Source of Funds
Direct definition
Source of funds is the documented origin of money used for a down payment, closing costs, or reserves during mortgage underwriting.
Written by the Vabasso Mortgage Editorial Team · Reviewed against agency and federal sources · Read our editorial policy for how we research and review mortgage content
Plain-English explanation
Lenders require borrowers to show where their money came from — such as savings, a gift, sale of an asset, or a retirement account — to confirm funds are legitimate and not an undisclosed loan. Documentation requirements vary by lender and program.
Why it matters
Unexplained large deposits can delay or jeopardize approval, so understanding what documentation is expected helps borrowers prepare.
Where you may see it
- Bank statements
- Gift letters
- Underwriting conditions
A real-world example
Educational and illustrative only
A common misunderstanding
Source of funds review is not intended to question a borrower's finances personally — it is a standard step to verify funds are not undisclosed debt.
Ask Vabasso AI
- Author
- Vabasso Mortgage Editorial Team
- Reviewed by
- Vabasso Mortgage Licensed Advisory Team
- Last reviewed
- July 30, 2026