Introduction
The market for US expat tax advice in the United Kingdom is fragmented and largely unregulated from the US side. Any adviser can claim to specialize in Streamlined submissions. Not all of them do it well.
Choosing the wrong IRS Streamlined Filing Experts can result in an incomplete submission that fails to obtain the penalty waiver. This incorrect non-wilfulness certification attracts IRS examination, a submission that omits Form 8621 and leaves the statute of limitations open indefinitely, or an FBAR prepared with year-end rather than peak balances. None of these outcomes is reversible without a high additional cost.
This guide explains how to vet a Streamlined specialist before you engage. It covers the qualifications to look for, the questions to ask, the warning signs of an unqualified or careless adviser, and what a proper engagement looks like, from initial contact to submission acceptance. Contact Jungle Tax at Https://www.jungletax.co.uk/ to discuss your Streamlined submission.
What Are IRS Streamlined Filing Experts?
The Qualification Standard
IRS Streamlined Filing Experts are US-qualified tax professionals — typically IRS Enrolled Agents or US-licensed CPAs — with specialized experience preparing Streamlined Foreign Offshore Procedures submissions for Americans living outside the United States. The IRS Enrolled Agent credential is the highest US federal tax credential available to a tax practitioner. It requires passing a three-part examination administered by the IRS and completing ongoing continuing education requirements.
An IRS Enrolled Agent has unlimited rights to represent clients before the IRS — including in examination proceedings. A UK accountant without EA or CPA status cannot represent a client before the IRS, cannot sign a US federal return as a paid preparer, and cannot prepare a FBAR on the client’s behalf under the FinCEN regulations. A UK accountant who offers to prepare a Streamlined submission without US credentials is not a qualified Streamlined specialist.
What Genuine Expertise Looks Like
Genuine IRS Streamlined Filing Experts understand: the FBAR peak balance calculation and the difference between year-end and peak values; the Form 8621 PFIC reporting requirement and the mark-to-market election; the Foreign Tax Credit calculation and the passive/general basket separation; the non-wilfulness standard and what makes a credible certification narrative; and the interaction between the UK self-assessment and the US federal return for the same income period.
An adviser who does not know what Form 8621 is, cannot explain the peak balance requirement, or does not know that the UK self-assessment and the US federal return cover overlapping periods, is not a genuine Streamlined specialist.
The IRS guidance on IRS Enrolled Agents is published at:
https://www.irs.gov/tax-professionals/enrolled-agents/enrolled-agent-information
Why the Right Specialist Matters for UK-Based Americans
A UK-based American has a dual filing obligation — the UK self-assessment and the US federal return. The two returns must be consistent. The income on the UK self-assessment is the source data for the FTC calculation on the US return. An adviser who prepares the US return without seeing the UK self-assessment — or who does not understand the UK system — cannot optimize the FTC correctly. A genuine IRS Streamlined Filing Experts practice in the UK employs or works closely with UK-qualified tax practitioners to ensure both returns are prepared correctly and consistently.
Why Hiring the Right IRS Streamlined Filing Experts Matters in 2026
The IRS is Scrutinizing Non-Wilfulness Certifications More Closely
Following the Supreme Court’s 2023 decision in Bittner v United States, the IRS has increased its focus on the quality of non-wilfulness certifications. A poorly drafted certification — one that is vague, inconsistent with the facts, or internally contradictory — is more likely to attract IRS scrutiny than a well-crafted narrative that accurately reflects the taxpayer’s specific circumstances. An unqualified adviser who provides a generic certification template is not providing adequate protection.
An Incomplete Submission Does Not Obtain the Penalty Waiver
The Streamlined program’s penalty waiver applies only to a complete and accurate submission. A submission that omits Form 8621 — required for every non-US fund held by the taxpayer — is not complete. A submission that uses year-end FBAR balances rather than peak balances is inaccurate. Neither submission obtains the full penalty waiver. The cost of correcting an inadequate submission — re-preparing returns, re-filing FBARs, addressing IRS correspondence — typically exceeds the fee saving from using a cheaper adviser initially.
Our guide to the cost of not getting specialist help quantifies the penalty exposure that a correct submission eliminates.
The Market Contains Many Unqualified Providers
The expat tax market in the United Kingdom contains a significant number of providers who market Streamlined services without the qualifications to deliver them correctly. Some are UK accountants without US credentials. Some are online platforms that use templated returns with minimal adviser review. Some are general practitioners who have prepared one or two Streamlined submissions but lack the depth of knowledge for complex cases. Vetting the adviser before engaging is the client’s responsibility — the IRS has no mechanism to protect a taxpayer from a poorly prepared submission filed on their behalf.
Green Flags — What to Look for in a Streamlined Specialist
Verifiable US Credentials — EA or CPA
The most important green flag is verifiable US credentials. An IRS Enrolled Agent’s credential can be verified through the IRS’s online EA search tool, which confirms the adviser’s name, credential status, and disciplinary history. A US CPA’s credentials can be verified through the relevant state board of accountancy. Ask the adviser for their EA number or CPA license number and verify it independently. An adviser who cannot provide a verifiable credential is not a qualified US tax practitioner.
Knowledge of UK Tax — Not Just US Tax
A genuine Streamlined specialist for UK-based Americans understands the UK self-assessment, UK income tax rates, UK pension rules (including the Article 17 SIPP election), and the UK CGT rules. They prepare both the UK and US returns for the year, ensuring consistency between them. An adviser who says they handle only the US side and leaves the UK return to another adviser — without coordination — is not providing a complete service. Ask the adviser: Do you also prepare the UK self-assessment? How do you coordinate the income figures across both returns?
Specific Knowledge of Form 8621 and PFIC Reporting
Form 8621 is required annually for every non-US fund, including UCITS funds held in an ISA or SIPP. The omission of Form 8621 leaves the statute of limitations open indefinitely on the entire US return for that year. A genuine Streamlined specialist asks specifically about investment portfolios, ISAs, and SIPPs during the initial engagement — and identifies every PFIC position before the submission is prepared. Ask the adviser: What is Form 8621, and when is it required? If they cannot answer clearly, they are not qualified for complex submissions.
A Clear Written Scope and Fixed Fee
A professional Streamlined specialist provides a written engagement letter before any work begins. The letter specifies exactly what will be prepared — how many years of returns, how many years of FBARs, which additional forms are included, and what is excluded from the scope. The fee is fixed — not estimated. An adviser who provides only a verbal estimate or fails to produce a written scope before starting work is not operating to professional standards. Ask for the engagement letter before paying any deposit.
Transparency About the Non-Wilfulness Assessment
A qualified specialist conducts a wilfulness assessment before agreeing to prepare a Streamlined submission. They ask specific questions about the taxpayer’s awareness of the filing obligation, any prior advice received, and any steps taken that might suggest deliberate concealment. They explain the non-wilfulness standard clearly and give an honest assessment of whether the taxpayer’s facts support the certification. An adviser who agrees immediately to prepare a Streamlined submission without asking any questions about the taxpayer’s knowledge or conduct is not conducting an adequate assessment.
Red Flags — Warning Signs of an Unqualified Adviser
No Verifiable US Credentials
An adviser who cannot provide a verifiable EA number or CPA license is not a qualified US tax practitioner. A UK accounting qualification — ACA, ACCA, CIMA — does not confer the right to prepare US federal returns or sign FBARs as a paid preparer. A UK accountant who offers to prepare a Streamlined submission using their UK credentials is not operating within their permitted scope. Verify credentials independently before engaging.
Guaranteed Penalty Waiver
No adviser can guarantee that a Streamlined submission will be accepted or that the penalty waiver will apply. The IRS reviews submissions and can reject them — or open an examination — if the facts do not support the non-wilfulness certification, or if the submission is incomplete. An adviser who guarantees acceptance or no penalty is either uninformed about how the program works or is misrepresenting their service. This is one of the clearest red flags in the market.
No Mention of Form 8621 During the Initial Assessment
Form 8621 is one of the most commonly omitted forms in Streamlined submissions prepared by unqualified advisers. An adviser who takes on a Streamlined engagement without asking about the client’s investment portfolio — specifically about non-US funds, ISAs, and SIPPs — is not conducting an adequate assessment of the required forms. If the initial consultation does not include a question about investments, the adviser is likely to produce an incomplete submission.
Year-End FBAR Balances — Not Peak Balances
The FBAR requires the maximum value of each account at any point during the calendar year — not the year-end balance. An adviser who asks for year-end bank statements — rather than monthly or quarterly statements for the full year — is preparing the FBAR with incorrect balance figures. This is a material error. Ask the adviser specifically: Do you use peak balances or year-end balances for the FBAR? The correct answer is peak balances. If the adviser is uncertain, they are not qualified.
Using the OVDP — Which Was Discontinued in 2018
The IRS Offshore Voluntary Disclosure Program was discontinued on 28 September 2018. An adviser who mentions the OVDP as an available option is either uninformed or years out of date on the program. This red flag indicates that the adviser’s knowledge of the Streamlined procedures and the current voluntary compliance landscape may also be inadequate.
How to Vet a Streamlined Specialist — A Step-by-Step Process
Step One: Verify the US Credential
Use the IRS’s online EA verification tool — available at www.irs.gov — to confirm the adviser’s Enrolled Agent status and check for disciplinary history. For a CPA, use the relevant state board of accountancy’s online license verification. Do not rely on the adviser’s website or marketing material alone. Verification takes less than five minutes and confirms the most fundamental qualification requirement.
Step Two: Ask the Initial Assessment Questions
Before engaging, ask the adviser four questions. First: Do you prepare the UK self-assessment as well as the US return? Second: What is Form 8621, and how do you handle PFIC positions in a Streamlined submission? Third: Do you use peak balances or year-end balances for the FBAR? Fourth: What is your process for assessing non-wilfulness before certifying?
The answers reveal the adviser’s actual knowledge. A qualified specialist answers all four questions correctly and specifically. An unqualified adviser hedges, asks what Form 8621 is, or does not know the peak balance requirement.
Step Three: Request the Written Engagement Letter
Before paying any fee, request the written engagement letter. Review the scope carefully. Confirm that the letter specifies: how many years of federal returns, how many years of FBARs, which additional forms are included (Form 8621, Form 8938, Form 5471 if applicable), what is excluded from scope, the fixed fee, and the timeline. An engagement letter that omits these specifics is inadequate.
Step Four: Confirm the FTC Optimization Approach
Ask the adviser: How do you handle the Foreign Tax Credit for the UK employment income in the Streamlined submission? A qualified specialist explains that they obtain the client’s UK income tax figures — from the self-assessment or PAYE records — and apply the FTC to minimize the additional US tax owed. An adviser who cannot explain the FTC calculation is not providing a complete service.
Step Five: Check the Annual Program Scope
Before committing to the Streamlined submission, ask the adviser about the annual compliance program. What will be filed each year? What is the annual fee? How is the PFIC mark-to-market election maintained? A genuine specialist establishes the annual program before the submission closes — so the client is never non-compliant again. An adviser who focuses only on the submission and does not discuss the annual program is providing an incomplete service.
The IRS guidance on choosing a tax professional is published at:
https://www.irs.gov/tax-professionals/choosing-a-tax-professional
Case Study — The Cost of Choosing the Wrong Adviser
The Initial Engagement
Fiona is a US citizen living in Manchester. She had been non-compliant for seven years. She engaged a UK accountancy firm that marketed US expat tax services on its website. The firm did not have IRS Enrolled Agent status. The fee was £900 — significantly below the market rate for a complete Streamlined submission.
The firm prepared three years of US federal returns and six years of FBARs. The FBARs used year-end balances from annual bank statements — not peak balances from monthly statements. The submission did not include Form 8621 for the two UCITS funds Fiona held in her Stocks and Shares ISA. The non-wilfulness certification was two sentences — a generic statement that Fiona had not known about the filing requirement.
What Went Wrong
The IRS sent a correspondence inquiry about the submission eighteen months later. The inquiry flagged the missing Form 8621 filings, which left the statute of limitations open indefinitely on all three returns. The IRS also noted that the FBAR balances appeared to be year-end figures rather than peak values — inconsistent with the FATCA data the IRS held for Fiona’s accounts.
Fiona contacted Jungle Tax. The assessment identified three problems: the missing Form 8621 for two years (leaving those returns open indefinitely), the understated FBAR peak balances (creating accuracy risk on the FBAR submissions), and the inadequate non-wilfulness narrative (which did not address the specific facts of Fiona’s case). The original submission had not obtained the full penalty waiver because it was incomplete.
The Remediation Cost
Jungle Tax prepared corrected FBARs with accurate peak balances, supplemental Form 8621 filings for the two open years, and a revised and expanded non-wilfulness narrative that addressed the IRS’s specific concerns. The remediation cost — adviser fees plus IRS correspondence management — was £3,200. The total cost of the engagement, including the original £900 and the £3,200 remediation, was £4,100 — significantly more than a correctly prepared submission would have cost from the outset.
Contact our IRS Streamlined Filing Experts team at hello@jungletax.co.uk or 0333-8807974 to discuss your Streamlined submission.
Common Mistakes When Hiring a Streamlined Specialist
Choosing on Price Alone
The Streamlined submission is not a commodity service. The quality of the non-wilfulness narrative, the completeness of the Form 8621 filings, and the accuracy of the FBAR peak balances all affect whether the submission obtains the full penalty waiver. A submission that costs £900 but omits Form 8621 and uses year-end FBAR balances does not obtain the penalty waiver. The cost of remediation typically exceeds the fee savings from choosing a cheaper adviser.
Not Verifying the EA Credential Before Engaging
An IRS Enrolled Agent credential is verifiable in under five minutes using the IRS’s online tool. Many clients engage advisers without verifying their credentials, relying instead on the adviser’s website, testimonials, or marketing materials. An adviser who claims to be an EA without holding the credential is misrepresenting their qualifications. Verify before engaging.
Assuming a UK Accountant Can Prepare a Streamlined Submission
A UK accountant without IRS Enrolled Agent or CPA status cannot legally sign a US federal return as a paid preparer and cannot represent a client before the IRS. A UK accountant who offers to prepare a Streamlined submission using their UK credentials is not operating within their permitted scope. The submission may be technically filed, but if it is examined, the adviser cannot represent the client, and the client has no recourse through the professional body’s disciplinary process for US tax errors.
Not Asking About the Annual Compliance Program Before Engaging
The Streamlined submission resolves historical non-compliance. It does not establish an annual program to prevent new non-compliance. A client who engages a Streamlined specialist without discussing the annual program may find that the specialist does not offer ongoing compliance services — or that the annual fee is significantly higher than expected. Establish the annual scope and fee before committing to the Streamlined engagement.
The IRS directory of credentialled tax professionals is published at:
https://irs.treasury.gov/rpo/rpo.jsf
How Jungle Tax Can Help
Jungle Tax is a specialist US-UK cross-border tax advisory firm whose team includes IRS Enrolled Agents and UK-qualified tax practitioners with specific experience preparing IRS Streamlined Filing Experts-level submissions for Americans living in the UK. Every Streamlined submission we prepare includes: a full PFIC and Form 8621 assessment before the returns are prepared; FBAR peak balance calculations using monthly statements for every account; a non-wilfulness narrative drafted specifically for the client’s facts — not a generic template; FTC optimisation using accurate UK income tax figures from the self-assessment or PAYE records; and a written engagement letter specifying the complete scope before any work begins. We verify every client’s willfulness position before certifying the submission. We establish the annual compliance program before the submission closes, so the client is never non-compliant again. You can find further information on our page at https://www.jungletax.co.uk/, or read our guide to IRS Streamlined Filing Compliance vs. Voluntary Disclosure — choosing the right route. Contact our team at hello@jungletax.co.uk or call 0333-8807974 today.
Conclusion
Hiring the right IRS Streamlined Filing Experts is the single most important decision in a Streamlined submission. An incomplete or inaccurately prepared submission does not qualify for the penalty waiver, and the cost of remediation typically exceeds the fee savings from choosing a cheaper or less qualified adviser.
Three points matter most. First, verify the EA or CPA credential independently — using the IRS’s online tool — before engaging any adviser. A UK accountant without US credentials cannot prepare a Streamlined submission correctly. Second, ask the four assessment questions before engaging: UK self-assessment coverage, Form 8621 knowledge, FBAR peak balance approach, and non-wilfulness assessment process. The answers reveal the adviser’s actual qualification level. Third, obtain a written engagement letter with a fixed fee and a complete scope of work before paying any deposit. Verbal estimates and incomplete scopes are red flags.
Speak to a Jungle Tax adviser today — contact us at hello@jungletax.co.uk or visit our https://www.jungletax.co.uk/ to discuss your Streamlined submission.
