UK businesses sending large international transfers must provide source-of-funds documentation under Money Laundering Regulations 2017 and supporting anti-money-laundering checks. The documentation typically required: incorporation evidence, beneficial ownership, ID verification of directors, and clear evidence of where the funds being transferred came from — trading revenue, equity raise, retained earnings, asset sale, or loan. Get this wrong and the transfer is delayed; get it right first time and a £500,000 transfer can settle within hours of instruction. This guide explains what UK businesses actually need to provide in 2026, why specialist brokers ask for it, and how to prepare the documentation pack so transfers move smoothly.
For related Business FX content, see our companion guides on are currency brokers safe, safeguarded client funds, how to set an FX policy for your UK business, and multi-currency receiving accounts.
Why AML and Source-of-Funds Checks Exist
UK Money Laundering, Terrorist Financing and Transfer of Funds (Information on the Payer) Regulations 2017 require all UK financial institutions — including FCA-authorised payment institutions and the specialist currency brokers operating through them — to verify the identity of customers and the legitimate source of the funds being moved. The regime is risk-based: small transactions on long-established accounts attract minimal friction, while large transfers, new customers, or unusual patterns trigger enhanced due diligence.
For UK businesses making international transfers, the practical impact is that any new specialist broker relationship will involve onboarding documentation, and any large transfer (typically above £10,000–£50,000 depending on context) will involve source-of-funds documentation. Both processes are well-established and routine — the friction comes when documentation is incomplete or inconsistent, not when the system is working as intended.
Anthony Bull, CEO of Cambridge Currencies, notes that the businesses with the smoothest large-transfer experience are those who treat AML documentation as a normal part of treasury operations rather than an interruption. The first transfer with a new broker takes longer because the relationship is being established; subsequent transfers move quickly because the documentation pack is already in place.
The Two Stages: Onboarding and Transaction-Level Checks
UK AML obligations on a business currency broker relationship operate at two distinct stages.
Stage 1: Customer Due Diligence (CDD) at Onboarding
When a UK business opens an account with a specialist currency broker, the broker (acting through its FCA-authorised payment partner) is required to perform Customer Due Diligence. This involves verifying the identity of the legal entity, identifying beneficial owners (typically anyone with 25%+ ownership), and assessing the risk profile of the relationship.
For a UK limited company, the onboarding pack typically includes:
- Companies House registration documents (certificate of incorporation, current officers list, current shareholders list).
- Articles of association.
- Confirmation statement (most recent).
- Annual accounts (most recent filed).
- Beneficial ownership disclosure — names, addresses, dates of birth of anyone with 25%+ ownership.
- ID verification of directors and beneficial owners (passport or driving licence).
- Address verification for directors and beneficial owners (utility bill or bank statement, typically dated within 3 months).
- Description of the business activity and expected transfer patterns (currencies, frequency, typical sizes, source markets).
For a UK LLP, sole trader or partnership, the documentation set adjusts but the principles are the same: verify the legal entity, verify the people behind it, understand the business model.
Stage 2: Transaction-Level Source of Funds (SoF)
Once the business is onboarded, individual large transfers may trigger source-of-funds verification. The threshold varies by broker, currency pair, transfer size and the broker’s risk model, but for most UK SMEs the trigger sits around £10,000–£50,000 for routine commercial flows and lower for first transfers or unusual patterns.
Source of funds is exactly what it sounds like: documented evidence that the money you’re sending came from a legitimate, identifiable source. The broker isn’t questioning your business; they’re fulfilling their statutory obligation to verify the funds.
The Six Source-of-Funds Categories UK Businesses Encounter Most
Almost every UK business large transfer falls into one of six SoF categories. Knowing which one applies upfront makes the documentation request straightforward.
1. Trading Revenue
The funds came from normal business activity — customer payments for goods or services. Documentation typically required:
- Recent management accounts or annual accounts showing trading revenue.
- Bank statements showing customer payments accumulating over the period the funds were earned.
- For specific large customer payments, the underlying invoice or contract.
This is the most common SoF category and the easiest to evidence — most UK SMEs have all of this in their accounting platform already.
2. Retained Earnings / Reserves
The funds came from accumulated profit retained on the balance sheet over multiple years. Documentation:
- Annual accounts showing the retained earnings balance.
- A short narrative explaining how the reserves were built up over the relevant years.
3. Equity Raise / Investment
The funds came from a recent share issue, founder investment, or third-party investment. Documentation:
- Companies House filings (SH01 for share allotments, statement of capital).
- Subscription agreement or shareholder agreement evidencing the investment.
- Bank statements showing the investment funds arriving.
- For institutional or VC investment, the term sheet or investment agreement (redacted as needed).
4. Bank Loan or Credit Facility
The funds came from a regulated UK lender. Documentation:
- The loan agreement or facility letter from the bank.
- Bank statements showing the loan funds drawn down.
Lender-sourced funds are typically the easiest SoF to verify because the lender has already done its own due diligence on the business.
5. Asset Sale
The funds came from selling a business asset — property, equipment, a subsidiary, intellectual property. Documentation:
- The sale agreement or contract.
- Completion statement showing the net proceeds.
- Bank statements showing the sale proceeds arriving.
- For property, the solicitor’s completion letter.
6. Director Loan / Shareholder Funds
The funds came from a director or shareholder injecting personal funds into the business. Documentation:
- The loan agreement or board resolution recording the director loan.
- The director’s personal source of funds (since the question now extends to where the director’s personal funds came from — typically salary, dividends, or asset sale).
- Bank statements showing the funds moving from the director’s personal account to the business account.
Director loans get more scrutiny than other SoF categories because they introduce a personal-account leg into the chain.
A Practical Documentation Checklist for a £500k Business Transfer
To make this concrete, here’s the documentation a typical UK SME would prepare for a £500,000 first transfer with a new specialist currency broker.
Onboarding Pack (One-Time)
- Certificate of incorporation.
- Most recent confirmation statement from Companies House.
- Most recent filed annual accounts.
- Articles of association.
- Beneficial ownership disclosure with names, addresses, DOBs of 25%+ owners.
- ID for each director and 25%+ owner: passport or driving licence (clear scan).
- Address proof for each director and 25%+ owner: utility bill or bank statement dated within 3 months.
- Brief description of the business and expected transfer flows.
Transaction Pack (For This Specific Transfer)
- Source-of-funds category identified (e.g. “trading revenue”).
- Supporting evidence: most recent bank statement showing the £500,000 in the business account, with cumulative trading receipts visible over the relevant period.
- Where applicable, the underlying commercial documentation (contract, completion statement, invoice).
- Beneficiary details for the receiving account, verified verbally before sending.
- Reason for the transfer (e.g. “property purchase deposit,” “supplier payment,” “intragroup loan”).
Prepared properly, the entire pack typically fits in a single email or secure portal upload. The broker’s compliance team reviews it, and if the pack is clean, the transfer proceeds without further question. If something is missing or inconsistent, the broker will come back with specific follow-up questions — not as suspicion, but as required compliance.
Why Specialist Brokers Ask for This vs Why Banks Do It Differently
Both UK high-street banks and specialist currency brokers operate under the same Money Laundering Regulations 2017. The difference is in how they apply them.
UK high-street banks tend to apply AML processes through automated screening systems, with friction surfacing as transfer holds, payment delays, or relationship-management calls. The processes are robust but impersonal — the customer often doesn’t know exactly what triggered the review or what specific documentation would resolve it.
Specialist currency brokers tend to apply AML processes through dedicated compliance teams who work directly with named relationship managers. The friction is more visible at onboarding (the documentation pack is requested upfront and explicitly), but in exchange the transaction-level experience is smoother because the relationship is established. Cambridge Currencies works exclusively with FCA-authorised payment partners (Currencycloud FRN 900199 and ScioPay FRN 927951), and the AML process operates through them. See our guide on are currency brokers safe for the full regulatory framework.
When Enhanced Due Diligence Applies
Enhanced Due Diligence (EDD) is a more detailed level of AML verification triggered by specific risk factors. Common UK business triggers:
- Transfers to or from high-risk jurisdictions (those flagged by the Financial Action Task Force or HM Treasury).
- Politically Exposed Persons (PEPs) in the ownership structure — directors or beneficial owners who are or have recently been in prominent public functions.
- Complex ownership structures with multiple corporate layers, particularly across multiple jurisdictions.
- Cash-intensive businesses where source of funds is harder to trace through normal banking records.
- Unusual transfer patterns that don’t match the business profile recorded at onboarding.
EDD typically involves additional documentation, sometimes a phone call to discuss the business and transfer purpose, and occasionally engagement with the broker’s compliance team. None of this is unusual or adversarial — it’s the regulatory framework working as designed.
Common Mistakes UK Businesses Make
Treating AML requests as adversarial. Compliance teams aren’t questioning whether your business is legitimate. They’re fulfilling a statutory obligation. The faster you provide the documentation, the faster the transfer settles.
Sending incomplete packs. An onboarding pack missing one document creates a back-and-forth that adds days. Send everything in one go, even if it feels like over-documentation.
Inconsistent documentation. If the address on a director’s ID doesn’t match the address on the proof-of-address utility bill, the verification fails. Check for consistency before submitting.
Stale documents. Address proofs older than 3 months, accounts more than 12 months out of date, or expired ID documents all fail verification. Refresh before submitting.
Vague source-of-funds explanations. “Business savings” isn’t a source-of-funds answer. “Cumulative trading revenue from EU and US customers over the last 18 months” is. Specificity speeds verification.
Splitting transfers to avoid SoF requests. The Money Laundering Regulations specifically address “structuring” — deliberately splitting transfers to stay below thresholds. This is illegal and triggers enhanced reporting. Always send the full transfer, with full documentation.
Verbal-only beneficiary confirmation skipped. Email-supplied bank details are the largest single class of payment fraud. Always confirm beneficiary details verbally with your specialist before sending funds, especially on first transfers and large amounts.
Timeline Expectations
For a UK SME with a clean documentation pack:
- Onboarding: typically 2–5 working days from submission to approval, assuming the pack is complete on first submission. Specialist brokers often turn this around faster than banks because the named compliance team can prioritise.
- First transfer with SoF: typically same day to 1 working day from documentation submission, assuming the transfer is in line with the onboarding profile.
- Subsequent transfers: routine commercial flows within profile typically execute on the same day they’re instructed, with no further SoF documentation unless the size or pattern is unusual.
The first transfer always takes longest because the relationship is being established. The cumulative time saved across the next 50 transfers is what makes the upfront documentation discipline worthwhile.
Frequently Asked Questions
What is source of funds for a UK business transfer?
Documented evidence that the money being transferred came from a legitimate, identifiable source — typically trading revenue, retained earnings, an equity raise, a bank loan, an asset sale, or a director loan. UK financial institutions are required to verify source of funds on large transfers under Money Laundering Regulations 2017.
What documentation does a UK business need for AML onboarding with a currency broker?
Typically: certificate of incorporation, recent confirmation statement, recent annual accounts, articles of association, beneficial ownership disclosure for 25%+ owners, ID and address proof for directors and beneficial owners, and a description of the business and expected transfer flows.
At what transfer size do source-of-funds checks apply?
The threshold varies by broker, currency pair and risk model, but for most UK SMEs the trigger sits around £10,000–£50,000 for routine commercial flows. First transfers and unusual patterns can trigger SoF at lower amounts. Once a relationship is established and consistent transfer patterns are recorded, routine within-profile transfers typically don’t require additional SoF documentation.
Why are AML checks the same at brokers and banks?
Both UK high-street banks and FCA-authorised payment institutions (which specialist brokers operate through) are subject to the same Money Laundering Regulations 2017. The statutory obligations are identical. The difference is in how the processes are applied operationally — banks tend to use automated screening with friction at the transaction stage, while specialist brokers tend to do more upfront onboarding documentation with smoother subsequent transfers.
Can I split a transfer to avoid AML checks?
No — this is called structuring and is specifically prohibited under UK Money Laundering Regulations. Structuring triggers enhanced reporting to the National Crime Agency and creates significantly more friction than simply providing the source-of-funds documentation for the full transfer. Always send the full amount with full documentation.
How long does AML onboarding take?
For a UK SME with a clean documentation pack, onboarding typically takes 2–5 working days from submission to approval. Pack completeness is the biggest factor — incomplete first submissions add days of back-and-forth.
What is Enhanced Due Diligence?
A more detailed level of AML verification triggered by specific risk factors — transfers to or from high-risk jurisdictions, Politically Exposed Persons in the ownership structure, complex multi-jurisdiction structures, cash-intensive businesses, or unusual transfer patterns. EDD typically involves additional documentation and sometimes a phone discussion with the broker’s compliance team.
Are AML checks adversarial or routine?
Routine. Compliance teams aren’t questioning whether your business is legitimate — they’re fulfilling a statutory obligation under UK Money Laundering Regulations 2017. The faster and more completely you provide the requested documentation, the faster the transfer settles. Treat AML documentation as a normal part of treasury operations rather than an interruption.
Setting up a new specialist currency broker relationship for your UK business and want to make sure your AML and source-of-funds documentation is right first time? Speak to a Cambridge Currencies specialist by phone — we’ll walk you through the onboarding pack, the source-of-funds expectations for your typical transfer flows, and how to make subsequent transfers move smoothly. Request a free quote today. All transfers are completed by phone with a dedicated specialist. We work exclusively with FCA-authorised payment partners.
This guide is for informational purposes only and does not constitute legal, tax or compliance advice. UK Money Laundering Regulations and supporting guidance change. Always seek independent professional guidance from a qualified UK compliance specialist or solicitor for specific scenarios. The Money Laundering Regulations 2017 referenced are the principal UK statutory framework, supported by Financial Conduct Authority guidance and HM Treasury sanctions notices.
