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The bank efficiency ratio compares noninterest expense with operating revenue. Work the calculation from income and expense lines, reconcile the totals, and explain a change by cost driver.
The efficiency ratio in banking measures noninterest expense relative to operating revenue, usually net interest income plus noninterest income. It shows how much of that revenue is absorbed by defined overhead, so a lower percentage indicates greater cost efficiency on that basis. Compare the underlying lines and adjustment policies before interpreting a change.
Bank efficiency ratio = Defined noninterest expense / (Net interest income + Defined noninterest income) × 100
Net interest income = Interest income − Interest expense
The FDIC's Quarterly Banking Profile glossary defines its efficiency ratio using noninterest expense less amortization of intangible assets, divided by net interest income plus noninterest income. That is a specific convention, rather than permission to remove any cost management considers unusual.
For the example below, there is no intangible amortization, no securities gain or loss, and no tax-equivalent adjustment. Consequently, reported noninterest expense is also the defined numerator. Interest expense is already reflected in net interest income; credit-loss provision and income tax are outside this ratio.
Cost-to-income describes the same general relationship, but the label alone does not establish identical calculations. A comparison sheet should identify each included account and every adjustment to either side of the fraction. Keep reported and adjusted versions separately labeled.
This is an earnings-efficiency measure. The bank leverage ratio addresses capital adequacy using a different numerator and denominator; an efficiency improvement does not answer that question.
Ask finance for an income-statement export with reporting entity, period start, period end, account, account description, amount, cost center, and adjustment flag. Use positive expense amounts for this worksheet, even if the ledger exports debits and credits with another sign convention.
At branch level, add the supplied internal funding allocation and central-cost allocation rules. A deposit-gathering branch should not be compared with a lending branch before their revenue and funding charges have a consistent basis. The bank-wide ratio should reconcile after internal entries and eliminations.
The FDIC earnings examination manual separates net interest income, noninterest income, noninterest expense, provision expense, and taxes in its analysis. It also recommends examining significant overhead components and whether their sources are recurring. Those distinctions make the ratio explainable.
A fictional US commercial bank compares the quarters ending March 31 and June 30, 2026. All values below are invented inputs, not market benchmarks. Each column contains only that quarter's activity, not cumulative year-to-date amounts.
| Income or expense line | First quarter (USD) | Second quarter (USD) |
|---|---|---|
| Interest income | 9,000,000 | 9,400,000 |
| Interest expense | 3,000,000 | 3,200,000 |
| Noninterest income | 2,000,000 | 1,800,000 |
| Salaries and benefits | 3,000,000 | 3,150,000 |
| Occupancy | 800,000 | 820,000 |
| Technology and processing | 700,000 | 750,000 |
| Other noninterest expense | 500,000 | 580,000 |
First calculate net interest income, then revenue and expenses. Do not divide overhead by gross interest income: that would ignore funding cost and fee revenue.
| Calculation step | First-quarter calculation | Second-quarter calculation |
|---|---|---|
| Net interest income (USD) | 9,000,000 − 3,000,000 = 6,000,000 | 9,400,000 − 3,200,000 = 6,200,000 |
| Operating revenue (USD) | 6,000,000 + 2,000,000 = 8,000,000 | 6,200,000 + 1,800,000 = 8,000,000 |
| Noninterest expense (USD) | 3,000,000 + 800,000 + 700,000 + 500,000 = 5,000,000 | 3,150,000 + 820,000 + 750,000 + 580,000 = 5,300,000 |
| Efficiency ratio | 5,000,000 / 8,000,000 × 100 = 62.50% | 5,300,000 / 8,000,000 × 100 = 66.25% |
If the input table occupies A1:C8, the first-quarter formula in a percentage-formatted cell is:
=SUM(B5:B8)/(B2-B3+B4)
Copy across for the second quarter. Do not multiply by 100 inside the formula when the spreadsheet cell is already formatted as a percentage. Ratios here display two decimal places; underlying calculations remain unrounded.
The ratio rose by 66.25% − 62.50% = 3.75 percentage points. Expenses increased by $300,000, or $300,000 / $5,000,000 × 100 = 6.00%, while operating revenue stayed at $8,000,000. Higher net interest income was exactly offset by lower noninterest income.
Because the denominator is unchanged, each expense change divided by that common revenue gives its exact contribution to the ratio movement.
| Expense driver | Change (USD) | Ratio contribution (percentage points) |
|---|---|---|
| Salaries and benefits | 150,000 | 1.875 |
| Occupancy | 20,000 | 0.250 |
| Technology and processing | 50,000 | 0.625 |
| Other noninterest expense | 80,000 | 1.000 |
| Total | 300,000 | 3.750 |
Each contribution is change / 8,000,000 × 100. Their sum proves the bridge: 62.50% + 3.75 percentage points = 66.25%. The extra decimal place in this table preserves the exact contributions.
Two accounting checks come first. The selected expense accounts must tie to noninterest expense in the income statement, and net interest income plus noninterest income must tie to the defined revenue subtotal. Record excluded accounts explicitly rather than allowing missing mappings to disappear into zero.
Finance owns the definition and reconciliation. Department owners explain the salary, occupancy, processing, and other cost movements. Treasury and business leaders explain funding cost, earning-asset income, and fee-income changes.
The table identifies compensation as the largest dollar movement; it does not establish why compensation increased. Headcount, benefit rates, hiring timing, and incentive accruals need their own supporting rows. A cost increase could support a growing business or reflect temporary overlap.
At the second quarter's expense level, revenue needed to restore the first quarter's ratio is $5,300,000 / 0.625 = $8,480,000. The gap from reported revenue is $8,480,000 − $8,000,000 = $480,000. This is a sensitivity calculation holding expense fixed, not a forecast that revenue will grow without additional cost.
For other questions, financial ratios distinguish profitability and liquidity measures. The commercial banking analytics overview provides context for reviewing supplied bank reports; the broader AI analytics guide explains the files-first approach.
Bring an income-statement export with period labels, account classifications, and any approved adjustment schedule. Covirage maps the columns; its tools compute and check the supplied figures, and the external AI model explains the result with every figure traced to its rows. Create a free Covirage account, which takes about a minute, then set up your business and bring a sample of your own data.
See Covirage for cost variance analysis for the supporting reporting context.
A lower ratio means less defined operating expense relative to revenue. Read the cause before judging performance: higher revenue, lower recurring costs, and temporary gains can all change the figure. It does not establish asset quality, liquidity, or service outcomes.
The terms generally describe operating costs relative to operating income. Published calculations can differ in their treatment of amortization, securities gains, tax-equivalent income, or unusual costs. Reconcile the definitions before treating two reported percentages as directly comparable.
In the convention used here, interest expense reduces interest income to produce net interest income in the denominator. The numerator contains noninterest expenses. Adding interest expense again to that numerator would create a different measure and count its effect twice.
A combined ratio divides combined defined expenses by combined defined revenues. A simple average gives small and large branches equal weight. Branch comparisons also need consistent central-cost allocations and internal funding charges before the combined figure is meaningful.