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Preliminary Proxy Statement

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Confidential, for Use of the Commission Only (as permitted by Rule 14a‑6(e)(2))

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Definitive Proxy Statement

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Definitive Additional Materials

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Soliciting Material under §240.14a‑12

SAFETY INSURANCE GROUP, INC.

(Name of Registrant as Specified In Its Charter)

(Name of Person(s) Filing Proxy Statement, if other than the Registrant)

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No fee required.

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Fee computed on table below per Exchange Act Rules 14a‑6(i)(1) and 0‑11.

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Fee paid previously with preliminary materials.

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1.

A new Proposal 4 shall be added to the Notice of Annual Meeting of Stockholders and current Proposal 4 shall be renumbered Proposal 5. The new Proposal 4 is a non-binding advisory vote to approve the frequency of stockholder advisory votes on the compensation of our named executive officers. The Notice is amended to read in its entirety as follows:

1.

a proposal to elect one of the Company’s directors to Class III with a term ending in 2020;

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to ratify the appointment of PricewaterhouseCoopers LLP as the Company’s independent

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to provide an advisory vote on the compensation of the named executive officers as disclosed in this Proxy Statement;

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to provide an advisory vote on the frequency of future advisory votes on the compensation of the named executive officers; and

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the transaction of such other business as may properly come before the meeting or any adjournment or adjournments thereof.

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A new paragraph shall be added in between paragraphs 5 and 6 in the Section entitled “General Information” as follows:

3.

A new Proposal 4 of the Proxy Statement, under a section entitled “Advisory Vote on the Frequency of Future Advisory Votes on Execution Compensation” shall be added to the Proxy Statement after the section entitled “Advisory Vote on Executive Compensation (Proposal 3)”. Proposal 4 is added to read in its entirety as follows:

VOTE BY INTERNET - www.proxyvote.com Use the Internet to transmit your voting instructions and for electronic delivery of information up until 11:59 P.M. Eastern Time the day before the meeting date. Have your proxy card in hand when you access the web site and follow the instructions to obtain your records and to create an electronic voting instruction form. SAFETY INSURANCE GROUP, INC. ATTN: JOSEPH A. ALMEIDA 20 CUSTOM HOUSE STREET BOSTON, MA 02210 ELECTRONIC DELIVERY OF FUTURE PROXY MATERIALS If you would like to reduce the costs incurred by our company in mailing proxy materials, you can consent to receiving all future proxy statements, proxy cards and annual reports electronically via e-mail or the Internet. To sign up for electronic delivery, please follow the instructions above to vote using the Internet and, when prompted, indicate that you agree to receive or access proxy materials electronically in future years. VOTE BY PHONE - 1-800-690-6903 Use any touch-tone telephone to transmit your voting instructions up until 11:59 P.M. Eastern Time the day before the meeting date. Have your proxy card in hand when you call and then follow the instructions. VOTE BY MAIL Mark, sign and date your proxy card and return it in the postage-paid envelope we have provided or return it to Vote Processing, c/o Broadridge, 51 Mercedes Way, Edgewood, NY 11717. TO VOTE, MARK BLOCKS BELOW IN BLUE OR BLACK INK AS FOLLOWS: E28558-P86734 KEEP THIS PORTION FOR YOUR RECORDS DETACH AND RETURN THIS PORTION ONLY THIS PROXY CARD IS VALID ONLY WHEN SIGNED AND DATED. SAFETY INSURANCE GROUP, INC. The Board of Directors recommends you vote FOR the following: 1. Election of one Class III Director to serve a three year term expiring in 2020. Nominee: For Withhold ! ! 1a. David F. Brussard For Against Abstain The Board of Directors recommends you vote FOR proposals 2 and 3. ! ! ! ! ! ! 2. Ratification of the Appointment of PRICEWATERHOUSECOOPERS LLP. 3. Advisory Vote on Executive Compensation. The Board of Directors recommends you vote 1 Year on the following proposal: 1 Year 2 Years 3 Years Abstain ! ! ! ! 4. Advisory Vote on the Frequency of Future Advisory Votes on Executive Compensation. NOTE: Such other business as may properly come before the meeting or any adjournment thereof. ! For address changes and/or comments, please check this box and write them on the back where indicated. Please sign exactly as your name(s) appear(s) hereon. When signing as attorney, executor, administrator, or other fiduciary, please give full title as such. Joint owners should each sign personally. All holders must sign. If a corporation or partnership, please sign in full corporate or partnership name by authorized officer. Signature [PLEASE SIGN WITHIN BOX] Date Signature (Joint Owners) Date V.1.1

Important Notice Regarding the Availability of Proxy Materials for the Annual Meeting: The Notice and Proxy Statement and 10-K Wrap are available at www.proxyvote.com. E28559-P86734 SAFETY INSURANCE GROUP, INC. Annual Meeting of Shareholders May 24, 2017 10:00 AM This proxy is solicited by the Board of Directors The shareholder hereby appoint(s) George M. Murphy and William J. Begley, Jr. (each with the power to act without the other and with power of substitution) or either of them, as proxies, each with the power to appoint his substitute, and hereby authorizes them to represent and to vote, as designated on the reverse side of this ballot, all of the shares of common stock of SAFETY INSURANCE GROUP, INC. that the shareholder is entitled to vote at the Annual Meeting of Shareholders to be held at 10:00 AM, EDT on May 24, 2017, at 20 CUSTOM HOUSE STREET, BOSTON, MA 02210, and any adjournment or postponement thereof. This proxy, when properly executed, will be voted in the manner directed herein. If no such direction is made, this proxy will be voted in accordance with the Board of Directors' recommendations. (If you noted any Address Changes/Comments above, please mark corresponding box on the reverse side.) Continued and to be signed on reverse side V.1.1 Address Changes/Comments: