**EXHIBIT 31(i)**

**Amended Rule 13a-14(a)/15d-14(a) Certification of Mr. William Wrigley Jr.**

| I, William   Wrigley, Jr., Chairman of the Board and Chief Executive Officer of Wm.   Wrigley Jr. Company, certify that: |
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| 1.                                                                                                                       | I have reviewed this annual report on Form 10-K/A of Wm. Wrigley Jr.   Company; |
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| 2.                                                                                                                       | Based on my   knowledge, this report does not contain any untrue statement of a material   fact or omit to state a material fact necessary to make the statements made,   in light of the circumstances under which such statements were made, not   misleading with respect to the period covered by this report; |
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| 3.                                                                                                                       | (Intentionally omitted) |
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| 4.                                                                                                                       | The registrant’s other certifyingofficer and I are responsible for establishing and maintaining disclosurecontrols and procedures (as defined in Exchange Act Rules 13a-15(e) and15d-15(e)) and internal control over financial reporting (as defined in ExchangeAct Rules 13a-15(f) and 15d-15(f)) and have: |
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|                                                                                                                     | (a) | Designed   such disclosure controls and procedures or caused such disclosure controls   and procedures to be designed under our supervision, to ensure that material   information relating to the registrant, including its consolidated   subsidiaries, is made known to us by others within those entities,   particularly during the period in which this report is being prepared; |
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|                                                                                                                     | (b) | Designed   such internal control over financial reporting, or caused such internal   control over financial reporting to be designed under our supervision, to   provide reasonable assurance regarding the reliability of financial reporting   and the preparation of financial statements for external purposes in   accordance with the generally accepted accounting principles; |
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|                                                                                                                     | (c) | Evaluated   the effectiveness of the registrant’s disclosure controls and procedures and   presented in this report our conclusions about the effectiveness of the   disclosure controls and procedures, as of the end of the period covered by   this report based on such evaluation; and |
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|                                                                                                                     | (d) | Disclosed in   this report any change in the registrant’s internal control over financial   reporting that occurred during the registrant’s most recent fiscal quarter   (the registrant’s fourth quarter in the case of an annual report) that has   materially affected, or is reasonably likely to materially affect, the   registrant’s internal control over financial reporting; and; |
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| 5.                                                                                                                       | The   registrant’s other certifying officer and I have disclosed, based on our most   recent evaluation of internal control over financial reporting, to the   registrant’s auditors and the audit committee of registrant’s board of   directors (or persons performing the equivalent functions): |
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|                                                                                                                     |   | (a) | All significant deficiencies and material weaknesses in the design or   operation of internal control over financial reporting which are reasonably   likely to adversely affect the registrant’s ability to record, process,   summarize and report financial information; and |
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|                                                                                                                     |   | (b) | Any fraud, whether or not material, that involves management or other   employees who have a significant role in the registrant’s internal control   over financial reporting. |

 

| Date: February 8, 2005 |                                                                                    |
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|                   | /s/WILLIAM WRIGLEY,   JR.                                                               |
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|                   | William   Wrigley, Jr.   Chairman of the Board, President and   Chief Executive Officer |