Excess and surplus lines used to be the market's overflow valve — the place carriers and agents turned when standard markets wouldn't touch a risk. That framing no longer fits. According to S&P Global Market Intelligence's 2025 U.S. Excess & Surplus Market Report, cited by Insurance Journal, full-year 2024 E&S direct premiums written hit $98.2 billion nationally, up from $86.6 billion in 2023 and $75.5 billion in 2022. Growth has cooled from the breakneck 32.3% pace of 2021, landing at 13.4% in 2024 versus 14.5% the year before — but even a 'slowdown' at this scale is still adding billions in new premium every year.
The bigger story is share of wallet. AM Best's Annual Surplus Lines Report, as reported by Insurance Journal, shows E&S premium climbing from just 3.6% of total U.S. property/casualty premium in 2000 to 12.3% in 2024. Narrow that to commercial lines specifically, and E&S now represents 25.7% of the pie. One in four commercial dollars is now moving through the surplus lines channel rather than admitted paper.
Momentum hasn't let up in 2025. Insurance Journal reported mid-year surplus lines premium across the 15 state stamping and service offices reached $46.2 billion, a 13.2% year-over-year increase, built on 3.7 million filed items — a 12.4% rise in item count. That growth wasn't uniform: Idaho was the only one of the 15 stamping states to post a mid-2025 decline, down 16%, according to Surplus Line Association of Idaho executive Carrie Negrette, even though the state's volume remains up 82% since mid-2022. The lesson for agency owners is that E&S growth is lumpy by geography and line, not a rising tide that lifts every book equally.
Underneath the aggregate numbers, the mix is shifting too. S&P Global Market Intelligence data via Insurance Journal shows E&S liability premiums — across the four liability lines the firm tracks — grew 12.4% in 2024, while E&S property growth decelerated sharply to 15.4% after a 40.6% spike in 2023. Property is normalizing after a hard-market surge; liability is the newer growth engine, and large wholesale brokers are leaning into it. Ryan Specialty's RT Specialty CEO Tim Turner told Insurance Journal the firm continues to post 20%-plus annual growth and expects to write more than $30 billion in premium in 2025, pointing to hardening niches like social and human services and public entity risk as drivers.
What this means for agency value. None of this shows up as a line item on an agency's P&L — it shows up in carrier access. Public licensing and carrier-appointment records show the gap between well-connected and thin agencies is real and measurable at the metro level. In Texas, the median independent agency holds 6 to 9 carrier appointments depending on metro, with single-carrier dependency running 6-7% of agencies. Florida agencies carry more appointments on average — medians of 12 to 15 across Tampa, Orlando, Miami, and Jacksonville — but even there, 3-7% of agencies still operate on a single carrier, a structural vulnerability regardless of E&S exposure.
Agencies that have built wholesale relationships and developed genuine specialty underwriting knowledge — construction defect, habitational, excess casualty, public entity — are the ones able to actually place the E&S growth carriers are pushing into the channel. Standard-market-only shops aren't necessarily shrinking in absolute terms, but they're shrinking relative to a commercial P&C pie where a quarter of the dollars now flow somewhere they can't reach. Valuation advisory firms have long noted that buyers pay premiums for specialty and wholesale capability versus commoditized personal or standard commercial lines books, though actual multiples vary widely by book mix, retention, and carrier diversification — owners should treat any specific multiple quoted to them with skepticism absent a firm-specific analysis from a reputable M&A advisory shop.
For agency owners assessing where they sit, the practical questions are carrier-appointment depth, single-carrier exposure, and whether the agency has any wholesale or E&S access at all. For a market-level view of how carrier access breaks down by metro, see Pexara's Texas market intelligence and Florida market intelligence.