Pc Insurance & Reinsurance (Ark/Wm Outrigger) was White Mountains Insurance’s largest segment in fiscal 2025, bringing in $1.94B of $3.74B (52%).
| Segment | FY 2009 | FY 2010 | FY 2011 | FY 2012 | FY 2013 | FY 2014 | FY 2016 | FY 2017 | FY 2018 | FY 2019 | FY 2020 | FY 2021 | FY 2022 | FY 2023 | FY 2024 | FY 2025 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| One Beacon | — | — | — | — | ||||||||||||
| Pc Insurance & Reinsurance (Ark/Wm Outrigger) | $1.01B | $1.56B | $1.75B | $1.94B | ||||||||||||
| Onebeacon | — | — | — | — | ||||||||||||
| Sirius Group | — | — | — | — | ||||||||||||
| Ark Insurance Holdings Limited/Outrigger | — | — | — | — | ||||||||||||
| Other Operations | $76.30M | $339.40M | $234.90M | $1.23B | ||||||||||||
| Other | — | — | — | — | ||||||||||||
| Pc Insurance Distribution (Bamboo) | — | — | $179.80M | $246.30M | ||||||||||||
| Nsm | — | — | — | — | ||||||||||||
| Mediaalpha | — | — | — | — | ||||||||||||
| Asset Management (Kudu) | $118.50M | $177.10M | $118.80M | $183.40M | ||||||||||||
| Other Segments | — | — | — | — | ||||||||||||
| Specialty Insurance Distribution (Distinguished) | — | — | — | $57.70M | ||||||||||||
| Hg Global-Bam | — | — | — | — | ||||||||||||
| Kudu | — | — | — | — | ||||||||||||
| Hg Global | — | — | — | — | ||||||||||||
| Financial Guarantee (Hg Global) | -$46.40M | $92.40M | -$44.60M | $73.60M | ||||||||||||
| Hg Global/Bam - | — | — | — | — | ||||||||||||
| Bam | — | — | — | — | ||||||||||||
| Total | $1.16B | $2.17B | $2.24B | $3.74B |
White Mountains Insurance brought in $3.74B from its six segments in fiscal 2025, the year ended December 31, 2025. White Mountains Insurance regrouped these segments after fiscal 2024, so the total does not compare directly with that year's $2.24B. Pc Insurance & Reinsurance (Ark/Wm Outrigger) was the largest at $1.94B (52.0%), ahead of Other Operations at $1.23B (32.9%) and Pc Insurance Distribution (Bamboo) at $246.30M (6.6%). The other three segments brought in $314.70M combined.
Compared with fiscal 2024, Other Operations grew fastest, up 423.7% to $1.23B. Every segment above 2% of revenue grew.
White Mountains Insurance began breaking out Pc Insurance Distribution (Bamboo) in fiscal 2024 and Specialty Insurance Distribution (Distinguished) in fiscal 2025.
Onebeacon was White Mountains Insurance’s largest revenue line in fiscal 2016, bringing in $1.10B of $1.34B (82%).
| Disposal Group Name | FY 2016 |
|---|---|
| Onebeacon | $1.10B |
| Sirius Group | $240.10M |
| Total | $1.34B |
White Mountains Insurance brought in $1.34B from its two revenue lines in fiscal 2016, the year ended December 31, 2016. Onebeacon was the largest at $1.10B (82.1%), ahead of Sirius Group at $240.10M (17.9%).
Other was White Mountains Insurance’s largest revenue line in fiscal 2015, bringing in $319.10M of $435.30M (73%).
| Legal Entity | FY 2015 |
|---|---|
| Other | $319.10M |
| Mediaalpha | $105.50M |
| Hg Global Bam | $10.70M |
| Total | $435.30M |
White Mountains Insurance brought in $435.30M from its three revenue lines in fiscal 2015, the year ended December 31, 2015. Other was the largest at $319.10M (73.3%), ahead of Mediaalpha at $105.50M (24.2%) and Hg Global Bam at $10.70M (2.5%).
White Mountains Insurance (WTM) reports its revenue by segment, by disposal group name and by legal entity. In fiscal 2025, Pc Insurance & Reinsurance (Ark/Wm Outrigger) was its largest segment, bringing in $1.94B (52.0% of the total), followed by Other Operations at $1.23B (32.9%).
Pc Insurance & Reinsurance (Ark/Wm Outrigger) was White Mountains Insurance's largest segment in fiscal 2025, bringing in $1.94B, or 52.0% of the $3.74B total across its six segments.
Onebeacon was White Mountains Insurance's largest revenue line in fiscal 2016, bringing in $1.10B, or 82.1% of the $1.34B total across its two revenue lines.
Every figure comes from White Mountains Insurance's annual financial filings, as reported. Each line keeps the name White Mountains Insurance gives it, and years follow its fiscal calendar.
White Mountains Insurance's revenue by segment goes back to fiscal 2009, with figures through fiscal 2025. The latest four fiscal years are free to view, and the full history is available with a Business Quant subscription.