Blog · Finance metrics and formulas · Banking
Bank ratios connect profitability, credit quality, funding and capital. Compare a consistent set across two periods, trace the movements to reported amounts and assign the questions to the right owners.
Bank ratios show how earnings, credit quality, funding and capital move together. The useful management question is which reported amounts changed, why they changed and who owns the response. Keep a small set of consistently defined measures beside their underlying balances rather than ranking a bank on one percentage.
Separate measures of a period's activity from measures of a balance at a reporting date. Income belongs to a stated period; loans, deposits and capital are balances. A comparison fails when those boundaries change without explanation.
| Question | Measures to review | Management owner | Follow-up decision |
|---|---|---|---|
| Are earnings covering the asset base? | Return on assets; net interest margin | Finance and treasury | Explain pricing, funding costs and asset mix |
| Is overhead absorbing more revenue? | Efficiency ratio | Finance and operating leaders | Separate revenue pressure from expense growth |
| Is credit performance deteriorating? | Noncurrent loans; net charge-offs; allowance coverage | Credit risk | Identify portfolios requiring review |
| How dependent is lending on deposit funding? | Loans to deposits; funding concentration | Treasury | Review deposit stability and available funding |
| What capacity remains to absorb losses? | Reported CET1, total capital and leverage ratios, as applicable | Capital management | Review capital needs and planned balance-sheet changes |
These are complementary questions. Loans to deposits describes one funding relationship; it does not measure how quickly every asset can become cash. Likewise, a noncurrent-loan ratio describes recorded credit problems, not all future losses.
Use the dedicated explanations of return on assets, net interest margin and loan-to-deposit ratio for their detailed calculations. This review keeps those measures together so their movements can be interpreted jointly.
Start with the bank's reported financial and regulatory schedules. Keep the legal entity, period end, units, ratio definition, numerator, denominator and source reference in the comparison export. Distinguish the insured bank from its holding company; combining their figures creates a comparison neither entity reported.
For earnings ratios, retain the reported average balance and annualization convention. The FFIEC's UBPR FAQ explains that earnings-related ratios annualize income or expense before dividing by an average asset or liability balance. A quarterly income amount divided directly by average assets is therefore not comparable with an annualized reported return.
Do not reconstruct regulatory capital from ordinary book equity. The Federal Reserve's capital definitions define CET1 relative to risk-weighted assets and explain that banks using the community bank leverage ratio framework do not have to report CET1 and risk-weighted assets. A blank under a different framework is not zero capital.
The related bank financial statements page explains the reporting package behind these measures; borrowing-company ratios belong in financial ratios for bank loans.
Consider a hypothetical US commercial bank. Both columns cover a full year, with income amounts for the year and closing balances where labeled. All amounts below are USD; percentages are rounded to two decimal places after calculation.
| Reported input (USD) | 2024 | 2025 |
|---|---|---|
| Interest income | 48,000,000 | 54,000,000 |
| Interest expense | 18,000,000 | 24,000,000 |
| Noninterest income | 10,000,000 | 12,000,000 |
| Noninterest expense | 25,000,000 | 26,800,000 |
| Intangible amortization included in expense | 1,000,000 | 1,000,000 |
| Credit-loss provision | 3,000,000 | 4,000,000 |
| Income tax expense | 3,000,000 | 2,800,000 |
| Average total assets | 900,000,000 | 1,000,000,000 |
| Average earning assets | 800,000,000 | 900,000,000 |
| Closing gross loans | 600,000,000 | 660,000,000 |
| Closing deposits | 750,000,000 | 760,000,000 |
| Closing noncurrent loans | 6,000,000 | 9,900,000 |
| Reported CET1 capital | 75,000,000 | 76,500,000 |
| Reported risk-weighted assets | 600,000,000 | 675,000,000 |
First reconcile the income amounts. Net interest income is interest income less interest expense: $30,000,000 in each year. Net income is that amount plus noninterest income, less noninterest expense, provision and tax: $9,000,000 in 2024 and $8,400,000 in 2025.
For overhead, use the FDIC Quarterly Banking Profile's efficiency-ratio definition: noninterest expense less intangible amortization, divided by net interest income plus noninterest income. Its glossary also defines noncurrent loans as loans past due at least 90 days or in nonaccrual status. Use mutually exclusive reported categories so the same loan is counted once.
Efficiency ratio = (Noninterest expense − Intangible amortization) / (Net interest income + Noninterest income)
| Measure | 2024 calculation | 2025 calculation | Reading |
|---|---|---|---|
| Return on assets | 9,000,000 / 900,000,000 = 1.00% | 8,400,000 / 1,000,000,000 = 0.84% | Earnings fell while average assets grew |
| Net interest margin | 30,000,000 / 800,000,000 = 3.75% | 30,000,000 / 900,000,000 = 3.33% | More earning assets produced unchanged net interest income |
| Efficiency ratio | 24,000,000 / 40,000,000 = 60.00% | 25,800,000 / 42,000,000 = 61.43% | Adjusted overhead took a larger revenue share |
| Noncurrent loans / gross loans | 6,000,000 / 600,000,000 = 1.00% | 9,900,000 / 660,000,000 = 1.50% | Problem balances grew faster than loans |
| Gross loans / deposits | 600,000,000 / 750,000,000 = 80.00% | 660,000,000 / 760,000,000 = 86.84% | Lending grew faster than deposit funding |
| CET1 / risk-weighted assets | 75,000,000 / 600,000,000 = 12.50% | 76,500,000 / 675,000,000 = 11.33% | Risk-weighted assets outgrew CET1 |
The check is multiplication back to the source amount. Before rounding, each ratio multiplied by its denominator must recover its numerator. Also tie net income to the income statement and capital inputs to the regulatory schedule. These checks prove the arithmetic and mapping; they do not establish that a capital level meets every requirement applicable to the bank.
In this example, higher interest income did not improve net interest income because interest expense rose by the same amount. Finance and treasury should explain funding repricing and earning-asset mix before treating the larger balance sheet as progress.
Credit risk should explain the increase in noncurrent loans by portfolio and vintage. Treasury should explain how loan growth was funded. Capital management should reconcile the risk-weighted asset increase to growth, mix and other reported changes. Each owner should supply the underlying movement and the next management action, not a general statement that the ratio changed.
Bring a file of reported ratios with their underlying amounts, periods and definitions. Covirage maps the columns, its tools compute and check the comparisons, and the external AI model explains the results with every figure traced to its rows. Create a free Covirage account and bring a sample of your own data.
See Covirage for commercial banking for the supporting industry context.
Start with profitability, credit quality, funding and capital together. Return on assets and net interest margin describe earnings, while noncurrent loans, loans to deposits and regulatory capital add the risk context. A strong earnings ratio alone does not establish that funding or credit conditions are sound.
Under a consistent definition, a lower efficiency ratio means less operating revenue is absorbed by overhead. Check whether improvement came from sustainable revenue, lower expenses or an unusual gain. Compare the exact adjustments before placing another bank's reported ratio beside yours.
Book equity divided by assets is a balance-sheet measure, but it cannot replace a regulatory capital ratio. Regulatory measures use defined capital amounts, adjustments and specific denominators. Bring the reported capital schedule into the review and preserve the applicable reporting framework.
A ratio can improve because its denominator grows faster than its numerator. For example, problem loans can increase in dollars while their share of total loans falls. Review both amounts and the ratio, and check whether acquisitions or portfolio sales changed the population.