v3.26.1
Third-Party Reinsurance (Tables)
 6 Months Ended
Jun. 30, 2026
Reinsurance Disclosures [Abstract]  
Effects of reinsurance
The following table summarizes the effects of reinsurance on written and earned premiums and loss and LAE for the Ark/WM Outrigger segment for the three and six months ended June 30, 2026 and 2025:
Three Months Ended June 30,Six Months Ended June 30,
Millions2026202520262025
Written premiums:
Direct$373.6 $356.6 $730.9 $773.4 
Assumed403.9 458.6 1,137.5 1,149.4 
Gross written premiums777.5 815.2 1,868.4 1,922.8 
Ceded (1)
(240.1)(236.6)(740.9)(616.5)
Net written premiums$537.4 $578.6 $1,127.5 $1,306.3 
Earned premiums:
Direct$288.2 $260.1 $554.9 $506.4 
Assumed242.3 209.0 479.1 423.1 
Gross earned premiums530.5 469.1 1,034.0 929.5 
Ceded (2)
(154.3)(104.9)(284.0)(207.3)
Net earned premiums$376.2 $364.2 $750.0 $722.2 
Loss and LAE:
Gross$354.8 $197.0 $618.8 $520.2 
Ceded (3)
(179.2)(33.0)(236.5)(122.7)
Net loss and LAE$175.6 $164.0 $382.3 $397.5 
(1) The three months ended June 30, 2026 and 2025 exclude written premiums of $(0.4) and $42.6, and the six months ended June 30, 2026 and 2025 exclude written premiums of $(0.4) and $80.1 ceded by Ark to WM Outrigger Re, which eliminate in White Mountains’s consolidated financial statements.
(2) The three months ended June 30, 2026 and 2025 exclude earned premiums of $0.8 and $7.1, and the six months ended June 30, 2026 and 2025 exclude earned premiums of $3.5 and $19.1 ceded by Ark to WM Outrigger Re, which eliminate in White Mountains’s consolidated financial statements.
(3) The three months ended June 30, 2026 and 2025 exclude loss and LAE of $(0.1) and $1.7, and the six months ended June 30, 2026 and 2025 exclude $0.2 and $21.9 ceded by Ark to WM Outrigger Re, which eliminate in White Mountains’s consolidated financial statements.

The following table presents the Ark/WM Outrigger segment’s reinsurance recoverables as of June 30, 2026 and December 31, 2025:
Millions
June 30, 2026December 31, 2025
Reinsurance recoverables on unpaid losses (1)
$570.0 $508.3 
Reinsurance recoverables on paid losses (2)
157.0 117.6 
Ceded unearned premiums (3)
667.0 210.2 
Reinsurance recoverables
$1,394.0 $836.1 
(1) The reinsurance recoverables on unpaid losses exclude $25.0 and $29.5 ceded by Ark to WM Outrigger Re as of June 30, 2026 and December 31, 2025, which eliminate in White Mountains’s consolidated financial statements.
(2) The reinsurance recoverables on paid losses exclude $2.6 and $5.2 ceded by Ark to WM Outrigger Re as of June 30, 2026 and December 31, 2025, which eliminate in White Mountains’s consolidated financial statements.
(3) The ceded unearned premiums exclude $0.0 and $3.9 ceded by Ark to WM Outrigger Re as of June 30, 2026 and December 31, 2025, which eliminate in White Mountains’s consolidated financial statements.
The following table presents gross written premiums and gross earned premiums included in the HG Global segment for the three and six months ended June 30, 2026 and 2025:
Three Months Ended June 30,Six Months Ended June 30,
Millions2026202520262025
Written premiums:
Direct$— $— $— $— 
Assumed11.0 19.2 19.3 25.9 
Gross written premiums
$11.0 $19.2 $19.3 $25.9 
Earned premiums:
Direct$— $— $— $— 
Assumed7.7 7.1 15.4 15.3 
Gross earned premiums
$7.7 $7.1 $15.4 $15.3 
Gross and net reinsurance recoverables by reinsurers ratings
The following table presents the Ark/WM Outrigger segment’s gross and net reinsurance recoverables by the reinsurers’ A.M. Best Company, Inc (“A.M. Best”) ratings as of June 30, 2026:
$ in MillionsAs of June 30, 2026
A.M. Best Rating (1)
GrossCollateralNet% of Total
A+ or better$467.8 $— $467.8 68.6 %
A- to A202.6 — 202.6 29.7 
B++ or lower and not rated (2)
56.6 45.3 11.3 1.7 
Total$727.0 $45.3 $681.7 100.0 %
(1) A.M. Best financial strength ratings as detailed above are: “A+ or better” (Superior) “A- to A” (Excellent), “B++” (Good).
(2) Excludes $27.6 ceded by Ark to WM Outrigger Re as of June 30, 2026, which eliminates in White Mountains’s consolidated financial statements.