Bank balance sheet: loan book and funding
Loans by segment, deposits by type, wholesale funding.
By Surojit Chakraverti, founder of L3VLUP and an investor running a long-short healthcare and technology equities strategy.
On this subject: bank balance sheet: loan book and funding.Updated 30 October 2026
What it does
Where a bank model starts, because a bank’s product is its balance sheet. Loans grow by segment, each with its own rate; cash at the central bank and a buffer of liquid securities are held as shares of deposits; deposits grow by type, from current accounts that pay nothing to term deposits that pay close to the market. Wholesale funding closes whatever gap is left, and equity grows by the capital the bank retains. The loan-to-deposit ratio and the share of wholesale funding say how the bank is financed.
Where it lives
The same schedule in each model that carries it, with the rows to open. Open a model in the browser, go to the sheet, and click the lines.
- Assumptions, rows 20–25: Mortgages: gross loans, FY0A, Mortgages: loan growth, base case, Consumer loans and cards: gross loans, FY0A, Consumer loans and cards: loan growth, base case…
- Assumptions, rows 36–41: Cash at the central bank, % of deposits, Investment securities, % of deposits, Securities: repricing beta to the policy rate, Securities: spread over beta x policy rate…
- Assumptions, rows 44–51: Current accounts: balance, FY0A, Current accounts: growth, Savings accounts: balance, FY0A, Savings accounts: growth…
- Balance Sheet, rows 6–15: Mortgages: growth, selected scenario, Mortgages: gross loans, Consumer loans and cards: growth, selected scenario, Consumer loans and cards: gross loans…
- Balance Sheet, rows 18–22: Cash at the central bank, Investment securities, Other assets, Goodwill and intangible assets…
- Balance Sheet, rows 25–38: Current accounts, Savings accounts, Term deposits, Customer deposits…
What a reviewer looks for
- Growing the balance sheet as one line, so the funding mix and its cost cannot change.
- Making cash the plug in a bank, where liquid assets are a requirement rather than a remainder.
- A balance sheet that balances only because one line is defined as the difference, with no check that the flows behind it are complete.
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