Claims are not the only cost of providing insurance. The expense ratio measures underwriting and administrative expenses as a percentage of written or earned premium. It shows how much of each premium dollar is consumed by commissions, salaries, technology, and overhead rather than by claims.

A lower expense ratio indicates greater operational efficiency, all else equal. Direct writers often show lower commission expense than agency companies, while complex commercial lines may require higher underwriting and loss-control costs. The ratio is one component of the combined ratio.

Management tracks the expense ratio over time and against peers. Sudden growth can temporarily inflate the ratio if fixed costs lag; aggressive expense cutting can impair service or underwriting quality. Sustainable profitability requires both loss control and disciplined expense management.

• Underwriting expenses as a percent of premium
• Measures operational efficiency
• Component of the combined ratio
• Varies by distribution system and line of business