Americans working abroad face unexpected financial issues

Accepting a job abroad can be exhilarating and scary at the same time.

However, in the midst of the excitement and frenzied preparation, don't forget to plan for your personal finances as an expatriate. Topping the list of important considerations is taxes.

Western businessman in Dubai
FMB Photo | Getty Images

"As long as you are a U.S. citizen, you are responsible for paying U.S. taxes no matter where you are in the world," said Dan Leonard, a certified financial planner with Rice Pontes Capital.

The American expat population is not formally tracked, but some estimates peg it at roughly 7 million in more than 100 countries. And while not all of those expats are earning income, those who are must adhere to tax laws in both their host country and the States.

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In fact, the U.S. is the only developed country that requires its citizens to pay income taxes even when they live overseas.

And while there are tax treaties with many countries that can reduce or eliminate your tax burden, failing to file an annual return will incur interest charges and late-payment penalties. Also, check with your state to see if it requires you to file a return. Some do, some don't.

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It's also worthwhile seeing if any of the tax treaty's particulars pertain to any of your financial interests.

"Before you leave, make sure you know the [U.S.] tax treaty with that country," Leonard said. "Knowing what's covered by it is important."

For instance, if you own a 529 college savings plan, its gains could be taxed in your host country. Or, similarly, if you establish a tax-qualified account in another country—such as a retirement account that is tax-deferred—and then return to the States, the account might get different tax treatment from Uncle Sam.

For a 529 plan, if your host country treats gains in the account as taxable, consider transferring ownership of the account to a trusted U.S.-based family member if your plan allows it.

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For all your financial accounts—whether brokerage, retirement or regular savings—make sure the institutions that hold them will allow you to keep your money there when you move abroad.

"Some firms won't allow accounts held by nonresidents," Leonard said. "If they see it's not a U.S. account, they don't want it."

This is because regulations governing cross-border investments have become more stringent, and some firms have chosen to avoid the added reporting requirements by simply refusing to hold non-U.S-based accounts. Even if your firm will keep you as a customer, some of its service and product offerings might be limited.

Also, it's important to know that you won't be able to walk into any financial institution in your host country and assume you're wanted as a customer. Due to U.S.-imposed reporting requirements for all accounts owned by U.S. citizens, some firms, like their American brethren, have simply stopped serving expats.

Muharrem Oner | Getty Images

Additionally, once you move away from American soil, you no longer can purchase shares in U.S. registered mutual funds.

"You can buy stocks and bonds, but you cannot buy mutual funds if you live [abroad]," Leonard said.

Another important pre-move task is to make sure you have any documents needed to open a bank account in your host country. Some countries require little more than proof of address and a couple forms of identification, while others ask for much more, such as proof of income or a letter from your employer.

If you do open any financial accounts in your host country, the Internal Revenue Service will require—with very few exceptions—annual, detailed information about your accounts if their aggregate value exceeded $10,000 at any point during the tax year.

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As far as starting investment accounts in your host country, financial advisor Marcio Silveira advises against having a home-country bias in your investment choices. In other words, you might end up overexposed to that country's industries.

"Some people who move to a new country end up taking too much risk because their view is narrow," said Silveira, CFP and founder of Pavlov Financial Planning. "Just because you live there doesn't mean you should have too much invested there."

Also, if you want to establish credit in your host country, be aware that you are starting fresh.

"You will have no credit history," Leonard said. "It's essentially like you're 19 and want a credit card. They take you as the risk that you are."

"Pay all your bills. Keep your U.S. credit good. Make small charges, and pay them to keep a credit history." -Maura Griffin, founder and CEO of Blue Spark Capital Advisors

Even after you have established credit in a different country, you should maintain a credit history in the U.S. if you think you'll ever return.

"Pay all your bills," said CFP Maura Griffin, founder and CEO of Blue Spark Capital Advisors. "Keep your U.S. credit good.

"Make small charges, and pay them to keep a credit history," she added. Otherwise, you might struggle getting credit if you return to the U.S.

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Also, determine whether there are restrictions on anything valuable you want to bring into your destination country, whether it is a family heirloom or firearms. For instance, you might pay tax on valuables brought into a country, or you might end up relinquishing your firearms if you show up with them and they aren't permitted in the host country.

"Find out what is permissible," Leonard said. "Talking to a U.S. consulate where you're going is not a bad place to start."

—By Sarah O'Brien, special to CNBC.com