Exhibit 99.1

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The Hanover Reports Fourth Quarter Net Income and

Operating Income of $2.98 and $3.13 per Diluted Share, Respectively;

Net and Operating Return on Equity of 18.8% and 15.7%, Respectively

Fourth Quarter Highlights

Full Year Highlights

*Unless otherwise stated, net premiums written growth and other growth comparisons are to the same period of the prior year

(1) See information about this and other non-GAAP measures and definitions used throughout this press release on the final pages of this document.

The Hanover Insurance Group, Inc. may also be referred to as “The Hanover” or “the company” interchangeably throughout this press release.

WORCESTER, Mass., Jan. 31, 2024 - The Hanover Insurance Group, Inc. (NYSE: THG) today reported net income of $107.9 million, or $2.98 per diluted share, in the fourth quarter of 2023, compared to a net loss of $12.1 million, or $0.34 per basic share, in the prior-year quarter. Operating income(4) was $113.1 million, or $3.13 per diluted share, in the fourth quarter of 2023, compared to an operating loss of $37.4 million, or $1.05 per basic share, in the prior-year quarter.

Net income was $35.3 million, or $0.98 per diluted share, in the full year 2023. This compared to net income of $116.0 million, or $3.21 per diluted share, in the prior year. Operating income was $56.2 million, or $1.56 per diluted share, in 2023, compared to operating income of $199.9 million, or $5.53 per diluted share, in the prior year, primary attributable to elevated catastrophe losses through the first three quarters of the year compared to 2022.

“The fourth quarter represented a strong finish to a very productive year, as we delivered operating return on equity(5) of 15.7% and a combined ratio of 94.2%, demonstrating meaningful improvement in each of our business segments and validating the strong execution of our margin recapture program,” said John C. Roche, president and chief executive officer at The Hanover. “We achieved double digit renewal pricing across all three of our business segments, executed underwriting initiatives and product changes in property lines, and implemented new loss control and preventive measures, taking meaningful steps to reposition our property business to address inflation and changing weather patterns. While topline growth decelerated at the tail end of the year as a result of our proactive actions, we have positioned ourselves to reaccelerate production and take advantage of robust opportunities in 2024 in multiple segments and geographies, where profitability profiles are very attractive.”

“Having delivered on our most critical underlying operating and financial targets for 2023, including ex-CAT combined ratio, we enter 2024 with an increased confidence in our profitability and growth trajectory, with the foundation of our proven strategy, capabilities and distribution distinctiveness, as well as our talented and determined team focused on delivering strong and sustainable value for our shareholders and all of our stakeholders,” Roche concluded.

“Our fourth quarter current accident year loss and LAE ratio, excluding catastrophes, of approximately 60% improved over 3 points compared to the prior-year quarter,” said Jeffrey M. Farber, executive vice president and chief financial officer at The Hanover. “Fourth quarter catastrophe losses of 4.0% included 2.8 points from fourth quarter events and 1.2 points from prior-quarter reserve re-estimates. We achieved renewal price increases of 20.6% in Personal Lines, 12.4% in Core Commercial and 11.6% in Specialty. We grew net investment income significantly in the quarter and the year, primarily due to higher bond reinvestment rates and the continued investment of operational cashflows. We expect investment income to continue to meaningfully augment operating results in the years ahead. We are very optimistic about our position and confident in our strong outlook for 2024, including further enhancement of our ex-CAT combined ratio, supported by robust improvement in Personal Lines, continued strong profitability in Specialty and Core Commercial, and overall solid growth for the enterprise, led by Specialty.”

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Fourth Quarter and Full Year 2023 Highlights

Fourth Quarter Operating Highlights

Core Commercial

Core Commercial operating income before income taxes was $52.8 million in the fourth quarter of 2023, compared to an operating loss before income taxes of $52.7 million in the fourth quarter of 2022. The Core Commercial combined ratio was 96.7%, compared to 117.2% in the prior-year quarter. Catastrophe losses in the fourth quarter of 2023 were $29.5 million, or 5.7 points of the combined ratio. This compared to catastrophe losses of $123.5 million, or 24.6 points, in the prior-year quarter.

Fourth quarter 2023 results included net favorable prior-year reserve development, excluding catastrophes, of $2.2 million, or 0.4 points, driven by continued favorability in workers’ compensation. This compared to $2.4 million, or 0.5 points, in the fourth quarter of 2022.

Core Commercial current accident year combined ratio, excluding catastrophes, improved 1.7 points to 91.4% in the fourth quarter of 2023, from 93.1% in the prior-year quarter. The current accident year loss and LAE ratio, excluding catastrophes, of 57.8%, decreased 2.4 points from the prior-year quarter, driven by the benefit of earned pricing above loss trends and consistently lower large losses in commercial multiple peril, primarily in middle market, following the execution of underwriting actions.

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The expense ratio increased by 0.7 points to 33.6% in the fourth quarter of 2023, compared to the prior-year quarter, primarily due to continued strategic business and talent investments, which were partially offset by fixed cost leverage from earned premium growth.

Net premiums written were $465.5 million in the quarter, up 2.7% from the prior-year quarter, consisting of 6.0% growth in small commercial and a decline of 1.7% in middle market. In the fourth quarter, Core Commercial renewal price increases averaged 12.4%, while average rate increases were 9.3%.

The following table summarizes premiums and the components of the combined ratio for Core Commercial:

Specialty

Specialty operating income before income taxes was $70.5 million in the fourth quarter of 2023, compared to $43.9 million in the fourth quarter of 2022. The Specialty combined ratio was 83.2%, compared to 90.5% in the prior-year quarter. Catastrophe losses in the fourth quarter of 2023 were $5.6 million, or 1.7 points of the combined ratio, compared to $9.9 million, or 3.2 points, in the prior-year quarter.

Fourth quarter 2023 results included net favorable prior-year reserve development, excluding catastrophes, of $14.0 million, or 4.4 points, driven primarily by lower-than-expected losses in our professional and executive lines claims-made business. This compared to immaterial prior-year reserve development, excluding catastrophes, in the prior-year quarter.

Specialty current accident year combined ratio, excluding catastrophes, decreased 1.4 points to 85.9% in the fourth quarter of 2023, from 87.3% in the prior-year quarter. The current accident year loss and LAE ratio, excluding catastrophes, decreased 2.0 points to 49.5% in the fourth quarter of 2023, primarily driven by the benefit of earned pricing above loss trends and lower-than-expected losses in Marine.

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The expense ratio increased by 0.6 points to 36.4% in the fourth quarter of 2023, compared to the prior-year quarter, primarily due to continued strategic business and talent investments, which were partially offset by fixed cost leverage from earned premium growth.

Net premiums written were $304.9 million in the quarter, down 1.5% from the prior-year quarter, primarily from the continued impact of non-renewal of certain programs in Specialty Property and Casualty. In the fourth quarter, Specialty renewal price increases averaged 11.6%, while average rate increases were 9.0%.

The following table summarizes premiums and the components of the combined ratio for Specialty:

Personal Lines

Personal Lines operating income before income taxes was $36.8 million in the fourth quarter of 2023, compared to an operating loss before income taxes of $29.1 million in the fourth quarter of 2022. The Personal Lines combined ratio was 97.6%, compared to 109.1% in the prior-year quarter. Catastrophe losses in the fourth quarter of 2023 were $22.6 million, or 3.8 points of the combined ratio. This compared to catastrophe losses of $56.2 million, or 10.2 points of the combined ratio, in the prior-year quarter.

Fourth quarter 2023 results included net unfavorable prior-year reserve development, excluding catastrophes, of $4.8 million, or 0.8 points, driven primarily by umbrella, which is reported in homeowners and other. This compared to immaterial prior-year reserve development, excluding catastrophes, in the prior-year quarter.

Personal Lines current accident year combined ratio, excluding catastrophe losses, decreased 5.9 points to 93.0% in the fourth quarter of 2023, from 98.9% in the prior-year quarter. The current accident year loss and LAE ratio, excluding catastrophes, decreased 4.6 points from the prior-year quarter to 68.0%, driven by the benefit of earned pricing outpacing loss trends in both personal auto and homeowners, as well as improved loss trends in auto collision coverage, and lower loss frequency due to benign weather conditions.

The expense ratio decreased by 1.3 points to 25.0% in the fourth quarter of 2023, compared to the prior-year quarter, primarily due to lower variable agency compensation and fixed cost leverage from earned premium growth.

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Net premiums written were $575.1 million in the quarter, up 2.1% from the prior-year quarter, driven primarily by renewal price change. Personal Lines renewal price increases averaged 20.6%, while average rate increases were 13.2%. Policies in force in the fourth quarter decreased 2.3% compared to the third quarter of 2023, including a 3.3% decrease in the Midwest.

The following table summarizes premiums and components of the combined ratio for Personal Lines:

Full Year Underwriting Highlights

The company's combined ratio was 103.5% in the full year of 2023, compared to 99.8% in the prior year. Catastrophe losses were $690.1 million, or 12.2 points of the combined ratio, in 2023, driven by severe convective storms in the first three quarters of 2023, primarily in the Midwestern United States, mostly impacting Personal Lines. This compared to $402.6 million, or 7.7 points, in the prior year. Net favorable prior-year reserve development, excluding catastrophes, was $15.9 million, or 0.3 points, in 2023, compared to $20.6 million, or 0.4 points in the prior year.

The current accident year combined ratio, excluding catastrophe losses, was 91.6% in 2023, compared to 92.5% in the prior year, driven by an improvement in the current accident year loss and LAE ratio, excluding catastrophes, and the expense ratio. The current accident year loss and LAE ratio, excluding catastrophes, improved 0.6 points primarily due to the benefit of earned pricing in each segment. The expense ratio improved 0.3 points in the full year of 2023, compared to the prior year, driven primarily by the benefit of fixed cost leverage.

Total net premiums written were $5.8 billion in 2023, up 6.1% from 2022, reflecting growth of 7.9% in Personal Lines, 5.4% in Core Commercial and 4.0% in Specialty, slowed by the non-renewal of certain programs in Specialty Property and Casualty in the third and fourth quarters.

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Core Commercial operating income before taxes was $167.2 million in 2023, which included $171.3 million, or 8.3 points, of catastrophe losses, and $4.7 million, or 0.2 points, of net unfavorable prior-year reserve development. In 2022, Core Commercial operating income before taxes was $106.9 million, which included $193.7 million, or 9.9 points, of catastrophe losses, and $10.3 million, or 0.5 points, of net favorable prior-year reserve development. The Core Commercial current accident year combined ratio, excluding catastrophe losses, was 90.5%, compared to 91.8% in the prior year, driven by improvement in the current accident year loss and LAE ratio, excluding catastrophes, primarily due to lower large losses in commercial multiple peril, partially offset by an increase of 0.5 points in the expense ratio.

Specialty operating income before taxes was $243.5 million in 2023, which included $43.1 million, or 3.4 points, of catastrophe losses, and $48.8 million, or 3.8 points, of net favorable prior-year reserve development. In 2022, Specialty operating income before taxes was $186.0 million, which included $32.7 million, or 2.8 points, of catastrophe losses, and $19.5 million, or 1.6 points, of net favorable prior-year reserve development. The Specialty current accident year combined ratio, excluding catastrophe losses, was 86.6%, compared to 88.1% in the prior year, driven by an improvement in the current accident year loss and LAE ratio, excluding catastrophes, primarily due to the benefit from rate increases earning-in and lower-than-expected losses in Marine, partially offset by an increase of 0.2 points in the expense ratio.

Personal Lines operating loss before taxes was $304.3 million in 2023, which included $475.7 million, or 20.4 points, of catastrophe losses, and $25.9 million, or 1.1 points, of net unfavorable prior-year reserve development. In 2022, Personal Lines operating loss before taxes was $8.8 million, which included $176.2 million, or 8.3 points, of catastrophe losses, and $8.0 million, or 0.4 points, of net unfavorable prior-year reserve development. The Personal Lines current accident year combined ratio, excluding catastrophes, was 95.6%, in line with the prior year, reflecting a decrease of 1.0 point in the expense ratio, offset by a higher current accident year loss ratio, excluding catastrophes, in the first half of 2023.

Investments

Net investment income was $81.6 million for the fourth quarter and $332.1 million for the full year 2023, above prior-year periods primarily due to higher bond reinvestment rates and continued investment of operational cashflows, partially offset by lower partnership income. Total pre-tax earned yield on the investment portfolio for the fourth quarter 2023 was 3.40%, up from 3.26% in the prior-year quarter. The average pre-tax earned yield on fixed maturities was 3.46% for the fourth quarter of 2023, up from 3.20% in the prior-year quarter. Total pre-tax earned yield on the investment portfolio for the full year 2023 was 3.50%, up from 3.29% in the prior year. The average pre-tax earned yield on fixed maturities was 3.36% for the full year 2023, up from 3.04% in the prior year.

Net realized and unrealized investment losses recognized in earnings were $0.7 million in the fourth quarter of 2023, compared to net realized and unrealized investment gains recognized in earnings of $32.2 million in the fourth quarter of 2022. Net realized and unrealized investment losses recognized in earnings were $32.5 million in 2023, primarily driven by intent to sell fixed maturity securities and credit-related impairments, as well as losses on the sale of fixed maturity securities. This compared to net realized and unrealized investment losses recognized in earnings of $106.5 million in 2022.

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The company held $9.2 billion in cash and invested assets on December 31, 2023. Fixed maturities and cash represented approximately 90% of the investment portfolio. Approximately 95% of the company’s fixed maturity portfolio is rated investment grade. As of December 31, 2023, net unrealized losses on the fixed maturity portfolio were $588.6 million before income taxes, an increase in fair value of $328.6 million since September 30, 2023, and $224.1 million since December 31, 2022.

Shareholders’ Equity and Capital Actions

On December 31, 2023, book value per share was $68.93, up 16.4% from September 30, 2023, primarily due to an increase in the fair value of fixed maturity investments, as well as retained earnings. Book value per share, excluding net unrealized depreciation on fixed maturity investments, net of tax(7), was $81.86 at December 31, 2023, compared to $79.38 at September 30, 2023. During the quarter, the company did not repurchase any shares of common stock. The company has approximately $330 million of remaining capacity under its existing share repurchase program.

On December 31, 2023, operating subsidiary’s statutory capital and surplus was $2.64 billion. This compared to statutory capital and surplus of $2.50 billion on September 30, 2023.

Additionally, in the fourth quarter, the Board of Directors approved an increase to the quarterly dividend of 5% to $0.85 per common share. The company paid ordinary dividends of $30.3 million in the fourth quarter and $117.2 million in the year.

Earnings Conference Call

The company will host a conference call to discuss its fourth quarter results on Thursday, February 1, at 10:00 a.m. E.T. A presentation will accompany the prepared remarks and has been posted on The Hanover’s website. Interested investors and others can listen to the call and access the presentation through The Hanover's website, located in the “Investors” section at www.hanover.com. Investors may access the conference call by dialing 1-844-413-3975 in the U.S. and 1-412-317-5458 internationally. Webcast participants should go to the website 15 minutes early to register, download and install any necessary audio software. A re-broadcast of the conference call will be available on The Hanover’s website approximately two hours after the call.

About The Hanover

The Hanover Insurance Group, Inc. is the holding company for several property and casualty insurance companies, which together constitute one of the largest insurance businesses in the United States. The company provides exceptional insurance solutions through a select group of independent agents and brokers. Together with its agent partners, the company offers standard and specialized insurance protection for small and mid-sized businesses, as well as for homes, automobiles, and other personal items. For more information, please visit hanover.com.

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Definition of Reported Segments

Continuing operations include four operating segments: Core Commercial, Specialty, Personal Lines and Other. The Core Commercial segment includes commercial multiple peril, commercial automobile, workers’ compensation and other commercial lines coverages provided to small and mid-sized businesses. The Specialty segment includes four divisions of business: professional and executive lines, specialty property and casualty (“Specialty P&C”), marine, and surety and other. Specialty P&C includes coverages such as program business (provides commercial insurance to markets with specialized coverage or risk management needs related to groups of similar businesses), specialty industrial and commercial property, excess and surplus lines, and specialty general liability coverage. The Personal Lines segment markets automobile, homeowners and ancillary coverages to individuals and families. The “Other” segment includes Opus Investment Management, Inc., which provides investment management services to institutions, pension funds and other organizations, and the operations of the holding company, as well as a block of run-off voluntary assumed property and casualty pools business in which the company has not actively participated since 1995, and run-off direct asbestos and environmental business and product liability businesses.

Financial Supplement

The Hanover's fourth quarter and full year news release and financial supplement are available in the “Investors” section of the company’s website at hanover.com.

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The following is a reconciliation from operating income (loss) to net income (loss)(4)(8):

*Per share data is calculated using basic shares outstanding due to antidilution.

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Forward-Looking Statements and Non-GAAP Financial Measures

Forward-Looking Statements

Certain statements in this document and comments made by management may be “forward-looking statements” as defined in the Private Securities Litigation Reform Act of 1995. All statements, other than statements of historical facts, may be forward-looking statements. Words such as, but not limited to, “believes,” “anticipates,” “expects,” “intends,” “may,” “projects,” “projections,” “plan,” “likely,” “potential,” “targeted,” “forecasts,” “should,” “could,” “continue,” “outlook,” “guidance,” “modeling,” “target profitability,” “target margins,” “confident,” “will,” and other similar expressions are intended to identify forward-looking statements. Forward-looking statements by their nature address matters that are, to different degrees, uncertain. The company cautions investors that any such forward-looking statements are estimates, beliefs, expectations and/or projections that involve significant judgment, and that historical results, trends and forward-looking statements are not guarantees and are not necessarily indicative of future performance. Actual results could differ materially from those anticipated.

These statements include, but are not limited to, the company’s statements regarding:

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Additional Risks and Uncertainties

Investors are further cautioned and should consider the risks and uncertainties in the company’s business that may affect such estimates and future performance that are discussed in the company’s most recently filed reports on Form 10-K and Form 10-Q and other documents filed by The Hanover Insurance Group, Inc. with the Securities and Exchange Commission (“SEC”) and that are also available at www.hanover.com under “Investors.” These risks and uncertainties include, but are not limited to:

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Investors should not place undue reliance on forward-looking statements, which speak only as of the date they are made and should understand the risks and uncertainties inherent in or particular to the company’s business. The company does not undertake the responsibility to update or revise such forward-looking statements, except as required by law.

Non-GAAP Financial Measures

As discussed on page 38 of the company’s Annual Report on Form 10-K for the year ended December 31, 2022, the company uses non-GAAP financial measures as important measures of its operating performance, including operating income (loss), operating income (loss) before interest expense and income taxes, operating income (loss) per diluted (basic) share, and components of the combined ratio, both excluding and/or including catastrophe losses, prior-year reserve development and the expense ratio. Management believes these non-GAAP financial measures are important indications of the company’s operating performance. The definition of other non-GAAP financial measures and terms can be found in the 2022 Annual Report on pages 63-66.

Operating income (loss) and operating income (loss) per diluted (basic) share are non-GAAP measures. They are defined as net income (loss) excluding the after-tax impact of net realized and unrealized investment gains (losses), gains and/or losses on the repayment of debt, other non-operating items, and results from discontinued operations. Net realized and unrealized investment gains (losses), which include changes in the fair value of equity securities still held, are excluded for purposes of presenting operating income (loss), as they are, to a certain extent, determined by interest rates, financial markets and the timing of sales. Operating income (loss) also excludes net gains and losses from disposals of businesses, gains and losses related to the repayment of debt, costs to acquire businesses, restructuring costs, the cumulative effect of accounting changes, and certain other items. Operating income (loss) is the sum of the segment income (loss) from: Core Commercial, Specialty, Personal Lines, and Other, after interest expense and income taxes. In reference to one of the company’s four segments, “operating income (loss)” is the segment income (loss) before both interest expense and income taxes. The company also uses “operating income (loss) per diluted (basic) share” (which is after both interest expense and income taxes). Operating income per share is calculated by dividing operating income by the weighted average number of diluted shares of common stock. Operating loss per share is calculated by dividing operating loss by the weighted average number of basic shares of common stock due to antidilution. The company believes that metrics of operating income (loss) and operating income (loss) in relation to its four segments provide investors with a valuable measure of the performance of the company’s continuing businesses because they highlight the portion of net income (loss) attributable to the core operations of the business. Income (loss) from continuing operations is the most directly comparable GAAP measure for operating income (loss) (and operating income (loss) before income taxes) and measures of operating income (loss) that exclude the effects of catastrophe losses and/or prior-year reserve development should not be misconstrued as substitutes for income (loss) from continuing operations or net income (loss) determined in accordance with GAAP. A reconciliation of operating income (loss) to income (loss) from continuing operations and net income (loss) for the relevant periods is included on page 12 of this news release and in the Financial Supplement.

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Operating return on average equity (“ROE”) is a non-GAAP measure. See end note (5) for a detailed explanation of how this measure is calculated. Operating ROE is based on non-GAAP operating income (loss). In addition, the portion of shareholder equity attributed to unrealized appreciation (depreciation) on fixed maturity investments, net of tax, is excluded. The company believes this measure is helpful in that it provides insight to the capital used by, and results of, the continuing business exclusive of interest expense, income taxes, and other non-operating items. These measures should not be misconstrued as substitutes for GAAP ROE, which is based on net income (loss) and shareholders’ equity of the entire company and without adjustments.

The company may provide measures of operating income (loss) and combined ratios that exclude the impact of catastrophe losses (which in all respects include prior accident year catastrophe loss development). A catastrophe is a severe loss, resulting from natural or manmade events including, but is not limited to, hurricanes, tornados, windstorms, earthquakes, hail, severe winter weather, freeze events, fire, explosions, civil unrest and terrorism. Due to the unique characteristics of each catastrophe loss, there is an inherent inability to reasonably estimate the timing or loss amount in advance. The company believes a separate discussion excluding the effects of catastrophe losses is meaningful to understand the underlying trends and variability of earnings, loss and combined ratio results, among others.

Book value per share is total shareholders’ equity divided by the number of common shares outstanding. Book value per share excluding net unrealized gains and losses related to fixed maturity investments, net of tax, is total shareholders’ equity excluding the after-tax effect of unrealized investment gains and losses on fixed maturities and market risk divided by the number of common shares outstanding.

Prior accident year reserve development, which can either be favorable or unfavorable, represents changes in the company’s estimate of costs related to claims from prior years. Calendar year loss and loss adjustment expense (“LAE”) ratios determined in accordance with GAAP, excluding prior accident year reserve development, are sometimes referred to as “current accident year loss ratios.” The company believes a discussion of loss and combined ratios, excluding prior accident year reserve development, is helpful since it provides insight into both estimates of current accident year results and the accuracy of prior-year estimates.

The loss and combined ratios in accordance with GAAP are the most directly comparable GAAP measures for the loss and combined ratios calculated excluding the effects of catastrophe losses and/or prior-year reserve development. The presentation of loss and combined ratios calculated excluding the effects of catastrophe losses and/or prior-year reserve development should not be misconstrued as substitutes for the loss and/or combined ratios determined in accordance with GAAP.

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Endnotes

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