It had 17.7 percent of retail funds under management, up from 15.1 percent a year earlier and annual inforce premiums share of 29.7 percent, down from 30.2 percent.
ASB Kiwisaver, the nation's largest KiwiSaver scheme, lifted funds under management by 31 percent in the 12 months through December.
Net profit fell 2 percent to $365 million. The net interest margin widened by 10 basis points, it said.
The local bank's loan impairment expense doubled to $22 million.
Sydney-based Commonwealth Bank's total cash profit from New Zealand rose 7 percent to $393 million, including $44 million from its Sovereign insurance unit, down from $49 million a year earlier.
The parent company, Australia's biggest lender, lifted first-half profit by 1 percent to A$3.66 billion, helped by gains in retail banking and wealth management. Its net interest margin widened by 4 basis points to 2.1 percent
Earnings from retail banking rose 13 percent to A$1.5 billion and earnings from wealth management profit rose 10 percent to A$334 million, it said today.
Commonwealth Bank's shares last trade at A$65.52 on the ASX and have gained 4.7 percent this year.