Source of funds is the origin of the specific money moving into an account or through a transaction, such as a customer payment, a loan or an investor's capital contribution; source of wealth is the origin of a person's or entity's total net worth, such as a business sale, an inheritance or years of salary. Source of funds answers "where did this money come from?" and source of wealth answers "how did this person come to have this much?"
Why it matters in KYB review
Both appear in US due diligence expectations. The FFIEC BSA/AML Examination Manual lists "source of funds and wealth" among the additional information a bank may obtain, based on the customer risk profile, to understand the nature and purpose of the relationship. For private banking accounts for non-US persons, 31 CFR 1010.620 requires reasonable steps to ascertain "the source(s) of funds deposited" and to review activity for consistency with that information. The 2020 interagency statement on PEPs names "known legitimate source(s) of funds" as one factor that can lower a PEP relationship's risk.
In KYB, source of funds usually concerns the business (the expected inbound payments and the capital used to start it). Source of wealth usually concerns the beneficial owners behind it, especially when a small or new company expects large volumes.
What an analyst checks
Source of funds - Expected inbound flows: who pays the business, from which countries, by which rails. - Initial capitalisation: bank statements, investor agreements, loan documents. - Consistency between stated revenue, company age, headcount and projected volume.
Source of wealth - The narrative of how the owner built their wealth, with dates. - Corroboration: company sale announcements, filed accounts, property records, press coverage, prior employment. - Whether the claimed wealth is plausible for the person's age and career.
Common pitfalls
- Using the two terms interchangeably, then collecting the wrong evidence.
- Asking for source of wealth on every low-risk case, which slows onboarding without improving risk decisions.
- Accepting a bank statement as proof of source. It shows where the money sits, not how it was earned.
- Leaving the gap unrecorded. If a claim cannot be corroborated, the file should say so.
Related terms
Enhanced due diligence, politically exposed person, customer due diligence, adverse media screening.
Sweat AI is an AI-native BPO for banks and fintechs, working onboarding and fraud queues. When a case needs source-of-funds or source-of-wealth work, our analysts corroborate the applicant's account against public records and the documents provided, and mark what could not be established. See business investigations.
Questions
Do I need both for every business customer?
No. Most institutions ask for source of funds or wealth on a risk basis, typically for higher-risk customers, PEP relationships and EDD cases. Your policy sets the trigger.
Is a signed declaration enough?
A declaration records the claim. For higher-risk cases analysts look for independent evidence that makes the claim plausible, and record where the evidence stops.
Sources
- 31 CFR 1010.620, Due diligence programs for private banking accounts (eCFR), accessed 2026-09-30
- FFIEC BSA/AML Examination Manual, Customer Due Diligence, accessed 2026-09-30
- Interagency Joint Statement on BSA Due Diligence Requirements for Customers Who May Be Considered PEPs (August 21, 2020), accessed 2026-09-30