Loan-to-Deposit Ratio
Executive Summary
Key Takeaways
- ✓ The loan-to-deposit ratio expresses total loans as a percentage of total deposits, a core indicator of how much lending is funded from the deposit base versus wholesale or other funding sources.
- ✓ A ratio above 100% means loans exceed deposits, with the difference funded through wholesale markets — a funding structure that carries more refinancing and liquidity risk than deposit-funded lending.
- ✓ The ratio should be modelled as a live constraint on loan growth, not just a reported output, since loan growth outpacing deposit growth increases reliance on wholesale funding that may not always be available on favourable terms.
- ✓ The appropriate loan-to-deposit level varies by business model and funding market access — a bank with strong, diversified wholesale funding access can sustainably run a higher ratio than one without it.
- ✓ The ratio should be read alongside more granular regulatory liquidity metrics (the liquidity coverage ratio and net stable funding ratio), since it does not itself capture the maturity profile or behavioural stability of either the loan or deposit base.
Definition¶
The loan-to-deposit ratio expresses total loans as a percentage of total deposits, a core indicator of how much of a bank's lending is funded from its deposit base versus wholesale or other funding sources.
Calculation¶
Loan-to-Deposit Ratio = Total Loans ÷ Total Deposits
Interpretation¶
A ratio above 100% means the bank is lending more than it holds in deposits, funding the difference through wholesale markets or other non-deposit sources — a funding structure that generally carries more refinancing and liquidity risk than lending funded entirely by deposits, since wholesale funding is typically less stable and more sensitive to market conditions than a diversified deposit base.
There is no single universally "correct" level for this ratio. The appropriate level varies by business model and funding market access — a bank with strong, diversified wholesale funding access can sustainably operate at a higher ratio than one without it, making the ratio most meaningful assessed against the bank's own funding strategy rather than a fixed benchmark.
Modelling as a Growth Constraint¶
The loan-to-deposit ratio should be built into a model as a live constraint on loan growth, not merely calculated as a reported output after the fact. See Loan Portfolio Modelling — a forecast that grows the loan book faster than the deposit base, without checking the resulting ratio against the bank's funding strategy, presents an unfunded growth scenario as though it were readily achievable.
Relationship to Regulatory Liquidity Metrics¶
The loan-to-deposit ratio is a headline funding-structure indicator, but it does not capture the maturity profile or behavioural stability of either the loan or deposit base — a bank could show an acceptable ratio while still carrying significant liquidity risk from a maturity mismatch the ratio itself does not reveal. It should be read alongside the more granular Liquidity Coverage Ratio and Net Stable Funding Ratio for a complete liquidity risk picture.
Audit Considerations¶
- Confirm the loan-to-deposit ratio is modelled as a live constraint checked against forecast loan and deposit growth, not only reported after the fact.
- Confirm the appropriate benchmark level is assessed against the bank's own funding strategy and market access, not a universal standard.
- Confirm the ratio is read alongside more granular liquidity metrics, not treated as a complete liquidity risk indicator on its own.
Common Errors¶
| Error | Description | Risk |
|---|---|---|
| Growth without constraint check | Loan book forecast to grow faster than deposits with no reconciliation to funding capacity | Presents an unfunded growth scenario as achievable |
| Universal benchmarking | Ratio compared to a fixed "acceptable" level regardless of funding access | Misjudges a bank's actual funding risk |
| Standalone liquidity assessment | Ratio treated as sufficient evidence of liquidity strength on its own | Maturity mismatch risk not captured by this ratio goes undetected |
Continue Reading¶
Prerequisites¶
- Deposit Modelling — the parent guide
- Loan Portfolio Modelling
Related Technical Guides¶
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Frequently Asked Questions
What is the loan-to-deposit ratio?
Total loans expressed as a percentage of total deposits, a core indicator of how much of a bank's lending is funded from its deposit base versus wholesale or other funding sources.
How is the loan-to-deposit ratio calculated?
Loan-to-Deposit Ratio = Total Loans ÷ Total Deposits.
What does a ratio above 100% mean?
That the bank is lending more than it holds in deposits, funding the difference through wholesale markets or other non-deposit funding sources — a structure that carries more refinancing and liquidity risk than lending funded entirely by deposits.
Is there a single "correct" loan-to-deposit ratio?
No — the appropriate level varies by business model and funding market access. A bank with strong, diversified wholesale funding access can sustainably run a higher ratio than one without it, so the ratio is best assessed against the bank's own funding strategy and access, not a universal benchmark.
Why should this ratio be modelled as a constraint, not just reported?
Because loan growth that consistently outpaces deposit growth increases reliance on wholesale funding that may not always be available on favourable terms — a model that forecasts loan growth without checking it against deposit growth risks presenting an unfunded growth scenario as though it were straightforward to achieve.
Does the loan-to-deposit ratio capture liquidity risk fully?
No — it is a headline funding-structure indicator but does not capture the maturity profile or behavioural stability of either the loan or deposit base. It should be read alongside more granular regulatory liquidity metrics — see Liquidity Coverage Ratio and Net Stable Funding Ratio.
Related Articles
Deposit Modelling
Deposit modelling is the liability-side counterpart to loan portfolio modelling: deposits should be segmented by product type — transactional, savings, and term — each carrying its own volume, cost, and behavioural assumptions. Behavioural modelling matters more on the deposit side than almost anywhere else in a bank model, since a deposit's contractual maturity (or lack of one, for transactional accounts) frequently does not match its actual behavioural stickiness, and that gap is central to both funding and liquidity risk management.
Loan Portfolio Modelling
Loan portfolio modelling is the asset-side counterpart to deposit modelling: the loan book should be segmented by product type, risk grade, or business line, each carrying its own origination, repayment, yield, and expected loss assumptions. This guide covers how to structure that segmentation, how to roll forward segment-level balances period over period, and how the segmented output feeds both the interest income build and credit loss provisioning.
Liquidity Coverage Ratio
The liquidity coverage ratio (LCR) tests whether a bank holds enough high-quality liquid assets to survive a defined 30-day acute stress scenario. This guide covers how to model the LCR's two components — the stock of high-quality liquid assets and net cash outflows under the stress scenario — and how the deposit and funding behavioural assumptions built elsewhere in the model feed directly into the outflow calculation.
Net Stable Funding Ratio
The net stable funding ratio (NSFR) tests whether a bank's longer-term assets are backed by a stable enough funding profile over a one-year horizon, complementing the short-term liquidity coverage ratio. This guide covers how to model the NSFR's two components — available stable funding, weighted by the behavioural stability of each funding source, and required stable funding, weighted by the tenor and liquidity of each asset — and how it connects to the balance sheet forecast and deposit modelling already built elsewhere in the model.
Banking KPIs
A bank model should expose a defined set of bank-specific KPIs as explicit model outputs, built directly from the model's own calculations rather than computed ad hoc outside the model for a board pack. This guide sets out the core banking KPI set — profitability metrics (net interest margin, return on assets, return on equity), efficiency (cost-to-income ratio), and asset quality (non-performing loan ratio, provision coverage ratio) — how each should be calculated, and how they should be structured as a dedicated output module rather than scattered across the model.