Onex Corp stock in focus as portfolio company Convex reports robust Q4 2025 results boosting investor interest

Onex Corp (ISIN: CA68272K1030), the Canadian investment holding company, sees heightened attention from US investors following strong Q4 2025 supplemental data from its key portfolio firm Convex Insurance. The release highlights significant growth in premiums, net income, and tangible book value, underscoring Onex's strategy of backing high-performing insurers amid favorable market conditions.

Onex Corp stock has drawn fresh scrutiny from investors after its major portfolio company, Convex Insurance, released supplemental Q4 2025 information showing robust financial performance. The data reveals a 13.8% year-over-year increase in gross premiums written to $5,879 million for the full year 2025, alongside a 40.5% jump in net income to $711 million. This development matters now because it validates Onex's long-term investment approach in the insurance sector, particularly as US investors seek stable, growth-oriented holdings in a volatile market.

As of: 24.03.2026

By Elena Voss, Senior Financial Analyst specializing in alternative investments and insurance-linked assets. Convex's strong metrics highlight Onex Corp's effective portfolio management in a sector poised for continued expansion.

Convex Q4 2025 Highlights Drive Onex Corp Momentum

Convex, a specialist insurer in Onex's portfolio, posted impressive figures in its Q4 2025 supplemental package. Gross premiums written reached $891 million in the quarter, contributing to full-year growth of 13.8% from $5,166 million in 2024. Net premiums earned climbed 19.6% to $3,673 million annually, with the quarter alone at $957 million.

Underwriting discipline remained strong, evidenced by a combined ratio of 89.0% for the year. Losses and loss expenses rose 21.9% to $1,980 million but stayed manageable relative to premium growth. Net investment return surged 43.6% to $395 million, reflecting savvy asset allocation in a higher-yield environment.

These results directly bolster Onex Corp's position as a holding company that thrives on portfolio company success. Investors view such updates as leading indicators of potential distributions or valuation uplifts for Onex shares.

Onex Corp's Portfolio Strategy Under the Spotlight

Onex Corp operates as an investment holding company, with Convex representing a cornerstone of its insurance-focused investments. The firm's model involves acquiring controlling stakes in businesses and nurturing them for long-term value creation. Convex's performance exemplifies this, with tangible book value excluding deferred tax assets and preferred equity rising 23.5% to $3,834 million from $3,105 million a year earlier.

Total capital stood at $4,334 million, up 20.2%, supporting an annualized return on average tangible equity of 20.0%. This outperforms the prior year's 17.4%, signaling operational leverage. Onex benefits indirectly through equity stakes and potential exit opportunities, making these metrics critical for stock valuation.

Market participants are parsing how Convex's $7.3 billion investment portfolio—89% in investment-grade fixed income with a AA- average rating and 2.4-year duration—positions Onex for sustained returns. Equities and structured products add diversification, contributing to the 5.9% YTD net investment return.

Underwriting Strength and Loss Control in Focus

Convex's current accident year loss ratio excluding catastrophes held steady, with prior year development at -4.2%, aiding overall profitability. Total loss ratio was 53.9%, marginally above 53.0% last year but supported by premium expansion. Net acquisition costs increased 30.5% to $761 million, reflecting scale.

Gross premiums split evenly between insurance ($3.2 billion) and reinsurance ($2.7 billion), with casualty and property leading. Specialty lines like marine, aerospace, and energy add resilience. This diversified book appeals to Onex investors seeking exposure to non-cyclical revenue streams.

For Onex Corp stock, these details underscore the portfolio's resilience. Consistent growth in net premiums written—15.3% to $4,075 million—positions the holding company for fee income and carried interest potential.

Why US Investors Should Watch Onex Corp Now

US investors find Onex Corp compelling due to its access to global insurance markets without direct operational risk. Convex's US GAAP net income calculation and exposure to American asset classes, like agency MBS and corporate bonds, align with familiar dynamics. The firm's $7.3 billion portfolio includes 31% government bonds and 13% CLOs/loans, mirroring US fixed income strategies.

In a landscape of elevated interest rates, Convex's low-duration portfolio (2.4 years) minimizes rate sensitivity while capturing yield. Onex provides US portfolios with Canadian-listed diversification, trading primarily on the Toronto Stock Exchange in Canadian dollars. This cross-border appeal grows as US funds seek uncorrelated returns.

Recent supplemental data reinforces Onex's narrative of value creation through active management. With tangible book value per share evolution showing steady climbs—$3,834 million latest—investors anticipate ripple effects on Onex Corp stock performance.

Investment Portfolio Breakdown Signals Stability

Convex's investments total $7.3 billion as of December 31, 2025, excluding $0.6 billion in cash and short-term assets. Above investment grade fixed income dominates at 89%, with weighted average credit rating AA-. Corporate bonds (32%), ABS (13%), and RMBS/CMBS (11%) provide yield pickup.

Equities comprise 4%, other assets 3%, balancing risk. YTD net investment return of 5.9% outpaces benchmarks, driven by fixed income duration management. For Onex Corp, this portfolio strength supports preference share dividends of $52 million annually, stable at $13 million quarterly.

US investors appreciate this conservative tilt, especially amid equity volatility. Onex's oversight ensures alignment with shareholder interests, potentially driving stock appreciation.

Risks and Open Questions for Onex Corp Stock

Despite strengths, catastrophe exposure in property and specialty lines poses risks, though current year loss ratios exclude these. Prior year development improved but remains a watch point at -4.2%. Operating expenses rose 7.9% to $480 million, pressuring margins if premiums soften.

Preference shares at $500 million represent fixed obligations, with total capital at $4,334 million offering buffer. Market sensitivity to reinsurance pricing cycles could impact gross premiums. Onex faces portfolio concentration risk if Convex stumbles, though diversification mitigates.

Regulatory changes in insurance solvency or investment rules could alter dynamics. Investors should monitor quarterly updates for sustained underwriting profitability. Overall, while metrics shine, vigilance on loss trends remains essential.

Disclaimer: This is not investment advice. Stocks are volatile financial instruments.