The Internal Revenue Services offices in Washington, D.C.
If you're holding a bank account or an investment account overseas, you're running out of time to come clean to the IRS.
The Internal Revenue Service will shut down its voluntary disclosure program on Sept. 28, meaning those who have failed to participate could be subject to large fines, penalties and criminal prosecution.
Since the program's launch in 2009, more than 56,000 taxpayers have stepped up to report their foreign financial assets. In all, they paid $11.1 billion in back taxes, interest and penalties since then, according to the IRS.
"The offshore voluntary disclosure program is coming to an end," said Katelynn Minott, a CPA with Bright!Tax. "There are a number of different ways to get compliant."
Here's what you need to know.
Accounts overseas
Though there are legitimate reasons to hold accounts overseas, Americans with these assets must report them to the IRS and Treasury.
Frustration over those requirements — and the related cost of remaining in compliance — has led some citizens abroad to renounce their citizenship.
Play Video IRS ending amnesty for taxpayers with secret foreign bank accounts 
"One thing that comes up with a lot of clients is that they have a big transaction — such as buying a house — and the bank is loaning them $500,000," said Minott.
"This transaction hits their account before they pay, and that gets disclosed," she said. "It unsettles people." In that case, this person wouldn't have to pay taxes on the money, but the IRS still needs to know about it.
Treasury requirements
If you have a foreign account, you have until April 15 to file a Report of Foreign Bank and Financial Accounts, or FBAR, with the Treasury's Financial Crimes Enforcement Network.
If you fail to file on that deadline, you get an automatic extension to Oct. 15.
You must submit an FBAR if you had interest in or signature authority over at least one account outside of the U.S., and the aggregate value of all the foreign accounts exceeded $10,000 at any time in the year.
Failure to turn in this form could put you on the hook for a penalty as high as $10,000.
If you knowingly flout the reporting requirement, you may be charged a penalty of $100,000 or 50 percent of the balance in the account. In the most extreme cases, you could face criminal penalties.
IRS requirements Play Video Lying about your taxes? You could face up to five years in prison 
If you're required to submit an FBAR, you may also need to turn in Form 8938 — a statement of specified foreign financial assets — to the IRS.
Single taxpayers who reside overseas are required to file Form 8938 if the total value of their foreign financial assets exceeds $200,000 on the last day of the tax year ($400,000 for spouses filing jointly) or if it exceeds $300,000 at any time in the year ($600,000 for spouses filing jointly).
Single filers who reside in the U.S. must submit Form 8938 if the total value of their foreign financial assets exceeds $50,000 on the last day of the tax year ($100,000 for joint filers) or if the value exceeds $75,000 at any time during the year ($150,000 for couples filing jointly).
If you fail to disclose these amounts, you could face a penalty of up to $10,000.
If you continue to withhold the information even after the IRS notifies you of a failure to disclose, you may face a maximum penalty of $60,000, along with potential criminal penalties.
Reporting relief
The offshore voluntary disclosure program is only one way to get compliant with the IRS, said Minnott.
For now, filers can also use the streamlined filing compliance procedures to get up to date if they haven't been aware of their filing obligations. About 65,000 taxpayers have become compliant through this program, according to the IRS.
"This is still a way for people to get caught up if they've just found out," said Minnott.
The IRS has said it will continue to offer the streamlined program, but has also warned that it may end it at some point.
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