IRS Streamlined Foreign Offshore Procedure (SFOP) for Crypto

A UK-resident US citizen with unreported crypto gains usually has two separate liabilities to put right. HMRC's Crypto Disclosure Service settles the UK tax, interest and penalties. The IRS Streamlined Foreign Offshore Procedure (SFOP) settles the US side with no penalties, provided the failure was non-wilful. Both filings must be built on the same facts.

This guide is for American citizens and green card holders who live in the UK and hold, or have sold, bitcoin, other exchange tokens, NFTs or staking positions without reporting them fully in one country or both. It explains how the two routes work, the order to file them in, and where they can clash. That clash is sharpest where an HMRC behaviour finding appears to contradict the non-wilful certification the IRS asks you to sign. Jungle Tax prepares both sides as one piece of work, because a disclosure that is correct in London and inconsistent in Washington fixes only half the problem.

Why is this urgent in 2026?

Two developments have changed the risk. On 27 August 2026 HMRC published its annual Capital Gains Tax statistics. Its press release on the figures reported that 240 individuals declared more than £1 million each of cryptoasset gains in the 2024-25 tax year, totalling £717 million. Across all taxpayers, 17,600 people reported £1.38 billion of taxable crypto gains. HMRC also estimated that its education and compliance work produced an extra £168 million of Capital Gains Tax that year. The message is plain: HMRC knows who is declaring crypto gains, and so it can also see who is not.

The second development is data. The UK began implementing the OECD Cryptoasset Reporting Framework (CARF) in January 2026, and HMRC has said it will start receiving customer data from cryptoasset service providers in 2027. Our separate guide to the Cryptoasset Reporting Framework for UK-US dual filers covers what is collected and who reports it. The point here is narrower. Once that data arrives, a disclosure made afterwards is more likely to be treated as prompted. Under both HMRC's penalty rules and the IRS streamlined rules, what matters most is whether you came forward before the authority came to you.

On the US side, American brokers now issue Form 1099-DA, a US information return reporting digital asset sale proceeds to the IRS. It is a US broker form. UK platforms do not issue it, which is precisely why so many UK-resident Americans have gains that never appear on any document sent to the IRS. The absence of a 1099-DA does not mean there was nothing to report.

How the two regimes see the same crypto gain

The same disposal is taxed by both countries, but on different rules, in different currencies and in different tax years. Almost every error we see in self-prepared crypto disclosures comes from assuming one calculation serves both returns. It does not.

Issue	United States (IRS)	United Kingdom (HMRC)
Basis of taxation	Citizenship: worldwide income and gains, wherever you live	Residence: UK residents are taxed on their gains
Tax year	Calendar year, 1 January to 31 December	6 April to 5 April
Nature of crypto	Property; every sale, swap or spend is a disposal	Exchange tokens are chargeable assets; sales, swaps and spending are disposals
Currency of calculation	US dollars at the rate on each acquisition and disposal date	Sterling
Cost basis method	Specific identification where records support it, otherwise first-in, first-out, tracked wallet by wallet	Same-day rule, then 30-day rule, then the section 104 pool
Holding period	Short-term (one year or less) taxed at ordinary rates; long-term at preferential rates	No holding period distinction; CGT rates depend on your income band
Catch-up route	Streamlined Foreign Offshore Procedure: 3 years of returns, 6 years of FBARs, no penalties	Crypto Disclosure Service: 4, 6 or up to 20 years depending on behaviour, with interest and penalties
Behaviour standard	Non-wilful certification on Form 14653	Reasonable care, careless, or deliberate
Payment	Tax and interest sent with the submission	Within 30 days of submitting the disclosure

Why the same trade produces two different gains

Take a US citizen living in London who bought bitcoin in several tranches and sold part of the holding in February 2025. For HMRC, the disposal falls in the 2024-25 tax year. The cost is taken from the section 104 pool, unless the same-day or 30-day rules apply because tokens of the same kind were bought on the day of sale or in the following 30 days. For the IRS, the disposal falls in calendar 2025, and the cost is the dollar cost of the specific units identified, or the earliest units bought in that wallet. Each figure is converted at a different exchange rate on different dates. A sterling gain can even become a dollar loss, or the reverse, because of currency movements alone.

That is why the first deliverable in any engagement is a single reconciled transaction ledger. It covers every wallet and account from the first purchase, and each disposal is computed twice, once under each set of rules. Both disclosures are then drawn from that ledger. If they are prepared separately by different people with different spreadsheets, they will not agree, and a later enquiry in either country will find the gap.

How does the HMRC Crypto Disclosure Service work?

HMRC's guidance on how to tell HMRC about unpaid tax on cryptoassets sets out a voluntary disclosure route for Capital Gains Tax and Income Tax owed on exchange tokens such as bitcoin, NFTs and utility tokens. It is an online process, and an authorised agent can make the disclosure for you. The main features are these.

• You calculate the liability yourself. The disclosure has to include the tax, the late payment interest and a penalty you work out using HMRC's factsheets and calculators. HMRC can reject a penalty it considers too low.
• The lookback depends on behaviour. You must disclose 4 years if you took reasonable care and still got it wrong, up to 6 years if you were careless, and up to 20 years if the underpayment was deliberate.
• Payment is due within 30 days of submitting. HMRC normally issues a payment reference within 15 working days of the submission. The 30-day clock runs from the date you submit, not the date the reference arrives. If you cannot pay in time, contact HMRC before the deadline.
• HMRC may ask questions. It can request evidence, then accept or reject the offer in writing. A disclosure that turns out to be incomplete or inaccurate can lead to further penalties.

One point needs care. The gov.uk guidance does not say whether people who are not UK resident can use the service. This guide is written for current UK residents. A US citizen who has since left the UK, or whose residence status for the relevant years is in doubt, should take advice on the UK route before relying on the service.

Which HMRC behaviour category applies?

HMRC's categories are not labels you pick. They follow from the facts, and HMRC can challenge them. In broad terms:

• Reasonable care means you did what a prudent person would do: kept records, took advice on a genuinely uncertain point, and still made an error.
• Careless means a failure to take reasonable care. Examples include not keeping records of swaps, assuming crypto-to-crypto trades were not taxable, or never checking whether gains had to be reported.
• Deliberate means you knew the gains were taxable and chose not to report them, or knowingly gave HMRC incorrect information.

For inaccuracies in a return, the penalty ranges for an unprompted disclosure are commonly 0-30% of the extra tax for careless errors, 20-70% for deliberate errors and 30-100% for deliberate and concealed errors. Prompted disclosures carry higher minimums. Where no return was filed at all, HMRC's failure-to-notify penalties apply instead. The behaviour category therefore sets both the number of years disclosed and the penalty rate. As explained below, it can also decide which US route is still open to you.

How does the IRS Streamlined Foreign Offshore Procedure work for crypto?

The IRS's page on the Streamlined Foreign Offshore Procedures for taxpayers residing outside the United States sets the rules. For a US citizen or green card holder, the core requirements are:

• Non-residency. In at least one of the last three years for which the US return due date has passed, you had no US abode and were physically outside the United States for at least 330 full days. On a joint submission, both spouses must meet the test.
• Returns. File three years of US returns. Use original Form 1040 returns where none were filed, and amended Form 1040-X returns where the originals left out the crypto. Include every required information return, such as Form 8938 or Form 5471 where relevant.
• FBARs. File six years of delinquent FinCEN Form 114 reports where they were required.
• Certification. Sign Form 14653 confirming eligibility and that the failure was non-wilful. The certification must include a specific, credible narrative of the reasons.
• Payment. Pay all tax and statutory interest with the submission.

In return, the IRS does not assert failure-to-file, failure-to-pay, accuracy-related, information return or FBAR penalties for the covered years. Unlike the domestic version, the foreign procedure carries no miscellaneous offshore penalty. The IRS page also says that penalties already assessed for those years will not be abated, and that the protection falls away if a later examination finds fraud or a wilful FBAR violation. The procedure is not available to anyone already under IRS civil examination or criminal investigation.

Does crypto belong on the FBAR and Form 8938?

This is where many generalist guides go wrong. FinCEN Notice 2020-2 said that a foreign account holding only virtual currency is not currently reportable on the FBAR, although FinCEN has stated its intention to change the regulations. An account at a non-US platform that also holds sterling or dollar balances is a different matter. It may be reportable because of the fiat balance, so each platform needs to be looked at individually rather than on the basis of a rule of thumb. Form 8938 is less settled. The IRS has not issued definitive guidance on whether crypto held through a foreign platform is a specified foreign financial asset, so we take a considered, documented position on each holding rather than defaulting either way. Your UK bank and investment accounts, ISAs and pensions will almost always be reportable in their own right, and those omissions often travel alongside crypto ones. Our FBAR penalty calculator shows the exposure the streamlined route removes.

Is the UK tax creditable against the US tax?

Generally yes. For a US citizen whose tax home is in the UK, a gain on the sale of personal property can usually be treated as foreign source where the UK tax on it is at least 10%. The UK Capital Gains Tax can then be claimed as a foreign tax credit against the US tax on the same gain. Because UK rates on crypto gains are often higher than US long-term rates, the credit frequently eliminates most or all of the US tax on long-term gains. Short-term gains taxed at US ordinary rates, differences in the amount of the gain, and mismatched tax years can still leave a US balance to pay. The credit can only be computed properly once the UK liability for each year is known. That is the first reason sequencing matters.

In what order should the two disclosures be made?

There is no statutory order, but in our experience this sequence produces the cleanest result for a UK-resident American.

1. Rebuild the full history first. Pull every exchange statement, wallet address and on-chain record from the first purchase. A UK lookback of 6 or 20 years, and FBARs covering six years, both need data from before the three US return years. Missing cost records are the most common reason both disclosures overstate the gain.
2. Compute each disposal twice. Produce the sterling gain on the April-to-April year using UK matching rules, and the dollar gain on the calendar year using US identification rules. Classify staking rewards, airdrops and mining income separately for each country.
3. Settle the behaviour analysis before signing anything. Decide, candidly and with evidence, whether the UK behaviour is reasonable care, careless or deliberate. Then test whether the Form 14653 narrative can honestly describe the same facts as non-wilful. If it cannot, stop and reconsider the US route before any filing is made.
4. Quantify the UK liability. Calculate tax, interest and penalty for each UK year, so the UK tax attributable to each US year is known for the foreign tax credit.
5. Decide the foreign tax credit timing. A taxpayer claiming credits on the paid basis may only be able to claim UK tax in the year it is actually paid, which here could be 2026. An election to claim credits as they accrue can relate the tax back to the year of the gain. This decision shapes the amended returns and has to be made before they are drafted.
6. File both within a short window. Submit the HMRC disclosure and the streamlined package close together, keeping in mind that HMRC's 30-day payment clock starts on submission. Filing both close together means neither authority learns of the problem from the other first.
7. Get current on both returns going forward. File the UK Self Assessment for 2025-26 by 31 January 2027 and the 2026 US return on time, with crypto reported correctly. A catch-up followed by a new omission undermines both disclosures.

Why must both disclosures tell the same story?

The UK-US tax treaty contains an exchange of information article, and the two authorities also exchange financial account data under the FATCA intergovernmental agreement and the Common Reporting Standard. Assume that anything you tell one authority could be seen by the other. Three kinds of inconsistency cause real problems.

• Different transaction totals. If the HMRC disclosure reports proceeds from four platforms and the US returns reflect only two, the omission is obvious to anyone comparing the files.
• Different explanations. A Form 14653 narrative that says you did not know crypto swaps were taxable sits badly beside an HMRC disclosure accepting that you ignored an HMRC letter about cryptoassets.
• Different timelines. If the UK disclosure says you started trading in 2019 but the US narrative describes a first purchase in 2022, one of them is wrong, and the IRS certification is signed under penalty of perjury.

Consistency does not mean the numbers match. They will not, for the reasons explained above. It means both filings rest on one ledger, one factual chronology and one honest account of why the gains went unreported. Once those are fixed, the sterling and dollar calculations are technical conversions.

Can you certify non-wilful to the IRS after an HMRC careless or deliberate finding?

This is the central tension, and most guides on either procedure ignore it. The IRS treats non-wilful conduct as conduct due to negligence, inadvertence, mistake, or a good faith misunderstanding of the law. HMRC's categories use different words, but they map onto that standard in a fairly predictable way.

Reasonable care or careless

An HMRC careless finding is a failure to take reasonable care. That is very close to negligence, which the IRS expressly includes within non-wilful conduct. A UK-resident American who never checked whether crypto swaps were reportable, kept poor records, and accepts a careless categorisation in the UK can usually still give a truthful non-wilful certification to the IRS, if the narrative is specific and the facts support it. A reasonable care case is easier still.

Deliberate

A deliberate categorisation means you accept that you knew the gains were taxable in the UK and chose not to report them. It is very difficult to certify to the IRS, under penalty of perjury, that failing to report the same gains in the United States was a mere mistake. The IRS also treats wilful blindness and reckless disregard as wilful. There can be genuine cases where the facts differ between the two countries. For example, someone may have known about UK CGT but honestly not understood that US citizenship created a separate American liability while living abroad. Those cases need careful, evidenced analysis, not an assumption.

Where the honest answer is that the conduct was wilful, the streamlined procedure is not the right route. The alternative is usually the IRS Criminal Investigation Voluntary Disclosure Practice, which carries higher penalties but addresses wilful non-compliance directly. Filing a streamlined certification that cannot be squared with an HMRC deliberate finding risks losing the streamlined penalty protection and creating a much more serious US problem. This decision should be taken before either disclosure is submitted, not after HMRC has accepted a behaviour category.

What if HMRC changes the category?

HMRC can review a self-assessed behaviour category and substitute its own view. If a disclosure made as careless is re-categorised as deliberate after the streamlined package has been filed, the two positions diverge. That is why the behaviour analysis in step 3 has to be evidence-based and conservative. Describing the facts candidly from the outset is far safer than choosing the most favourable label in each country.

Correcting a wrong "No" to the Form 1040 digital asset question

Since the 2019 tax year, Form 1040 has asked whether you received, sold, exchanged or otherwise disposed of virtual currency, now described as digital assets. The IRS's digital assets guidance explains who must answer "Yes". Broadly, it is anyone who sold, swapped, spent, or received crypto as income, including through staking or an airdrop. Simply buying crypto with cash and holding it is generally a "No".

Many UK-resident Americans ticked "No" out of habit, often because a preparer never asked. The question is signed under penalty of perjury with the rest of the return, so a wrong answer is a misstatement to correct, not a formality to ignore.

• Within the three streamlined years: the amended Form 1040-X corrects the answer to "Yes" alongside the added gains, and the Form 14653 narrative should explain how the incorrect answer came about.
• Earlier years: where a wrong answer in an earlier year hides no unreported tax, it is usually a matter for judgement. We assess it case by case and do not amend automatically.
• Current and future years: answer the question accurately. A "Yes" with properly reported gains after a streamlined submission is exactly what the IRS expects to see.

The answer to this question is also evidence. An IRS reviewer comparing a "No" with an HMRC disclosure showing years of active trading will look closely at the non-wilful narrative. The explanation for the wrong answer has to fit the same account of events given to HMRC.

Crypto-specific points that change the numbers

• Crypto-to-crypto swaps are disposals in both countries. They are the single largest source of unreported gains we see, because no cash ever reached a bank account.
• Staking and similar rewards are generally taxable as income in the US when received, and HMRC's cryptoassets manual treats many rewards as income too. The two countries may value and time them differently, and a later sale of the reward tokens is a separate disposal in each.
• UK annual exempt amount. The CGT exemption fell to £6,000 for 2023-24 and £3,000 from 2024-25. Many people who assumed they were below the threshold in earlier years were not in later ones.
• UK CGT rates changed mid-year. Rates on most gains rose to 18% and 24% for disposals from 30 October 2024, so the 2024-25 UK calculation has to split disposals by date.
• Losses. UK losses must generally be claimed within four years of the end of the tax year in which they arose. US capital losses carry forward, subject to the annual limit against ordinary income. Losses can be valuable in both countries, so they should be captured in the reconstruction.
• Lost or scammed tokens. These are treated differently in each country and should be analysed separately, not netted off informally.

HMRC's Cryptoassets Manual sets out its detailed view on pooling, staking, airdrops and the location of exchange tokens. We apply it line by line on the UK computation.

What about HMRC letters and IRS contact?

If HMRC has already written to you about cryptoassets, a disclosure made now is likely to be treated as prompted, with a higher penalty floor. It remains far better than waiting for an enquiry. An HMRC letter does not by itself stop you using the IRS streamlined procedure, which is barred only by IRS examination or investigation. It does make the US narrative harder to write if the letter was ignored for a long time. If the IRS has contacted you about the years in question, the streamlined route may no longer be open, and you should take advice before filing anything.

How Jungle Tax prepares a dual crypto disclosure

We are a return preparation and compliance practice, not a wealth structuring adviser. For a UK-resident American with unreported crypto, the engagement covers the complete transaction reconstruction, the dual computations, the HMRC Crypto Disclosure Service submission with the interest and penalty calculations, and the full streamlined package: three years of returns, six years of FBARs, Form 8938 where relevant and the Form 14653 narrative. Both are drafted from one file by one team. Clients whose disclosures involve significant sums or complex holdings will find more on our high net worth service and on our work as US-UK tax accountants. Our UK tax services cover the ongoing Self Assessment returns once you are compliant.

If you have crypto gains that have not been reported in the UK, the US, or both, the order in which you act and the story you tell matter as much as the numbers. Speak to us before you file either disclosure. Contact our cross-border team for a confidential consultation, and we will map both disclosures, the behaviour analysis and the foreign tax credit position before anything reaches HMRC or the IRS.