IRS Streamlined Domestic Offshore Procedure (SDOP): 5% Penalty

Under the IRS Streamlined Domestic Offshore Procedure (SDOP), a US-resident American pays a 5% miscellaneous offshore penalty in place of FBAR and information-return penalties. The base is the highest single year-end total of the foreign assets that were not properly reported, measured across the covered tax-return and FBAR years and converted into US dollars.

For an American who has come home from London (a private-equity principal, a hedge-fund partner, a senior banker) with UK current accounts, ISAs, a general investment account and cash savings still open, that one paragraph hides most of the work. The penalty is not 5% of everything you hold in Britain. It is 5% of a figure built asset by asset and year by year, and a single reporting decision made in 2023 can move the number by tens of thousands of dollars. This guide covers eligibility first, then works through the penalty-base computation the way a preparer would build it. Every figure below is illustrative and should be checked against your own records and current IRS guidance before you rely on it.

Who is eligible for SDOP after moving back from the UK?

The domestic procedure is for taxpayers who cannot use the foreign version. According to the IRS page on the Streamlined Domestic Offshore Procedures, you must satisfy all of the following:

• You fail the foreign non-residency test. SDOP is available only if you do not meet the non-residency requirement of the Streamlined Foreign Offshore Procedures. For a joint return, one or both spouses must fail it.
• You filed US returns. A US tax return, where one was required, must have been filed for each of the most recent three years whose due date (or properly extended due date) has passed. The procedure amends returns. It cannot be used to file delinquent originals.
• You under-reported foreign income. You must have failed to report gross income from a foreign financial asset and pay the tax on it. You may also have missed FBARs and international information returns such as Form 8938.
• Your conduct was non-wilful. The IRS defines non-wilful conduct as conduct due to negligence, inadvertence or mistake, or a good-faith misunderstanding of the law.
• You are not under examination. An open IRS civil examination for any year, or a criminal investigation, generally closes the door.

Test the foreign procedure before you accept the 5%

This is the step generalist guides skip, and for recent returners it is often the most valuable one. The Streamlined Foreign Offshore Procedures carry no miscellaneous offshore penalty. A US citizen generally meets their non-residency test if, in at least one of the three most recent tax years in the covered period, they had no US abode and were physically outside the United States for at least 330 full days. If you left London part-way through a year, the year before your move may still qualify, but only while it remains inside the rolling three-year window. As of late 2026 the covered tax years are typically 2023, 2024 and 2025. A taxpayer who moved back in spring 2023 has probably already lost 2022 from that window. One who moved back in 2024 may still be able to use 2023. Timing your submission against the rolling window can be worth the entire 5% penalty, so it should be checked before anything else.

The non-wilful certification on Form 14654

Every SDOP submission includes a signed Form 14654 certification, made under penalties of perjury. It confirms your eligibility, that all required FBARs have now been filed, that the failures were non-wilful, and that the penalty you computed is correct. It must also include a narrative of the specific reasons for the failures. For a finance professional, the IRS will read that narrative knowing the author is sophisticated. "I did not know" is rarely enough. What helps is a factual, documented account: that a UK adviser told you an ISA was "tax-free", with no mention of the US position, or that a US preparer was never told the GIA existed. The narrative has to be true and has to agree with the documents. That certification is what protects you, and it is where weak submissions tend to fail.

What exactly is the 5% miscellaneous offshore penalty?

The penalty is a Title 26 amount that you calculate and pay with your submission. In return, the IRS generally does not assert accuracy-related penalties, information-return penalties or FBAR penalties for the covered years, unless it later finds fraud or wilfulness. The rate is 5%. The base is the highest aggregate balance or value of the foreign financial assets subject to the penalty, and "subject to the penalty" is the important qualifier.

The two covered periods

• Covered tax return period: the most recent three tax years whose due date, or properly extended due date, has passed. You file Form 1040-X for each of these years.
• Covered FBAR period: the most recent six years whose FBAR due date has passed. You file any missing or incorrect FBARs electronically for each of these years.

The two periods overlap. On a typical late-2026 submission, the FBAR period runs 2020 to 2025 and the tax return period runs 2023 to 2025. The penalty base looks across all of those years and picks the single highest year-end total. Confirm the exact years against the date you will actually post the package, because a 15 October or 15 April deadline passing can roll both windows forward by a year.

Which UK assets enter the penalty base?

An asset is included in a given year if any of three triggers applies to it for that year:

1. FBAR trigger (any year in the FBAR period): the asset should have been reported on an FBAR for that year but was not.
2. Form 8938 trigger (tax return years only): the asset should have been reported on Form 8938 for that year but was not.
3. Income trigger (tax return years only): the asset was properly reported, but gross income from it was not reported on the return for that year.

The reverse follows. An asset that was correctly disclosed on the FBAR, correctly disclosed on Form 8938 where required, and whose income was fully reported in a given year is left out of the base for that year. The test is applied year by year and asset by asset. It is not an all-or-nothing judgement on your UK holdings.

How the three triggers apply to typical UK holdings

UK asset	UK (HMRC) treatment	US (IRS) treatment	Typical SDOP penalty-base exposure
Current or deposit account	Interest taxable, with a personal savings allowance while resident	Interest taxable; FBAR and possibly Form 8938	Often reported on the FBAR but omitted from 8938, which still triggers inclusion in tax years
Cash ISA	Interest exempt	No US recognition; interest fully taxable	Frequently omitted everywhere, so included in every covered year
Stocks and shares ISA	Dividends and gains exempt	Fully taxable; UK funds inside are commonly PFICs	High exposure: missed income plus missed PFIC reporting
General investment account (GIA)	Taxable; reporting-fund status matters	Taxable; UK collective funds are commonly PFICs	Account often on the FBAR, but income misreported, so included in tax years
Fixed-term savings bond	Interest taxable on maturity or as paid	Interest generally taxable as it accrues or is credited	Timing mismatches create unreported-income years
UK workplace or personal pension	Tax-relieved; growth sheltered	Treaty relief may defer growth; reporting still required	Treatment in the base is fact-specific and should be analysed separately

Note that the UK's ISA wrapper has no effect for US purposes. The US-UK income tax treaty does not extend ISA exemptions to US citizens. A London professional who sensibly maxed out ISA subscriptions every April may therefore have years of unreported US income, and possibly PFIC exposure, from an account HMRC regarded as entirely tax-free.

The FBAR-filed, 8938-missed trap

The most common surprise for returners is an account that was on every FBAR, because the client knew about FinCEN Form 114, but never appeared on Form 8938. Once you are back in the US, the 8938 thresholds for US residents are much lower than those for taxpayers abroad: commonly cited as more than $50,000 at year end or $75,000 at any time for single filers, and double those figures for joint filers (verify the current thresholds). A substantial UK brokerage account will almost certainly cross them. A timely FBAR does not cure a missing 8938, so that account comes back into the base for every tax-return year in which the 8938 should have been filed.

How is the highest aggregate year-end balance calculated?

The IRS method is short. For each year in the covered periods, add up the year-end account balances and year-end asset values of every asset that is subject to the penalty in that year. Then take the highest annual total. That figure multiplied by 5% is the penalty. Three details matter in practice.

Year-end, not maximum, values

The FBAR asks for the maximum value of each account during the year. The SDOP penalty base uses the year-end balance. A large bonus that passed through a UK current account in March and left by December raises your FBAR maximum value but not your penalty base. Preparers who simply carry the FBAR maximums into the penalty worksheet overstate the penalty, sometimes by a lot.

Converting sterling into US dollars

Your UK statements are in pounds, and the penalty is paid in dollars. The usual practice, consistent with FBAR reporting, is to convert each year-end sterling balance at the Treasury Reporting Rates of Exchange for the last day of the calendar year. Verify the rate source for your filing and use it consistently. Do not use the yearly average exchange rates, which are generally used for converting income. Because sterling has moved sharply against the dollar in recent years, exchange rates alone can change which year produces the highest total, even when the sterling balances barely moved.

Joint accounts and joint filers

Married couples filing jointly compute one combined penalty base. Accounts held jointly with a non-US spouse (common after years in London) raise questions about how much of the balance belongs to the US taxpayer. The answer depends on ownership, contributions and the account terms. It should be documented rather than assumed, and the approach recorded in the work papers that support Form 14654.

Worked example: a private-equity principal back in New York

Consider an illustrative American client who spent nine years in London with a private-equity firm and moved back to New York in early 2023. He has always filed US returns and FBARs, but his London-era preparer worked only from his UK payslips and the bank accounts he mentioned. He still holds four UK assets:

• Asset A, UK current account: on every FBAR, on Form 8938 for 2023 to 2025, interest fully reported. Not subject to the penalty in any year.
• Asset B, stocks and shares ISA: never on an FBAR or 8938; dividends and gains never reported. Subject in every year of both periods.
• Asset C, GIA brokerage account: on every FBAR and on Form 8938, but income from accumulating UK funds was never reported. Excluded for 2020 to 2022 (FBAR correct; tax years not in the return period). Subject for 2023 to 2025 under the income trigger.
• Asset D, cash savings account opened in 2019: omitted from FBARs and 8938. Subject in every year.

Using illustrative year-end values already converted to USD at year-end rates:

Year (period)	B: ISA	C: GIA	D: Savings	Aggregate subject to penalty
2020 (FBAR only)	$280,000	Excluded	$150,000	$430,000
2021 (FBAR only)	$330,000	Excluded	$200,000	$530,000
2022 (FBAR only)	$300,000	Excluded	$260,000	$560,000
2023 (FBAR + tax)	$360,000	$900,000	$240,000	$1,500,000
2024 (FBAR + tax)	$410,000	$1,050,000	$120,000	$1,580,000
2025 (FBAR + tax)	$450,000	$980,000	$60,000	$1,490,000

The highest aggregate is 2024 at $1,580,000, so the illustrative miscellaneous offshore penalty is $79,000. Asset A, the account he reported properly, adds nothing at any point.

Now suppose the GIA income had been reported correctly in 2023 to 2025. Asset C drops out of every year, the highest aggregate becomes 2023 at $600,000, and the penalty falls to $30,000. One unreported stream of fund income, perhaps a few thousand dollars of accumulating distributions a year, accounts for $49,000 of penalty. That is why the asset-by-asset analysis matters, and why each asset's income should be checked before it is assumed to fall in the base.

Separately, the amended returns will show the tax due on the ISA and GIA income, possibly including PFIC computations, plus statutory interest. These are paid with the submission alongside the penalty. UK tax paid on UK-taxable income may be creditable, but UK-exempt ISA income has usually borne no UK tax to credit.

How does SDOP compare with outcomes outside the programme?

The 5% looks expensive until you set it against the alternatives. The comparison below is general, the statutory amounts are inflation-adjusted, and the figures should be verified for your years.

Route	When it fits	Penalty position (general)	Main risk
Streamlined Foreign Offshore Procedures	Non-residency test met in a covered year	No miscellaneous offshore penalty	Window closes as years roll forward
Streamlined Domestic Offshore Procedure	US resident, returns filed, non-wilful, unreported income	5% of highest aggregate penalty base; other covered penalties generally not asserted	Certification scrutiny for sophisticated filers
Delinquent FBAR / international information return procedures	No unreported income, only missed forms	Often no penalty if the IRS accepts reasonable cause	Not available where income was omitted
Quiet amended returns, no programme	Not recommended	Full exposure: non-wilful FBAR penalties per report, $10,000-plus 8938 penalties, 20% accuracy-related penalties	Treated as if no disclosure was made
Voluntary disclosure practice	Wilful conduct	Substantially higher civil penalties	Required where non-wilfulness cannot honestly be certified

For context, the non-wilful FBAR penalty is inflation-adjusted to a little over $10,000 per report following the 2023 judicial ruling that the penalty applies per report, and Form 8938 failures carry a $10,000 base penalty with continuation penalties of up to $50,000 more per form. Wilful FBAR penalties can reach the greater of an inflation-adjusted six-figure amount or 50% of the balance. For a high-balance client with several missed forms across six years, the arithmetic usually favours SDOP comfortably. The exception is where the facts point towards wilfulness, and then SDOP is the wrong route entirely.

What about the UK side after you have left?

SDOP is purely an IRS procedure, and HMRC is not involved. The UK position still needs checking, though, because the US amended returns will claim foreign tax credits for UK tax, and those credits must match what was actually paid. Points to confirm with your UK records:

• Your final UK resident year. If split-year treatment applied when you left, UK income after departure may fall outside the UK charge. Make sure your final Self Assessment return reflects this.
• UK income while non-resident. Non-residents generally remain taxable in the UK on UK-source income, but UK savings interest and dividends often fall within the limited "disregarded income" rules. HMRC's guidance on tax on UK income if you live abroad sets out the framework.
• ISAs after departure. You can keep an existing ISA and its UK tax benefits after becoming non-resident, but you cannot normally add new subscriptions. See HMRC's ISA guidance for people moving abroad. None of this changes the US position. The ISA stays in the US penalty base until it is properly reported.
• Treaty sourcing and credits. Under the US-UK treaty, the UK may tax UK-source income first, with the US giving credit. On ISA and other UK-exempt income no UK tax is paid, so the full US tax falls due.

Building the submission: a preparer's sequence

1. Confirm the route. Test the foreign non-residency requirement against each covered year before settling on SDOP.
2. Inventory every UK asset across all six FBAR years, including dormant accounts, fixed-term bonds and accounts held in joint names.
3. Assign triggers asset by asset, year by year. Record whether each asset was on the FBAR, on Form 8938, and whether its income was reported.
4. Collect year-end statements and convert at the year-end Treasury rate. Keep the maximum values separately for the FBARs.
5. Prepare three Forms 1040-X with all required information returns (Forms 8938, 8621 for PFICs, and others), marked "Streamlined Domestic Offshore" at the top of the first page as the IRS instructions require.
6. File the missing or amended FBARs electronically, selecting the streamlined reason for late filing.
7. Draft the Form 14654 narrative and penalty schedule. Then reconcile the penalty base to the statements line by line.
8. Pay the tax, interest and penalty with the paper submission to the dedicated SDOP address.

The IRS does not issue a formal acceptance letter. Your protection depends on the quality of the package: whether the penalty base can be reconciled, whether the narrative is consistent, and whether the returns are complete. You can model the stand-alone FBAR exposure on our FBAR penalty calculator, read related scenarios in our cross-border guides, or see how Jungle Tax supports internationally mobile families through our high-net-worth practice and US-UK tax accountants.

Getting the number right the first time

The SDOP penalty is self-assessed. If you overstate it, nobody will refund the difference. If you understate it, or describe the facts carelessly, you put at risk the protection you are paying for. For returners with significant UK wealth, the key tasks are deciding which assets belong in which years, applying year-end sterling conversion, and excluding properly reported assets. Getting these right typically saves far more than the cost of doing it carefully. If you are back in the US with UK accounts that were never fully reported, contact our cross-border team for a confidential consultation. We will confirm whether the foreign procedure is still open to you, build your penalty base asset by asset, and prepare a complete, defensible submission.