Exhibit 12
**Chief Executive Officer Certification**
I, David V. Murray, Chief Executive Officer, certify that:
1. I have reviewed this annual report on Form 20-F of Commonwealth Bank ofAustralia; 2. Based on my knowledge, this report does not contain any untrue statementof a material fact or omit to state a material fact necessary to make thestatements made, in light of the circumstances under which such statementswere made, not misleading with respect to the period covered by thisreport; 3. Based on my knowledge, the financial statements, and other financialinformation included in this report, fairly present in all materialrespects the financial condition, results of operations and cash flows ofthe company as of, and for, the periods presented in this report; 4. The company’s other certifying officer(s) and I are responsible forestablishing and maintaining disclosure controls and procedures (asdefined in Exchange Act Rules 13a-15(e) and 15d-15(e)) for the company andhave:
 a. Designed such disclosure controls and procedures, or caused suchdisclosure controls and procedures to be designed under oursupervision, to ensure that material information relating to thecompany, including its consolidated subsidiaries, is made known to usby others within those entities, particularly during the period inwhich this report is being prepared;  b. [Omitted pursuant to the guidance of SEC Release No. 33-8238 (June5, 2003)]  c. Evaluated the effectiveness of the company’s disclosure controlsand procedures and presented in this report our conclusions about theeffectiveness of the disclosure controls and procedures, as of the endof the period covered by this report based on such evaluation; and  d. Disclosed in this report any change in the company’s internalcontrol over financial reporting that occurred during the periodcovered by the annual report that has materially affected, or isreasonably likely to materially affect, the company’s internal controlover financial reporting; and
5. The company’s other certifying officer(s) and I have disclosed, based onour most recent evaluation of internal control over financial reporting,to the company’s auditors and the audit committee of the company’s boardof directors (or persons performing the equivalent functions):
 a. All significant deficiencies and material weaknesses in the designor operation of internal control over financial reporting which arereasonably likely to adversely affect the company’s ability to record,process, summarize and report financial information; and  a. Any fraud, whether or not material, that involves management orother employees who have a significant role in the company’s internalcontrol over financial reporting.
Date: 25 November 2004 /s/ David V. MurrayName: David V. MurrayTitle: Managing Director and Chief Executive Officer
 

 

**Chief Financial Officer Certification**
I, Michael Cameron, Chief Financial Officer, certify that:
1. I have reviewed this annual report on Form 20-F of Commonwealth Bank ofAustralia; 2. Based on my knowledge, this report does not contain any untrue statementof a material fact or omit to state a material fact necessary to make thestatements made, in light of the circumstances under which such statementswere made, not misleading with respect to the period covered by thisreport; 3. Based on my knowledge, the financial statements, and other financialinformation included in this report, fairly present in all materialrespects the financial condition, results of operations and cash flows ofthe company as of, and for, the periods presented in this report; 4. The company’s other certifying officer(s) and I are responsible forestablishing and maintaining disclosure controls and procedures (asdefined in Exchange Act Rules 13a-15(e) and 15d-15(e)) for the company andhave:
 a. Designed such disclosure controls and procedures, or caused suchdisclosure controls and procedures to be designed under oursupervision, to ensure that material information relating to thecompany, including its consolidated subsidiaries, is made known to usby others within those entities, particularly during the period inwhich this report is being prepared;  b. [Omitted pursuant to the guidance of SEC Release No. 33-8238 (June5, 2003)]  c. Evaluated the effectiveness of the company’s disclosure controlsand procedures and presented in this report our conclusions about theeffectiveness of the disclosure controls and procedures, as of the endof the period covered by this report based on such evaluation; and  d. Disclosed in this report any change in the company’s internalcontrol over financial reporting that occurred during the periodcovered by the annual report that has materially affected, or isreasonably likely to materially affect, the company’s internal controlover financial reporting; and
5. The company’s other certifying officer(s) and I have disclosed, based onour most recent evaluation of internal control over financial reporting,to the company’s auditors and the audit committee of the company’s boardof directors (or persons performing the equivalent functions):
 a. All significant deficiencies and material weaknesses in the designor operation of internal control over financial reporting which arereasonably likely to adversely affect the company’s ability to record,process, summarize and report financial information; and  b. Any fraud, whether or not material, that involves management orother employees who have a significant role in the company’s internalcontrol over financial reporting.
Date: 25 November 2004 /s/ Michael CameronName: Michael CameronTitle: Chief Financial Officer