholding works like a see-saw. One end is your paycheck and the other is your tax return. Some folks want that see-saw to be level, some want the tax return side to go up and some want the paycheck to go up … Unfortunately the see-saw doesn't bend in the middle.”

Need help?

- Financial advisers and tax consultants can explain your situation and help devise a year-round plan for managing your income and taxes. Many offer military discounts, too.

- The Internal Revenue Service has an extensive website detailing everything you ever wanted to know about taxes. Get started at www.irs.gov.

- The IRS has a detailed withholding calculator. http://www.irs.gov/Individuals/IRS-Withholding-Calculator

- Online banks, financial advisers and tax services also have several calculators, including this one at bankrate.com that helps estimate self- employment taxes.

http://www.bankrate.com/calculators/tax-planning/self-employed-business-tax-calculator.aspx