The US extension deadline is approaching: Have you missed anything?

Key takeaways

• 15th October is more than a tax return deadline. While it is the extended filing deadline for many US expats, a range of international reporting requirements may also need to be completed before this date.
• An extension to file is not an extension to pay. Tax owed may have been due months earlier, and interest and penalties can continue to accrue even when a filing extension is in place.
• Foreign financial accounts should be reviewed carefully. US taxpayers with foreign accounts exceeding certain thresholds may need to file an FBAR, with 15th October serving as the automatic extended deadline.
• Foreign gifts, trusts and other cross-border arrangements can trigger separate reporting obligations. Missing forms such as Form 3520 can result in significant penalties, even where no tax is due.
• A final compliance review can prevent costly mistakes. Foreign accounts, gifts, trusts and investments often have additional reporting requirements that are easily overlooked but can carry substantial penalties.

For many Americans living overseas, 15th October is one of the most important dates in the US tax calendar. It is the extended deadline for filing a federal income tax return where a valid extension has been obtained. However, several international reporting obligations may also need attention before the deadline arrives.

Filing deadlines

• 15th April - Standard federal income tax filing deadline.
• 15th June - US citizens and resident aliens living abroad generally receive an automatic two-month extension to file.
• 15th October - Additional extension deadline where a valid extension request has been made.
• 15th December - In limited circumstances, taxpayers living outside the US may request a further discretionary extension.

However, this final extension is often misunderstood. Whilst additional time may be available to file Form 1040, the extension does not automatically apply to all international reporting obligations. Certain information returns, elections and cross-border filing requirements may be subject to different rules, creating unexpected compliance risks for internationally mobile individuals.

Areas to review before 15th October

With 15th October approaching, there are several areas worth checking:

More time to file does not mean more time to pay

One of the most important misconceptions surrounding the October deadline is that extending the tax return also postpones the underlying tax liability.

It generally does not.

Although a valid extension allows additional time to complete the return, tax may have been payable months earlier. Where insufficient tax was paid by the applicable payment deadline, interest and potentially penalties can continue to accrue.

Anyone expecting a liability when completing their extended return should therefore consider the payment position as well as the filing deadline.

Submit your FBAR

US taxpayers living overseas frequently hold bank, investment and other financial accounts outside the United States. These accounts may trigger reporting obligations, making it far better to identify a forgotten overseas account now than receive an unexpected IRS letter later.

Where the aggregate maximum value of foreign financial accounts exceeded $10,000 at any point during the calendar year, an individual may be required to file a Report of Foreign Bank and Financial Accounts (FBAR).

The FBAR has an original deadline of 15th April, but taxpayers who miss this deadline receive an automatic extension to 15th October. Unlike the extension for an individual income tax return, there is no requirement to separately request the FBAR extension.

Review foreign gifts and trust reporting

US persons who receive gifts or inheritances from foreign individuals exceeding $100,000 during the year may be required to file Form 3520. The reporting requirement does not generally create a tax liability, but penalties for failing to report can be severe.

For calendar-year individuals who have received an extension to file their income tax return, Form 3520 may also be extended to 15th October. Importantly, the Form 3520 deadline cannot generally be extended beyond this date simply because an overseas taxpayer obtains additional time to file their individual income tax return.

The penalties associated with failing to correctly report foreign trusts and gifts can be significant, making this an area that should be reviewed before the extended deadline rather than discovered afterwards.

Don't forget gift tax returns

A common misconception is that all tax filings follow the same extension timetable. Gift tax returns can have different filing requirements and should be reviewed separately to ensure all deadlines have been met.

Treat 15th October as more than a filing deadline

For internationally mobile families, expats and dual nationals, 15th October should be viewed as more than just a filing deadline. It is the final opportunity to take a step back and check that all related reporting obligations have been addressed.

Foreign accounts, gifts, trusts and cross-border investments often generate separate filing requirements, many of which carry penalties that can far exceed any tax actually due.

The good news is that most problems are entirely avoidable. A final review before the deadline can help ensure there are no unwelcome surprises, allowing you to put this year's US tax filing firmly behind you until next season arrives and the cycle begins all over again.

Glossary

FBAR (Foreign Bank and Financial Accounts Report): A report that certain US taxpayers must file when the total value of their foreign financial accounts exceeds $10,000 at any point during the year.

Form 3520: An IRS information return used to report certain foreign gifts, inheritances and transactions involving foreign trusts.

Filing extension: Additional time granted to submit a tax return, though it does not generally extend the deadline for paying tax owed.

Foreign trust: A trust established outside the United States that may create reporting obligations for US persons connected to it.