Balance Sheet Forecasting
Executive Summary
Key Takeaways
- ✓ A bank's balance sheet forecast should be built from segmented asset and liability volumes, each with its own growth, repayment, and repricing assumptions, then reconciled through an explicit funding plan.
- ✓ The funding plan should close any gap between forecast asset growth and forecast deposit growth through a named wholesale funding assumption, not left as an unexplained balancing plug.
- ✓ The balance sheet forecast should be checked against capital adequacy constraints, since asset growth consumes risk-weighted capital capacity that may not always be available to support it.
- ✓ The balance sheet forecast should also be checked against liquidity constraints (the loan-to-deposit ratio and, where applicable, regulatory liquidity metrics), since asset growth funded by an unsustainable wholesale funding assumption is not a genuinely achievable forecast.
- ✓ Balance sheet forecasting should connect directly to the interest income build, loan portfolio, and deposit modelling modules already in the model, not be built as a separate, disconnected schedule.
Objective¶
This guide covers how to forecast a bank's balance sheet, within the Banking Financial Modelling pillar, as the central forward-looking exercise the rest of the model is built on — extending the segment-level detail in Loan Portfolio Modelling and Deposit Modelling into a full, reconciled forecast.
Structuring the Forecast¶
The forecast should carry forward the segment-level volume, repayment, and repricing assumptions from the loan portfolio and deposit modelling modules, projecting each segment's balance period by period rather than applying a single blended growth rate to total assets or liabilities.
The Funding Plan¶
Forecast asset growth and forecast deposit growth rarely match exactly. The funding plan is the schedule that explicitly closes this gap: where forecast loan growth exceeds forecast deposit growth, the plan should name the wholesale funding source (interbank borrowing, bond issuance, other wholesale funding) assumed to fund the difference, at an explicit assumed cost. Leaving this gap as an unexplained balancing plug — a "cash" or "other" line that silently absorbs the difference — hides a funding assumption that should be an explicit, reviewable part of the forecast.
Funding Gap = Forecast Asset Growth − Forecast Deposit Growth
Funding Plan = Named Wholesale Funding Source(s) × Assumed Cost, sized to close the Funding Gap
Checking the Forecast Against Capital Adequacy¶
Asset growth consumes risk-weighted capital capacity. The balance sheet forecast should be checked against the resulting risk-weighted assets and capital ratios — see Capital Adequacy Models — rather than produced independently and reconciled to capital constraints only afterward, if at all.
Checking the Forecast Against Liquidity Constraints¶
The forecast should also be tracked against the resulting loan-to-deposit ratio and, where the institution is subject to them, regulatory liquidity metrics. A forecast that assumes unlimited wholesale funding availability at a constant cost, without regard to these constraints, is not a genuinely achievable growth scenario.
Common Construction Pitfalls¶
- Forecasting total asset and liability growth with a single blended rate, losing the segment-level detail needed for a credible forecast.
- Leaving the gap between asset and deposit growth as an unexplained balancing plug rather than an explicit, named funding plan.
- Forecasting balance sheet growth without checking the resulting capital ratios or liquidity metrics.
- Building the balance sheet forecast as a standalone schedule disconnected from the loan portfolio and deposit modelling modules already in the model.
Continue Reading¶
Prerequisites¶
- Banking Financial Modelling — the parent pillar
- Loan Portfolio Modelling
- Deposit Modelling
Related Technical Guides¶
Related Glossary¶
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Frequently Asked Questions
What is balance sheet forecasting in a bank model?
The central forward-looking exercise of projecting segmented asset volumes (loans, securities) and liability volumes (deposits, wholesale funding) period by period, then reconciling the two through an explicit funding plan — the foundation every other bank model output is derived from.
What is a funding plan, and why is it needed?
An explicit schedule closing any gap between forecast asset growth and forecast deposit growth through a named wholesale funding assumption (interbank borrowing, bond issuance, or other wholesale sources), rather than leaving the gap as an unexplained balancing plug that obscures how the growth would actually be funded.
How should the balance sheet forecast be checked against capital adequacy?
By calculating the risk-weighted assets the forecast growth would generate and confirming the resulting capital ratios remain above required minimums and buffers, since asset growth consumes capital capacity that is not unlimited — see Capital Adequacy Models.
How should the balance sheet forecast be checked against liquidity constraints?
By tracking the resulting loan-to-deposit ratio and, where the bank is subject to them, regulatory liquidity metrics, since asset growth funded by an unsustainable or unavailable wholesale funding assumption is not a genuinely achievable forecast.
How does balance sheet forecasting connect to loan portfolio and deposit modelling?
It should draw directly on the segment-level volume, repayment, and repricing assumptions already built in those modules, rather than maintaining a separate, potentially inconsistent set of balance sheet growth assumptions.
Is balance sheet forecasting the same as balance sheet forecasting in a corporate model?
No — a corporate model typically derives the balance sheet from a revenue forecast; a bank model forecasts the balance sheet directly as the primary driver, with the income statement derived from it, reflecting the balance-sheet-first architecture described in Banking Business Model.
Related Articles
Banking Financial Modelling
Banking financial modelling is structurally distinct from a standard corporate model: it is built balance-sheet-first, with earnings derived from asset and liability volumes and spreads rather than a top-line revenue forecast, and it must represent loan portfolio and deposit dynamics, credit loss provisioning, and a set of bank-specific KPIs that a generic corporate model has no equivalent for. This page is the hub for the Knowledge Centre's banking modelling content: how the bank business model translates into a model's architecture, how the three financial statements are structured for a bank, how interest income and the net interest margin bridge are built, and how loan portfolios, deposits, and credit loss provisions should be modelled.
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.
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.
Capital Adequacy Models
Capital adequacy modelling represents the constraint regulatory capital requirements place on how much risk-weighted balance sheet a bank can carry against its available capital base. This guide covers how to structure a capital adequacy model — the capital tiers, the risk-weighted asset base they are measured against, minimum ratio and buffer requirements — and how it should be built as a live check against the balance sheet forecast rather than a standalone reporting exercise calculated after the forecast is already complete.
Loan-to-Deposit Ratio
The loan-to-deposit ratio compares total loans to total deposits, giving a core indicator of how much of a bank's lending is funded from its deposit base versus wholesale or other funding sources. A ratio above 100% means the bank is lending more than it holds in deposits, funding the difference through wholesale markets — a funding structure that carries more refinancing and liquidity risk than deposit-funded lending.
Bank Financial Statements
A bank's three financial statements carry a different structure and internal logic from a standard corporate three-statement model. The balance sheet is the primary earnings driver rather than a supporting schedule; the income statement separates net interest income from fee and other income and shows loan loss provisions as their own distinct line ahead of non-interest expense; and the cash flow statement requires bank-specific adjustments that a corporate model's indirect method does not anticipate. This guide sets out each statement's bank-specific structure and how the three connect.