Source of funds for a crypto off-ramp is the evidence that stablecoins being converted into bank money came from a lawful activity matching the business's declared one. Providers ask when risk rises: a higher-risk profile, an unusual payout, a change in the business. The usual proof pairs an invoice or contract with the blockchain payment that settled it.
This guide covers businesses that send payouts through a provider. It does not describe documentation for individuals. It covers why an off-ramp asks, what triggers a request, which documents pass and what to prepare first.
What is source of funds, and how is it different from source of wealth?
Source of funds is where the specific money moving through the provider came from: operating revenue, a customer payment, a capital contribution. Source of wealth is how the company or its owners built their overall wealth: years of earnings, a prior sale, long-term investments.
Source of funds and source of wealth compared
Source of funds | Source of wealth | |
Question | Where did this money come from? | How did the business or its owners accumulate their assets? |
Typical evidence | Invoices, contracts, bank or exchange statements, blockchain history | Financial statements, tax returns, records of a company sale |
Usually asked | Large or unusual payouts, limit increases | Enhanced due diligence, complex ownership |
A provider can ask for both, at onboarding or later. At Lumx, a business declares its primary source of funds in the onboarding questionnaire, as one value from a fixed list. When several apply, the docs say to pick the main one, and compliance may still ask for evidence.
Why regulators push off-ramps to ask
An off-ramp is where a blockchain balance becomes a bank deposit, so it is where a provider and its banking partners have to vouch for the money.
In the EU, the European Banking Authority's amended ML/TF risk factor guidelines apply from December 30, 2024. They tell crypto-asset service providers to obtain evidence about the source of funds, source of wealth or source of crypto-assets for higher-risk transactions, and they list a customer who stays silent or misleading about it as a risk factor (EBA/GL/2024/01, read November 1, 2026).
In the US, the FinCEN customer due diligence rule asks covered institutions to understand the nature and purpose of each customer relationship, build a risk profile, identify anyone who owns 25 percent or more of a company customer and keep monitoring (FinCEN CDD final rule, read November 1, 2026). FATF Recommendation 10 (customer due diligence) and Recommendation 15 (virtual assets) are the global base for both.
Every stablecoin has a public history, so a provider can see a deposit that passed through a sanctioned address, even when your client acted in good faith. Monitoring is covered in stablecoin AML compliance for fintechs.
At Lumx, KYC (know your customer, the verification of an individual) runs through Sumsub and KYT (know your transaction, the monitoring of payments and wallets) through Chainalysis.
When an off-ramp asks for source of funds
The table lists six moments, what the provider sees and what to have ready. Rows 1 to 4 follow the Lumx source of funds page, row 5 follows the transaction limits page and row 6 is common industry practice, not a Lumx rule.
The moments a source of funds request is raised, and the paper that answers each
Trigger | What the provider sees | Have ready |
Enhanced due diligence tier at onboarding | A country, industry or risk score that calls for a deeper review | Proof of the declared primary source of funds, ownership chart |
High volumes or complex funding | Flows that need validation, or funding that runs through several entities | Contracts and invoices behind the flows, a map of the entities and wallets involved |
Material change | New owners, a new business model, or expected activity that moved | Updated corporate documents and a new statement of expected volume |
Regulatory obligation | A rule that requires the evidence regardless of the profile | Whatever the request lists |
Limit increase | A supporting document that does not justify the amount requested | Bank statement, financial statements or tax return that supports the monthly volume |
A flagged payout | Monitoring holds one transfer, or its blockchain history looks unusual | For a Lumx transaction RFI: the relationship between sender and receiver, the purpose and the expected outcome. Separately, as our advice: the trail from the source |
The customer is told through an RFI (request for information, a compliance hold that asks for a document before a transaction clears) that names the documents. The limit row follows the transaction limits page: a limit increase request needs a supporting document, which compliance reviews with a target of 1 business day. Default limits for a business at KYB (know your business, the verification of a company and its owners) Standard are $50,000 per transaction and $100,000 per day and per month.
Documents that pass, by the source you declared
The strongest evidence matches the source of funds you declared at onboarding, and a mismatch between the two invites a second request. The Lumx source of funds page lists generic evidence categories and the onboarding fields page lists the codes. The table pairs the two by our reading: the middle column is the docs category in the docs' own words, the right column in italics is our advice, not a published rule.
Declared source of funds (business customers): the docs category, and the evidence we would prepare (our reading, not a published rule)
Declared value | Docs category | Evidence we would prepare |
| Revenue documentation: invoices, customer contracts, settlement statements or receipts demonstrating operating income | Invoices and contracts for the period, with settlement statements or receipts |
| Investment or capital contribution records: subscription agreements, capital injections, founder contribution confirmations | Subscription agreements or founder contribution records |
| Loan or financing agreements showing lawful borrowing | The executed loan agreement or credit facility |
| Asset sale records: proceeds from the sale of business assets, securities or property | The sale record and proof the proceeds arrived |
| No dedicated category; the nearest are bank statements and asset sale records | Statements from the regulated institution or exchange that holds the investments, with the sale records |
| Crypto categories: wallet ownership evidence, transaction history with hashes, exchange account statements | Hashes and addresses together with exchange statements and proof of control of the sending wallets |
| No dedicated category | The intercompany agreement and the sending company's bank statement |
Every document, per the docs, is issued in the name of the business or the relevant funding entity, shows the source and flow of funds, is legible and complete with no material redactions, and is a PDF, JPG or PNG.
How do you prove source of funds when the money arrived as USDC?
Tell the story of the money, then attach the receipts. Take an invented case: a Brazilian distributor pays a Mexican supplier. It bought USDC on a regulated exchange with reais from its own bank account, withdrew the USDC to a wallet it controls and sent it to be paid out in Mexican pesos over SPEI (Mexico's interbank transfer system, run by Banxico). The provider asks about the payout. The evidence pack has five parts.
The reason for the payment: the supplier's invoice and the purchase contract.
The funding of the stablecoins: the company's bank statement showing the reais that left, and the exchange statement showing the USDC purchase.
The movement: the exchange withdrawal, with its transaction hash, the two wallet addresses, the amount and the date.
Control: cryptographic proof that the company controls the wallet the funds moved from.
Anything in between: if the USDC was swapped or bridged before the payout, the hashes for those steps too.
Step 5 is where packs break: hops through several wallets with no explanation look like layering to wallet screening.
The Lumx docs ask that the documents show where funds come from, how they were generated and how they will move to Lumx. For a payout from a custodial wallet, that last link is the transfer into the wallet, so keep its hash with the pack. A USDC to BRL conversion for a Pix (Brazil's instant payment system) payout follows the same logic.
What makes a review stall, and what happens while it is open
Reviews usually stall on paperwork, not on the money. These trigger a second question:
The funds do not match the declared activity.
A third-party wallet paid with no contract or explanation.
Statements with heavy redactions, or only the first page of a multi-page document.
Names that differ between the documents and the onboarding submission.
Blockchain exposure to mixers or sanctioned addresses.
While a request is open, the affected object waits. For a customer, the Lumx docs say the customer moves to RFI and the customer.rfi webhook fires; on resubmission the customer returns to UNDER_VERIFICATION and the review runs again.
A held on-ramp or off-ramp is a separate case: a transaction RFI. Compliance writes on your usual email or Slack channel and, per the docs, usually asks for the relationship between sender and receiver, the purpose, the expected outcome and any other context. A transaction left unanswered for 24 hours may be refunded to the sender, and that window applies to every transaction. A limit-increase request is not a transaction RFI, unless approving a transaction depends on it.
How long does a source of funds review take? It depends on the documents and on how fast the answers come back. The one target Lumx states is 1 business day for reviewing limit-increase documents.
A source of funds request asks for a document and does not refuse. Outright refusals, including FINAL_REJECTION, are in why a stablecoin payout gets rejected.
Who collects the documents, and a checklist before the first request
If your business sends payouts for its own customers, the provider talks to you and you talk to your customers, so collection becomes a job in your product. The provider verifies and reviews. You collect the evidence, upload it and answer on time. Write that split down, and ask the provider in writing for its accepted documents and deadline.
At Lumx, the RFI reaches you through a webhook for customers and through your email or Slack channel for held transactions, so the person with the documents must be reachable on both. An RFI API is planned for accounts by the end of 2026 and for transactions between the end of 2026 and the first quarter of 2027. The onboarding side is in designing a KYB onboarding flow, and the identity side in what KYB is.
Do this before the first large payout:
Declare the primary source of funds that is true, and keep its proof in one folder.
Keep the ownership chart, the corporate documents and a recent, complete bank statement beside it. That is our advice.
Keep the contract and invoices that explain each counterparty's payments.
For crypto-origin funds, keep hashes, addresses, exchange statements and proof that you control the sending wallets.
Name the person who answers, with access to finance and legal records.
I would build this folder per customer, before the first large payout, and not per payment after the first hold. The reply to a source of funds request is a finance document that happens to arrive through an API, so I would give it a named owner in finance or compliance, not whoever happens to be on call for the integration. Before signing with any provider, I would ask which of its triggers are written down and which are decided case by case, because the answer tells you how much of your preparation has to be general.
When fighting a source of funds request is the wrong move
Sometimes the paper does not exist. A fluent reply will not help a customer who cannot show where the money came from, and documents that nearly fit turn a clarification into a final decision.
A payout refused at the API before a transaction exists is not a source of funds request, and a limit that is too low calls for a limit increase request with its own document.
How source of funds plays out on a Lumx payout
Lumx is stablecoin payments infrastructure for businesses that move money between Latin America and the rest of the world: one API to collect, hold, convert, and pay out in BRL, MXN, COP, USD, EUR, and GBP or in USDC and USDT, over local rails such as PIX, SPEI, PSE, Bre-B, ACH, FEDWIRE, SEPA, and Faster Payments, with SWIFT and on-behalf-of payments and collections (POBO and COBO) in USD, EUR, and GBP, plus named virtual accounts, custodial wallets, and KYB/KYC built in.
Source of funds enters at two points. At onboarding, a business customer's transactional information covers the source of funds, monthly revenue, expected volume and counterparties. Later, an RFI lists the documents compliance needs, in the cases from the triggers table.
On a payout, the business customer is verified first, then the conversion and payout run over the rail the destination uses. The live rails are on the coverage page, countries on the supported countries page, limits by rail in limits and cut-offs, and the end-to-end flow is in global payments. If monitoring holds a transfer, compliance writes on your usual channel and the 24-hour window applies.
Methodology and sources
Lumx product facts come from the docs read on November 1, 2026: Source of Funds and Wealth, Request for Information, Transaction Limits, Identity Verification, Onboarding Fields, Document Types and Supported countries. The EBA guidelines and the FinCEN rule were read in full text the same day. The FATF recommendations are linked to the FATF page, which blocked automated requests, so they were not re-read. The worked example is invented and uses no client data.
Verified on November 1, 2026. Operational context, not legal, tax, or investment advice.
Cover photo: Sean Mungur on Unsplash.
What source of funds does a crypto off-ramp ask for?
A crypto off-ramp asks for proof that the stablecoins you convert came from a lawful activity that fits your business: an invoice or contract, a bank or exchange statement and, for crypto-origin funds, transaction hashes and wallet addresses. Documents must be in the business's name and complete. With Lumx, the RFI lists the specific documents, and the accepted categories are on the Source of Funds and Wealth page of the docs.
What is the difference between source of funds and source of wealth?
Source of funds is the origin of the specific money moving through the provider, such as operating revenue or a customer payment. Source of wealth is how the business or its owners built their total assets over time. With Lumx, the docs say either can be requested at onboarding or in an ongoing review, and the customer declares a primary source of funds in the onboarding questionnaire.
When does an off-ramp ask for source of funds?
Typical moments are an enhanced due diligence tier, high volumes or complex funding, a material change, a regulatory requirement, a limit increase and a flagged payout. With Lumx, the docs list the first four as the cases where compliance asks, through an RFI that names the documents.
How do I prove the source of USDC I received?
Pair the commercial document with the blockchain trail: the invoice or contract, then the transaction hash with both wallet addresses, the amount and the date. Add exchange statements and proof that you control the sending wallet. Include every swap or bridge step so the trail has no gap. With Lumx, the docs accept wallet ownership evidence, blockchain transaction history and exchange statements for crypto-origin funds.
What happens if I do not answer a source of funds request?
It depends on what is waiting. A customer in an enhanced due diligence request stays paused until you resubmit. A held transaction is different: compliance asks for context first, and a transaction left 24 hours without an answer may be refunded to the sender. With Lumx, a customer in RFI waits until you resubmit through the onboarding endpoints, and a held payout waits for your reply on the channel compliance used.
