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We get it. People with millions of dollars sometimes like to hide the money overseas. Naturally, the government frowns on tax evasion. Following the financial crisis, Congress in 2010 enacted the Foreign Account Tax Compliance Act, also known as FATCA. FATCA works through "dual reporting": Other countries agree to report on the assets held by U.S. account holders. These account holders, in turn, must report to the IRS that they have money in foreign bank accounts each year when they file their taxes, says Katelynn Minott, a CPA and expatriate tax specialist with Bright!Tax.

Some people are unhappy with the requirements. Edd Staton, an expat retiree who lives in Ecuador, said FATCA was intended to reel in "big-league tax evaders stashing money offshore."

Small oversight leads to big problem

Problem is, according to Ed Slott, CPA and founder of Ed Slott and Co., "they cast such a wide net … they catch the little fish — people who weren't doing anything wrong." A client of Slott's was caught up in an IRS audit and faced stiff penalties about a year ago after having neglected a small but crucial part of his tax return. Slott says the client hadn't told his accountant he had a bank account with about $3,500 in a foreign country. As Slott explains, Schedule B asks you to disclose whether you have a bank account in a foreign country. "Almost every tax program defaults to 'No,' " Slott said. More from Personal Finance:

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Five things single parents absolutely have to pin down You must tell the government that you have this account, no matter how small, Slott says. "There's nothing wrong with having the account," he said. "It's not disclosing it" that can cause problems. And it did cause problems for Slott's client. The penalties were massive, and the issue was solved only with the intervention of an attorney experienced in the tax situations of people who live out of the country.

Who has to file?

How much you earn in income and how much you hold in assets help determine your filing requirements. Americans living abroad must still file a U.S. tax return, says Minott. "It doesn't matter where you live, if you pay foreign taxes or if the U.S. has a tax treaty with their country of residency," she said. As well as your Form 1040, there are often additional forms — for the foreign earned income exclusion, or the foreign tax credit form. If you receive only Social Security and have no other income anywhere in the world, it's possible you do not require a tax return, regardless of where you live, according to Minott.

Minott says that if you are a single taxpayer who lives in, say, New Jersey and has a U.K. bank account worth more than $50,000, "you must file Form 8938 and the FBAR disclosure" for foreign bank and financial accounts. It pays to be scrupulous in your tax reporting and requirements. As Staton points out, if "you can't afford to live in the U.S. because of the high cost of health care, taxes, among other costs," the last thing you want is to then incur penalties from the IRS. Staton, the author of three books on retiring overseas, is dedicated to making this idea a part of the national conversation. "Choosing this path for many baby boomers may be the best or only viable option to rescue their retirement," he said.

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