Source of Funds is the regulatory requirement for iGaming operators to verify, through documentation, that a player's deposits come from legitimate, declarable income.
Source of Funds (SoF)
**TL;DR:** Source of Funds is the regulatory requirement for iGaming operators to verify, through documentation, that a player's deposits come from legitimate, declarable income.
What it means
When a player's deposit or cumulative activity passes a defined threshold — set by regulator or internal AML policy — the operator must request and review SoF evidence. Acceptable documents typically include recent payslips, tax returns, bank statements, sale-of-property documents, or business accounts. The operator's MLRO (Money Laundering Reporting Officer) signs off whether the SoF is plausible relative to the player's spend.
SoF is distinct from Source of Wealth (SoW), which addresses overall financial position rather than the origin of a specific transaction. In practice the two are blended in most operator processes, especially for VIPs.
Formula / How it's measured
Not a metric — a compliance process. Mechanism: thresholds trigger SoF requests (e.g. cumulative deposits >£2,000/30d in UK GC environments, or any single deposit >€2,000 under EU AMLD). Player uploads documents → analyst reviews → MLRO approves, rejects, or escalates → account may be restricted until SoF complete.
Example: a UK casino player deposits £8,000 over 14 days. SoF triggered. Player uploads March payslips showing £3,400/month net + bank statement balance £12,000. MLRO assesses: spend is ~70% of monthly take-home — borderline, additional questions sent → player declines → account restricted, funds returned post-investigation.
Why it matters for operators
SoF failures are the most common source of seven-figure regulator fines in UK, Sweden, and Germany. They are also the primary mechanism by which VIP programmes blow up — high spend without commensurate SoF is the textbook regulator finding.
Common benchmarks (2026)
- UK Gambling Commission thresholds: typically £2,000 deposits/30 days
- Sweden Spelinspektionen: ~SEK 5,000 enhanced checks
- EU AMLD: €2,000 occasional transaction trigger
- Documents accepted: payslips, tax returns, bank statements, property sale, business accounts
- SoF approval workflow time: 24h–14 days
Common mistakes
- Accepting low-quality screenshots without verification
- Failing to suspend deposits while SoF is pending
- VIPs treated leniently — exact opposite of regulator expectation
See also