UNITED STATES
                       SECURITIES AND EXCHANGE COMMISSION
                             Washington, D.C. 20549

                                    FORM 11-K

(Mark One)

             |X| ANNUAL REPORT PURSUANT TO SECTION 15(d) OF THE
                         SECURITIES EXCHANGE ACT OF 1934
                   For the fiscal year ended December 31, 2004


 

             |_| TRANSITION REPORT PURSUANT TO SECTION 15(d) OF THE
                         SECURITIES EXCHANGE ACT OF 1934
                        For the transition period from to

                           Commission File No. 0-16772

A. Full title of the plan and address of the plan:

                              Peoples Bancorp Inc.
                         138 Putnam Street, P.O. Box 738
                              Marietta, Ohio 45750
                     Attn: The Retirement Planning Committee

B. Name of issuer of the securities held pursuant to the plan and address of its
principal executive office:

                              Peoples Bancorp Inc.
                         138 Putnam Street, P.O. Box 738
                              Marietta, Ohio 45750





                                   SIGNATURES

         The Plan. Pursuant to the requirements of the Securities and Exchange
Act of 1934, the trustees (or other persons who administer the employee benefit
plan) have duly caused this annual report to be signed on its behalf by the
undersigned hereunto duly authorized.

                                       PEOPLES BANCORP INC.
                                       RETIREMENT SAVINGS PLAN


Date: June 15, 2005           By:  /s/ JOHN E. DAKESIAN
                                       --------------------------------------
                                       John E. Dakesian
                                       Chairperson, Retirement Plan Committee



                                       2



                  Peoples Bancorp Inc. Retirement Savings Plan

                              EIN 31-0987416 PN 002

                  Accountants' Report and Financial Statements

                           December 31, 2004 and 2003




                                       3



                  Peoples Bancorp Inc. Retirement Savings Plan
                           December 31, 2004 and 2003



CONTENTS



    Independent Accountants' Report.........................................5



    Financial Statements

        Statements of Net Assets Available for Benefits.....................6

        Statements of Changes in Net Assets Available for Benefits .........7

        Notes to Financial Statements....................................8-12



    Supplemental Schedule

        Schedule H, Line 4i - Schedule of Assets (Held at End of Year).....14





                                       4




                         Independent Accountants' Report



Plan Administrator
Peoples Bancorp Inc. Retirement Savings Plan
Marietta, Ohio


We have audited the accompanying statements of net assets available for benefits
of Peoples Bancorp, Inc. Retirement Savings Plan as of December 31, 2004 and
2003, and the related statements of changes in net assets available for benefits
for the years then ended. These financial statements are the responsibility of
the Plan's management. Our responsibility is to express an opinion on these
financial statements based on our audits.

We conducted our audits in accordance with standards of the Public Company
Accounting Oversight Board (United States). Those standards require that we plan
and perform the audit to obtain reasonable assurance about whether the financial
statements are free of material misstatement. An audit includes examining, on a
test basis, evidence supporting the amounts and disclosures in the financial
statements. An audit also includes assessing the accounting principles used and
significant estimates made by management, as well as evaluating the overall
financial statement presentation. We believe that our audits provide a
reasonable basis for our opinion.

In our opinion, the financial statements referred to above present fairly, in
all material respects, the net assets available for benefits of Peoples Bancorp
Inc. Retirement Savings Plan as of December 31, 2004, and 2003, and the changes
in its net assets available for benefits for the years then ended in conformity
with accounting principles generally accepted in the United States of America.

The accompanying supplemental schedule is presented for the purpose of
additional analysis and is not a required part of the basic financial
statements, but is supplementary information required by the Department of
Labor's Rules and Regulations for Reporting and Disclosure under the Employee
Retirement Income Security Act of 1974. This supplemental schedule is the
responsibility of the Plan's management. The supplemental schedule has been
subjected to the auditing procedures applied in the audits of the basic
financial statements and, in our opinion, is fairly stated, in all material
respects, in relation to the basic financial statements taken as a whole.

BKD, LLP

Cincinnati, Ohio
April 14, 2005

Federal Employer Identification Number:  44-0160260



                                       5








                  Peoples Bancorp Inc. Retirement Savings Plan
                 Statements of Net Assets Available for Benefits
                           December 31, 2004 and 2003

                                              
Assets

                                                    2004              2003
                                                -------------------------------

        Investments, at fair value              $   20,357,273   $   17,812,333

        Accrued interest and dividends                  13,220               --
                                                 -------------    -------------


     Net Assets Available for Benefits          $   20,370,493   $   17,812,333
                                                 =============    =============


See Notes to Financial Statements




                                       6






                  Peoples Bancorp Inc. Retirement Savings Plan
           Statements of Changes in Net Assets Available for Benefits
                     Years Ended December 31, 2004 and 2003




                                                                     2004               2003
                                                               -----------------------------------
    Investment Income
                                                                                         
        Net appreciation in fair value of investments          $        656,142   $      3,231,494
        Interest and dividends                                          350,907            207,104
                                                                ---------------    ---------------

               Net investment income                                  1,007,049          3,438,598
                                                                ---------------    ---------------
    Contributions
        Employer                                                        593,485            479,782
        Participants                                                  1,154,834            961,130
        Rollovers                                                       947,066            274,058
                                                                ---------------    ---------------

                                                                      2,695,385          1,714,970
                                                                ---------------    ---------------

               Total additions                                        3,702,434          5,153,568
                                                                ---------------    ---------------
    Deductions
        Benefits paid to participants                                 1,096,430          1,323,974
        Administrative expenses                                          47,844             44,076
                                                                ---------------    ---------------

               Total deductions                                       1,144,274          1,368,050
                                                                ---------------    ---------------

    Net Increase                                                      2,558,160          3,785,518

    Net Assets Available for Benefits, Beginning of Year             17,812,333         14,026,815
                                                                ---------------    ---------------

    Net Assets Available for Benefits, End of Year             $     20,370,493   $     17,812,333
                                                                ===============    ===============



See Notes to Financial Statements



                                       7




                  Peoples Bancorp Inc. Retirement Savings Plan
                          Notes to Financial Statements
                           December 31, 2004 and 2003


NOTE 1:  DESCRIPTION OF THE PLAN

        The following description of the Plan provides only general information.
        Participants should refer to the Plan Document and Summary Plan
        Description for a more complete description of the Plan's provisions,
        which are available from the plan administrator.


    General
    -------
        The Plan is a defined contribution plan sponsored by Peoples Bancorp
        Inc. (Company) for the benefit of its full-time employees who have at
        least one hour of service and are age 21 or older. The Plan is subject
        to the provisions of the Employee Retirement Income Security Act of 1974
        (ERISA). AMVESCAP National Trust Company is the trustee and serves as
        the custodian of the Plan.


    Contributions
    -------------
        The Plan permits eligible employees through a salary deferral election
        to have the Company make annual contributions of up to 100% of eligible
        compensation. Employee rollover contributions are also permitted. The
        Company makes matching contributions of 100% of the employees' salary
        deferral amounts up to 3% of the employees' compensation and 50% of the
        employees' salary deferral amounts on the next 2% of the employees'
        compensation. Company profit-sharing contributions are discretionary as
        determined by the Company's Board of Directors. Contributions are
        subject to certain limitations. Forfeitures are used to reduce Company
        contributions.


    Participant Investment Account Options
    --------------------------------------
        Investment account options available include various funds. Each
        participant has the option of directing his contributions into any of
        the separate investment accounts and may change the allocation daily.

        The Plan document also includes an automatic deferral feature whereby a
        participant is treated as electing to defer a certain percentage of
        eligible compensation unless the participant made an affirmative
        election otherwise.


    Participant Accounts
    --------------------
        Each participant's account is credited with the participant's
        contribution, the Company's contribution and plan earnings and is
        charged with an allocation of administrative expenses. Allocations are
        based on participant earnings or account balances, as defined. The
        benefits to which a participant is entitled is the benefit that can be
        provided from the participant's vested account.


                                       8




    Vesting
    -------
        Participants are immediately vested in their voluntary contributions and
        the Company's matching contributions plus earnings thereon.


    Payment of Benefits
    -------------------
        Upon termination of service, an employee may elect to receive either a
        lump-sum amount equal to the value of his account or a monthly,
        quarterly, or annual installments over a period of not more than the
        participant's assumed life expectancy.


    Participant Loans
    -----------------
        The Plan document includes provisions authorizing loans from the Plan to
        active eligible participants. Loans are made to any eligible participant
        demonstrating a qualifying need. The minimum amount of a loan shall be
        $1,000. The maximum amount of a participant's loan is determined by the
        available loan balance restricted to the lesser of $50,000 or 50% of the
        participant's vested account balance. All loans are covered by demand
        notes and are repayable over a period not to exceed five years (except
        for loans for the purchase of a principal residence) through payroll
        withholdings unless the participant is paying the loan in full. Interest
        on the loans is based on local prevailing rates as determined by the
        plan administrator.


    Plan Termination
    ----------------
        Although it has not expressed an intention to do so, the Company has the
        right under the Plan to discontinue its contributions at any time and to
        terminate the Plan, subject to the provisions of ERISA. In the event of
        plan termination, participants will become 100% vested in their
        accounts.



NOTE 2:  SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES


    Method of Accounting
    --------------------
        The accompanying financial statements are prepared on the accrual method
        of accounting.


    Use of Estimates
    ----------------
        The preparation of financial statements in conformity with accounting
        principles generally accepted in the United States of America requires
        management to make estimates and assumptions that affect the reported
        amounts of net assets and changes in net assets and disclosure of
        contingent assets and liabilities at the date of the financial
        statements. Actual results could differ from those estimates.


                                       9





    Valuation of Investments and Income Recognition
    -----------------------------------------------
        Quoted market prices, if available, are used to value investments.
        Participant loans are valued at cost, which approximates fair value.

        The investments in Peoples Bancorp Inc. Common Stock has been unitized
        and is comprised of cash and Peoples Bancorp Inc. Common Stock. The Plan
        holds between 3% and 5% of these units in cash in order to provide
        liquidity for timely distributions. At December 31, 2004 and 2003 these
        units are comprised of 282,164 and 286,119 shares of Peoples Bancorp
        Inc. Common Stock and cash of $383,498 and $403,678, respectively.

        Purchases and sales of securities are recorded on a trade-date basis.
        Interest income is recorded on the accrual basis. Dividends are recorded
        on the ex-dividend date.


    Plan Tax Status
    ---------------
        The Plan obtained its latest determination letter on January 30, 2004,
        in which the Internal Revenue Service stated that the Plan and related
        trust, as then designed, were in compliance with the applicable
        requirements of the Internal Revenue Code and therefore not subject to
        tax.


    Payment of Benefits
    -------------------
        Benefit payments to participants are recorded upon distribution.


                                       10




NOTE 3:  INVESTMENTS

        The Plan's investments are held by a bank-administered trust fund. The
        Plan's investments (including investments bought, sold and held during
        the year) appreciated (depreciated) in fair value as follows:





                                                                                              2004
                                                                            ---------------------------------------
                                                                             Net Appreciation
                                                                             (Depreciation) in       Fair Value
                                                                             Fair Value During        at End of
                                                                                   Year                 Year
                                                                            ---------------------------------------
           Investments at fair value as determined by quoted market
              price
               Mutual funds
                                                                                                         
                  Columbia Acorn-Z Fund                                       $        264,234   $      1,920,290*
                  Dodge & Cox Balanced Fund                                            107,495          1,508,424*
                  Other                                                                399,310          4,216,553
               Common/collective trust funds
                  Invesco 500 Index Trust                                              190,166          1,941,182*
                  Invesco Stable Value Trust                                                --          1,575,328*
                  Other                                                                 74,034            777,726
               Peoples Bancorp Inc. common stock units                                (379,097)         8,123,256*
                                                                               ---------------    ---------------

                                                                                       656,142         20,062,759

           Investments at cost which  approximates market
               Participant loans                                                            --            294,514
                                                                               ---------------    ---------------

                  Total investments                                           $        656,142   $     20,357,273
                                                                               ===============    ===============




                                       11








                                                                                             2003
                                                                            --------------------------------------
                                                                              Net Appreciation   
                                                                              (Depreciation) in     Fair Value
                                                                              Fair Value During       at End
                                                                                    Year              of Year
                                                                            --------------------------------------
           Investments at fair value as determined by quoted market
              price
               Mutual funds
                                                                                                         
                  Columbia Acorn-Z Fund                                       $        481,860   $      1,570,910*
                  Dodge & Cox Balanced Fund                                            158,959          1,040,240*
                  Other                                                                536,459          2,449,629
               Common/collective trust funds
                  Invesco 500 Index Trust                                              367,584          1,652,648*
                  Invesco Stable Value Trust                                                --          1,415,195*
                  Other                                                                 73,572            601,966
               Peoples Bancorp Inc. common stock units                               1,613,060          8,847,049*
                                                                               ---------------    ---------------

                                                                                     3,231,494         17,577,637

           Investments at cost which  approximates market
               Participant loans                                                            --            234,696
                                                                               ---------------    ---------------

                  Total investments                                           $      3,231,494   $     17,812,333
                                                                               ===============    ===============



        Investments that represented 5% or more of the Plan's assets are
        separately identified (*) above.

        Interest and dividends realized on the Plan's investments for the years
        ended 2004 and 2003 were $350,907 and $207,104, respectively.



NOTE 4:  PARTY-IN-INTEREST TRANSACTIONS

        Party-in-interest transactions include those with fiduciaries or
        employees of the Plan, any person who provides services to the Plan, an
        employer whose employees are covered by the Plan, an employee
        organization whose members are covered by the Plan, a person who owns 50
        percent or more of such employer or employee association, or relatives
        of such persons.

        The Plan holds common stock of Peoples Bancorp Inc., which is the plan
        sponsor. The Plan also invests in certain funds of the Plan trustee. The
        Plan paid $47,844 and $44,076 of recordkeeping fees to AMVESCAP National
        Trust Company during 2004 and 2003 respectively. The Company provides 
        certain administrative services at no cost to the plan.

                                       12





                              Supplemental Schedule





                                       13



                  Peoples Bancorp Inc. Retirement Savings Plan
                              EIN 31-0987416 PN 002
         Schedule H, Line 4i - Schedule of Assets (Held at End of Year)
                                December 31, 2004



 

              Identity of Issuer                         Description of Investment                    Cost          Current Value
-----------------------------------------------------------------------------------------------------------------------------------
                                                                                                                   
American Century Strategic Allocation                                
   Conservative Fund                              15,663 Units;      $5.59 Per Unit             $      84,513     $         87,555
American Century Strategic Allocation
   Moderate Fund                                  16,659 Units;      $6.77 Per Unit                    99,946              112,786
American Century Strategic Allocation
   Aggressive Fund                                19,067 Units;      $7.71 Per Unit                   126,493              147,005
Columbia Acorn-Z Fund                             72,601 Units;     $26.45 Per Unit                 1,273,581            1,920,290
*Invesco 500 Index Trust                          62,558 Units;     $31.03 Per Unit                 1,453,904            1,941,182
*Invesco Structured Small Cap Value Equity
   Trust                                           3,271 Units;    $100.76 Per Unit                   233,436              329,570
*Invesco Core Fixed Income Trust                  14,102 Units;     $31.78 Per Unit                   413,518              448,156
*Invesco Stable Value Trust                    1,575,328 Units;      $1.00 Per Unit                 1,575,328            1,575,328
*Peoples Bancorp Inc. Common
   Stock Units                                   502,988 Units;     $16.15 Per Unit                 3,213,917            8,123,256
American Growth Fund of America                   30,987 Units;     $27.38 Per Unit                   663,007              848,422
Dodge & Cox Common Stock Fund                      7,709 Units;    $130.22 Per Unit                   842,032            1,003,856
Dodge & Cox Balanced Fund                         19,010 Units;     $79.35 Per Unit                 1,267,002            1,508,424
ING Pilgrim International Value Fund              53,506 Units;     $17.65 Per Unit                   692,811              944,383
AIM Mid Cap Core Equity Fund                      25,609 Units;     $28.64 Per Unit                   606,992              733,449
Royce Low-Priced Stock Fund                        4,285 Units;     $15.00 Per Unit                    61,757               65,690
Fidelity Advisor Mid Cap - T Fund                 10,841 Units;     $25.22 Per Unit                   246,144              273,407
Participant loans                                Interest rates ranging from 5.75% to 11.50%                               294,514
                                                                                                 -------------      ---------------

                                                                                                 $  12,854,381      $   20,357,273
                                                                                                 =============      ===============

*Parties-in-interest



                                       14



                               INDEX TO EXHIBITS


EXHIBIT NUMBER                  DESCRIPTION
--------------                  ----------------------------------
23.1                            Consent of Independent Accountants



                                       15