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SECURITIES AND EXCHANGE COMMISSION
WASHINGTON, D.C. 20549


FORM 11-K

(Mark One)


ý

ANNUAL REPORT PURSUANT TO SECTION 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934

For the fiscal year ended December 31, 2001

or

o TRANSITION REPORT PURSUANT TO SECTION 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934

For the transition period from                              to                             

Commission file number 1-15399


A.
Full title of the plan and the address of the plan, if different from that of the issuer named below:

Packaging Corporation of America
Retirement Savings Plan for Salaried Employees

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

Packaging Corporation of America
1900 West Field Court
Lake Forest, IL 60045





Packaging Corporation of America
Retirement Savings Plan for Salaried Employees

 
  Page
A.    Financial Statements    
  Report of Independent Auditors   1
  Financial Statements:    
  Statements of Assets Available for Benefits   2
  Statements of Changes in Assets Available for Benefits   3
  Notes to Financial Statements   4
B.    Exhibits    
  Item 23 Consent of Independent Auditors    

Report of Independent Auditors

Benefits Administration Committee
Packaging Corporation of America
    Retirement Savings Plan for Salaried Employees

We have audited the accompanying Statements of Assets Available for Benefits of the Packaging Corporation of America Retirement Savings Plan for Salaried Employees as of December 31, 2001 and 2000, and the related Statements of Changes in Assets Available for Benefits for the year ended December 31, 2001 and the period from February 1, 2000, date of inception, to December 31, 2000. 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 auditing standards generally accepted in the 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 assets available for benefits of the Plan at December 31, 2001 and 2000, and the changes in its assets available for benefits for the year ended December 31, 2001 and the period from February 1, 2000 to December 31, 2000, in conformity with accounting standards generally accepted in the United States.

Ernst & Young LLP

Chicago, Illinois
May 8, 2002

1



Packaging Corporation of America
Retirement Savings Plan for Salaried Employees


Statements of Assets Available for Benefits

 
  December 31,
 
  2001
  2000
Assets            
Interest in Master Trust   $ 108,503,924   $ 108,275,308
Contributions receivable:            
  Company     191,656     182,672
  Participant     298,179     283,898
  Receivable from Trustee     34,980    
   
 
Assets available for benefits   $ 109,028,739   $ 108,741,878
   
 

See accompanying notes.

2



Packaging Corporation of America
Retirement Savings Plan for Salaried Employees


Statements of Changes in Assets Available for Benefits

 
  Year
Ended
Dec. 31, 2001

  Period from
Feb. 1, 2000
Through
Dec. 31, 2000

 
Additions              
Contributions:              
  Company   $ 5,221,297   $ 4,366,865  
  Participants     8,117,011     6,847,088  
  Rollover     58,524     127,285  
Net investment loss from Master Trust     (5,954,387 )   (2,474,900 )
   
 
 
Total additions     7,442,445     8,866,338  

Deductions

 

 

 

 

 

 

 
Adminstrative expenses     136,249     129,939  
Benefit payments     7,019,335     6,223,184  
   
 
 
Total deductions     7,155,584     6,353,123  
Transfer of assets from Pactiv Corporation Thrift Plan         106,228,663  
   
 
 
Net increase     286,861     108,741,878  
Assets available for benefits at beginning of period     108,741,878      
   
 
 

Assets available for benefits at end of period

 

$

109,028,739

 

$

108,741,878

 
   
 
 

See accompanying notes.

3



Packaging Corporation of America
Retirement Savings Plan for Salaried Employees
Notes to Financial Statements
December 31, 2001

1.    Description of the Plan

        The following description of the Packaging Corporation of America (the Company or PCA) Retirement Saving Plan for Salaried Employees (the Plan) provides only general information. Participants should refer to the Summary Plan Description for a more complete description of the Plan's provisions.

General

        The Plan is a defined-contribution plan, established February 1, 2000, and is subject to the provisions of the Employee Retirement Income Security Act of 1974 (ERISA), as amended. The Plan covers salaried employees of the Company and each of its domestic subsidiaries that have adopted the Plan, who have completed six months of service, as defined. Assets of $106,228,663 were transferred from the Pactiv Corporation Thrift Plan on February 1, 2000. Pactiv Corporation owned the predecessor company to Packaging Corporation of America prior to April 12, 1999.

Contributions

        Upon enrolling in the Plan, participants may contribute between 1% and 16% of pretax annual compensation, as defined, with such contributions limited to $10,500 for years 2001 and 2000. Participants may also rollover qualifying distributions from other qualified plans.

        The Company matches participant pre-tax contributions on the following basis:

        The Company does not match pre-tax contributions in excess of 8% of eligible pay. All Company matching contributions are invested in the PCA Common Stock Fund. Participants may not transfer or withdraw the value of PCA Common Stock purchased with Company matching contributions until attainment of age 55, or upon termination of employment and subsequent request for final distribution or rollover.

        Employees hired by the Company after April 12, 1999, who have completed one year of service, receive an additional retirement savings contribution equal to 2% of eligible pay, as defined. The contribution will be made on behalf of the employee regardless of whether or not the employee is contributing to the Plan. The Company retirement savings contribution is invested in the same proportion as the employee pre-tax investment elections.

Participant Accounts

        Each participant's account is credited with the participant's contributions, Company contributions, and an allocation of Plan earnings/(loss). Allocations are based on account balances, as defined. The benefit to which a participant is entitled is the benefit that can be provided from the participant's account.

Vesting

        Participants are immediately 100% vested in the value of their pre-tax, rollover and matching contributions.

4



        The retirement savings contribution becomes 100% vested upon completion of 5 years of service or upon reaching 65 years of age, permanent disability or death while employed by the Company. Forfeited balances of nonvested terminated participants will be applied to reduce future Company contributions.

Investment Options

        Participants may elect to invest their account balances, except for the matching contributions and related earnings, in any of the available investment options provided by the Plan. The matching contributions and related earnings are invested in the PCA common stock fund.

        Participants may change their investment options on any business day.

Benefit Payments

        In the event of retirement (as defined), death, permanent disability, or termination of employment, the vested balance in the participant's account will be distributed to the participant or the participant's beneficiary in a single lump-sum cash payment. The portion of the participant's account invested in the PCA common stock fund shall be distributed in kind. In-service withdrawals of rollover contributions and related earnings are available for any reason. In-service withdrawals of certain predecessor plan account balances, as defined, are available for any reason. Participants age 55 or older may withdraw the entire value, or any portion thereof, of their Company matching contributions and related savings at any time. Participants age 591/2 or older may withdraw the entire value, or any portion thereof, of their Plan account balance at any time.

Administrative Expenses

        Administrative expenses are paid from Plan assets, to the extent not paid by the Company.

Participant Loans

        A participant may borrow an amount up to the lesser of $50,000 or 50% of their vested account balance. The minimum loan amount is $1,000. Such loans, which are payable over a term specified by the Plan, bear interest at the prime rate as published by the Wall Street Journal and are secured by a participant's account balance in the Plan. Loans must be repaid within 54 months with principal and interest payments made through payroll deductions.

Plan Termination

        Although it has not expressed any intent 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.

2.    Significant Accounting Policies

Investment Valuation and Income Recognition

        The Plan's beneficial interest in the PCA Master Trust (Master Trust) represents the Plan's share of the Master Trust's investments stated at fair value. Securities traded on a national securities exchange are valued at the last reported sales price on the last business day of the plan year; investments traded in the over-the-counter market and listed securities for which no sale was reported on that date are valued at the average of the last reported bid and ask prices. The fair value of participation units owned by the Master Trust in the common collective trust fund and the fair value of the commingled fund were based on quoted redemption value on the last business day of the Plan's fiscal year. Participant loans are stated at cost, which approximates fair value.

5



        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.

Contributions

        Participant contributions are made through payroll deductions and recorded in the period the deductions are made. Company contributions are deposited as soon as administratively practicable after each pay period.

Use of Estimates

        The preparation of financial statements in conformity with accounting principles generally accepted in the United States requires the Plan Administrator to make estimates and assumptions that affect the amounts reported in the financial statements and accompanying notes. Actual results could differ from those estimates.

3.    Master Trust

        The Master Trust includes assets of the Plan and the Packaging Corporation of America Thrift Plan for Hourly Employees. The Plan's investment in the Master Trust is stated at the Plan's equity in the net assets of the Master Trust at December 31, 2001 and 2000.

        The following table presents the fair value of investments for the Master Trust:

 
  December 31,
 
 
  2001
  2000
 
Assets              
Mutual funds   $ 78,248,470   $ 95,369,344  
Common collective trust fund     52,987,609     44,829,431  
Common stock     24,666,212     16,428,871  
Commingled fund     13,037,137     15,166,171  
Participant loans     3,511,325     2,735,966  
   
 
 
    $ 172,450,753   $ 174,529,783  
   
 
 
Plan's percentage interest in Master Trust at December 31, 2001 and 2000     62.92 %   62.04 %
   
 
 

        Mutual fund securities are comprised of investments in the following funds: PIMCO Total Return, Washington Mutual, Europacific Growth, Founders Discovery, INVESCO Total Return, and Fidelity Growth Company. The common stock funds are invested in PCA, Pactiv and Tenneco Automotive stock. The common collective trust fund is invested in PRIMCO IRT Stable Fund. The commingled fund is invested in the BGI Equity Index Fund.

        Investment income is allocated to each participating plan in the Master Trust at the end of each month. The allocation is based on each plan's individual interest in the Master Trust.

6



        Investment income (loss) for the Master Trust was as follows:

 
  Year Ended
December 31, 2001

  February 1,
2000 to
December 31,
2000

 
Interest   $ 3,257,774   $ 2,811,610  
Dividends     1,199,158     7,247,442  
Net realized and unrealized appreciation (depreciation) in fair value of:              
  Mutual funds     (20,150,367 )   (16,058,901 )
  Common stock     4,837,015     357,436  
  Commingled fund     (1,883,742 )   (756,992 )
   
 
 
Total investment loss   $ (12,740,162 ) $ (6,399,405 )
   
 
 

4.    Nonparticipant Directed Investments

        Information about the assets and the significant components of the changes in assets relating to the PCA common stock fund (included in the Master Trust), which includes participant directed and nonparticipant directed investments, is as follows:

 
  December 31,
 
  2001
  2000
Assets:            
  Interest in the PCA common stock fund   $ 12,421,287   $ 6,411,044
    Contributions receivable:            
  Company     179,065     176,977
  Participant     11,466     7,722
   
 
Total assets   $ 12,611,818   $ 6,595,743
   
 
 
  Year Ended
December 31, 2001

  February 1,
2000 to
December 31,
2000

 
Changes in assets:              
Contributions:              
  Company   $ 4,975,396   $ 3,404,904  
  Participant     284,058     74,320  
  Rollovers     3,863     61,629  
  Interest and dividend income     11,518     7,125  
  Net realized and unrealized appreciation in fair value of investments     1,419,135     1,723,659  
  Interfund transfers     (177,173 )   (63,426 )
  Benefits paid     (307,784 )   (36,663 )
  Administrative expenses     (23,078 )   (4,314 )
  Transfers to other investment accounts     (169,860 )   1,428,509  
   
 
 
Net increase in net assets     6,016,075     6,595,743  
Net assets at beginning of period     6,595,743      
   
 
 
Net assets at end of period   $ 12,611,818   $ 6,595,743  
   
 
 

5.    Tax Status

        The Plan has received a favorable determination letter dated May 9, 2001 from the Internal Revenue Service stating that the Plan is qualified under Section 401(a) of the Internal Revenue Code (the Code) and, therefore, the related trust is exempt from taxation. Once qualified, the Plan is required to operate in conformity with the Code to maintain its qualification. The Plan Administrator believes the Plan is being operated in compliance with the applicable requirements of the Code and, therefore, believes that the Plan is qualified and the related trust is tax-exempt.

7



SIGNATURES

        The Plan.    Pursuant to the requirements of the Securities Exchange Act of 1934, the Benefits Administration Committee of Packaging Corporation of America has duly caused this annual report to be signed on its behalf by the undersigned hereunto duly authorized.

    Packaging Corporation of America
Retirement Savings Plan for Salaried Employees
(Name of Plan)

Date: June 28, 2002

        /s/  ANDREA L. DAVEY      
Andrea L. Davey
Vice President—Human Resources

8



INDEX TO EXHIBIT

Exhibit
Number

  Description
23   Consent of Independent Auditors



QuickLinks

Packaging Corporation of America Retirement Savings Plan for Salaried Employees
Packaging Corporation of America Retirement Savings Plan for Salaried Employees Statements of Assets Available for Benefits
Packaging Corporation of America Retirement Savings Plan for Salaried Employees Statements of Changes in Assets Available for Benefits
Packaging Corporation of America Retirement Savings Plan for Salaried Employees Notes to Financial Statements December 31, 2001
SIGNATURES
INDEX TO EXHIBIT

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Exhibit 23


CONSENT OF INDEPENDENT AUDITORS

        We consent to the incorporation by reference in the Registration Statement (Form S-8 No. 333-33176) pertaining to the Packaging Corporation of America Thrift Plan for Hourly Employees, Packaging Corporation of America Retirement Savings Plan for Salaried Employees and Packaging Corporation of America 1999 Long-Term Equity Incentive Plan of our report dated May 8, 2002, with respect to the financial statements of the Packaging Corporation of America Retirement Savings Plan for Salaried Employees included in this Annual Report (Form 11-K) for the year ended December 31, 2001.

Ernst & Young LLP

Chicago, Illinois
June 26, 2002




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CONSENT OF INDEPENDENT AUDITORS