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Exhibit 10.4.8

PERFORMANCE UNIT AWARD AGREEMENT

        THIS AGREEMENT (this "Agreement") is made, effective as of the 1st of
March, 2006, between OneBeacon Insurance Group LLC (the "Company"), and
                        (the "Participant").

RECITALS:

        WHEREAS, the Company has adopted the OneBeacon Performance Unit Plan
(the "Plan"), which Plan is incorporated herein by reference and made part of
this Agreement; and

        WHEREAS, the Committee has delegated to the Board of Managers of the
Company (the "Company Board") the power and authority to grant Awards pursuant
to the Plan and establish the terms of such Awards; and

        WHEREAS, the Company Board has determined that it would be in the best
interests of the Company and its members to grant the Award provided for herein
to the Participant pursuant to the Plan and the terms set forth herein.

        NOW THEREFORE, in consideration of the mutual covenants hereinafter set
forth, the parties hereto agree as follows:

        1.     Grant of the Performance Units.    Subject to the terms and
conditions of the Plan and the additional terms and conditions set forth in this
Agreement, the Company hereby grants to the Participant an Award consisting
of      Performance Units (the "Target Units"). In no event will the Actual
Value of an Actual Unit exceed $171 for any purpose of this Award.

        2.     Award Period/Performance Period.    The Award Period shall be
January 1, 2006 through December 31, 2008. The Award Period contains three
Performance Periods: (a) the first Performance Period shall be calendar year
2006, (b) the second Performance Period shall be calendar year 2007, and (c) the
third Performance Period shall be calendar year 2008.

        3.     Performance Goal.    The Performance Goal applicable to this
Award shall be a GAAP combined ratio for the Company and its subsidiaries (the
"Combined Ratio") of 96% for the Award Period as a whole. The Combined Ratio for
the Award Period as a whole will be computed as the average (mean) of the
Combined Ratio for each of the three constituent Performance Periods. The Board
shall decide in its sole discretion whether and to what extent the Performance
Goal has been achieved.

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        4.     Performance Percentage.    The Performance Percentage applicable
to the Target Units shall be dependent upon the extent to which the Performance
Goal set forth in Section 3 is achieved and shall be determined as follows:

Combined Ratio For the Award Period

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  Performance
Percentage

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    102% or higher   0 %   101%   23 %   100%   43.5 %   99%   61.5 %   98%   77
%   97%   90 %   96%   100 %   95%   110 %   94%   123 %   93%   138.5 %   92%  
156.5 %   91%   177 %   90% or lower   200 %

        Combined Ratios are calculated to the nearest one-tenth percentage
point. In the event the Combined Ratio for the Award Period is not a whole
percentage value, the Performance Percentage shall be determined by
straight-line interpolation between the two successive whole Combined Ratio
values from the table above.

        5.     Termination of Employment.    Except as provided in this
Agreement or in Section 8 of the Plan, this Award shall be canceled, and no
payment shall be payable hereunder, if the Participant's continuous employment
or Related Employment with the Company shall terminate for any reason prior to
the end of the Award Period.

a.If, while actively employed by the Company or its Affiliates, the Participant
dies or becomes Disabled prior to the end of the Award Period, this Award shall
be canceled at the end of the Performance Period in which such event occurs and
the Participant shall be entitled to receive the Earned Payment calculated as
follows:

•The number of Target Units shall be adjusted to equal (i) the number of Target
Units granted in Section 1 multiplied by (ii) a fraction equal to the number of
full or partial months of actual service during the Award Period through the
date the Participant dies or becomes Disabled divided by 36 (the "Adjusted
Target Units");

•The Performance Percentage applicable to the Adjusted Target Units shall be
determined as provided in Section 4 based on the achievement of the Performance
Goal through the end of the Performance Period in which the Participant dies or
becomes Disabled; provided that the Performance Percentage applicable to the
Adjusted Target Units shall not be less than 50%; and

•The Actual Value of the Actual Units determined hereunder shall be based upon
the aggregate standard after-tax underwriting return on capital of the Company
and its subsidiaries over the portion of the Award Period ending on the last day
of the Performance Period in which the Participant dies or becomes Disabled.

Payment of the Participant's Earned Payment shall be made in cash as soon as
practicable following the Performance Period in which the Participant dies or
becomes Disabled.

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b.If, while actively employed by the Company or its Affiliates, the Participant
retires on or after his 60th birthday by mutual agreement with the Company prior
to the end of the Award Period, this Award shall be cancelled at the end of the
Performance Period in which the retirement occurs and the Participant shall be
entitled to receive the Earned Payment calculated as follows:

•The number of Target Units shall be adjusted to equal: (i) the number of Target
Units granted in Section 1 multiplied by (ii) a fraction equal to the number of
full or partial months of actual service during the Award Period through the
date the Participant retires hereunder divided by 36 (the "Adjusted Target
Units");

•The Performance Percentage applicable to the Adjusted Target Units shall be
determined as provided in Section 4 above based on the achievement of the
Performance Goal through the end of the Performance Period in which the
Participant retires hereunder; and

•The Actual Value of the Actual Units determined hereunder shall be based upon
the aggregate standard after-tax underwriting return on capital of the Company
and its subsidiaries over the portion of the Award Period ending on the last day
of the Performance Period in which the Participant retires hereunder;

Payment of the Participant's Earned Payment shall be made in cash as soon as
practicable following the Performance Period in which the Participant retires
hereunder.

        6.     Payment of Award.    Except as provided elsewhere in Section 5 or
Section 8 of the Plan, as soon as practicable after the end of the Award Period,
or such earlier date as the Company Board in its sole discretion may determine,
the Company Board shall determine the Participant's Earned Payment for the Award
Period by determining the number of Actual Units earned by the Participant and
the Actual Value of each such Actual Unit. Payment of any Earned Payment shall
be made by the Company as promptly as practicable or deferred to such other time
or times as the Committee shall determine.

        7.     Successor Requirement.    This Agreement shall inure to the
benefit of and be binding upon the Company and its successors and assigns. The
Company shall require any purchaser of substantially all of the business unit in
which the Participant is employed (a "Purchaser"), to fully assume the
obligations of the Company under this Agreement. If a Purchaser declines to
assume such obligations, the Company shall remain obligated under the terms of
this Agreement.

        8.     Definitions.    Capitalized terms not otherwise defined herein
shall have the same meanings as in the Plan. The following capitalized terms
used in this Agreement have the respective meanings set forth in this Section.

a)Actual Value.    The value of each Actual Unit determined by multiplying the
Initial Value by the sum of (i) 100% and (ii) the aggregate after-tax
Underwriting Return on Capital (UROC) of the Company and its subsidiaries over
the Award Period, as determined in good faith by the Committee. By way of
example, if the standard after tax underwriting return on capital of the Company
were to be 13.0% for each year in a three-year Award Period, the aggregate
standard after—tax underwriting return on capital of the Company and its
subsidiaries over the Award Period would be 44.3% (i.e., 13.0% compounded
annually in each of the three years comprising the Award Period) and the Actual
Value of each Actual Unit would be $144 (i.e., $100 × 144%).

b)Disabled.    The Participant shall be deemed to be Disabled if the Company
Board shall determine that the Participant would be eligible for monthly
benefits under the Company's (or any subsidiary's applicable) long-term
disability

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c)Related Employment.    For purposes of this Agreement, Related Employment
shall mean the employment of the Participant by an employer who is not the
Company or an Affiliate of the Company, provided (i) such employment is
undertaken by the Participant and continued at the request of the Company;
(ii) immediately prior to undertaking such employment, the Participant was an
employee of the Company, or any of its Subsidiaries, or was engaged in Related
Employment; and (iii) such employment is recognized by the Company Board, in its
sole discretion, as Related Employment for purposes of this Agreement.

        9.     Withholding.    The Participant agrees to make appropriate
arrangements with the Company for satisfaction of any applicable federal, state,
local or foreign income tax withholding requirements or like requirements,
including the payment to the Company, at the termination of the Award Period (or
such earlier or later date as may be applicable under Section 83 of the Code),
or at any other settlement date in respect of the Performance Units, of all such
taxes and other amounts and the Company shall be authorized to take such action
as may be necessary, in the opinion of the Company's counsel (including, without
limitation, withholding amounts from any compensation or other amount owing from
the Company to the Participant), to satisfy all obligations for the payment of
such taxes and other amounts.

        10.   Reduction of the Award.    Notwithstanding anything to the
contrary herein, the Company Board, in its sole discretion (but subject to
applicable law), may reduce any amounts payable to the Participant in order to
satisfy any liabilities owed to the Company by the Participant.

        11.   No Right to Continued Employment.    Neither the Plan nor this
Agreement shall be construed as giving the Participant the right to be retained
in the employ of, or in any consulting relationship to, the Company or any of
its subsidiaries. Further, the Company or any of its subsidiaries may at any
time dismiss the Participant or discontinue any consulting relationship, free
from any liability or any claim under the Plan or this Agreement, except as
otherwise expressly provided herein. In addition, nothing herein shall obligate
the Company to grant future Awards to the Participant.

        12.   Award Subject to Plan.    By entering into this Agreement the
Participant agrees and acknowledges that the Participant has received and read a
copy of the Plan and that this Award is subject to all of the terms and
provisions set forth therein. In the event of a conflict between any term or
provision contained herein and a term or provision of the Plan, the applicable
terms and provisions of the Plan will govern and prevail.

        13.   Designation of Beneficiary by Participant.    A Participant may
name a beneficiary to receive any payment to which he may be entitled in respect
of this Award in the event of his death, on a form to be provided by the Company
Board. A Participant may change his beneficiary from time to time in the same
manner. If no designated beneficiary is living on the date on which any amount
becomes payable to a Participant's executors or administrators, the term
"beneficiary" as used in this Agreement shall include such person or persons.

        14.   Notices.    Any notice necessary under this Agreement shall be
addressed to the Company in care of the Secretary at the principal executive
office of the Company and to the Participant at the address appearing in the
personnel records of the Company for such Participant or to either party at such
other address as such party hereto may hereafter designate in writing to the
other. Any such notice shall be deemed effective upon receipt thereof by the
addressee.

        15.   Signature in Counterparts.    This Agreement may be signed in
counterparts, each of which shall be an original, with the same effect as if the
signatures thereto and hereto were upon the same instrument.

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        IN WITNESS WHEREOF, the parties hereto have executed this Agreement.

Participant     OneBeacon Insurance Group LLC
    

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Name:
 
By:
/s/  MIKE MILLER      

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Name: Mike Miller
Title: President & CEO

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Date
 
 
 
Awards Details:
 
 
 

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Exhibit 10.4.8