Fitch Ratings revised the outlook on Commonwealth Bank of Australia's (ASX:CBA) long-term issuer default rating to positive from stable, affirming the rating at AA-, reflecting the bank's continued strong earnings profile, according to a Wednesday release.

It also affirmed the short-term issuer default rating at F1+, the viability rating at a+, and the government support rating at a.

Sustained stronger earnings from the lender could support a higher earnings and profitability score and ultimately an upgrade in the viability rating, the rating firm noted.

The strong earnings indicate better internal capital generation and therefore may also be a positive consideration for its capitalization and leverage assessment.

The bank's operating profit-to-risk-weighted assets ratio is expected to outperform domestic major bank peers, reflecting the bank's strong retail franchise and leading technology platforms. The ratio was 3.1% in the first half of the fiscal year, and it is forecast to remain modestly above 3% through fiscal 2027.

It has a strong capital position and its common equity Tier 1 ratio is forecast to be around 12% through to fiscal 2026, assuming no additional share buybacks, the rating firm said.

The bank's funding and liquidity score was revised to a+ from a to reflect the significant improvement in its funding metrics over more than a decade. Its loan-to-customer deposit ratio is expected to stabilize around current levels, with loan and deposit growth largely matching.

The lender's sound liquidity management and funding plans offset the risk associated with the bank's reliance on offshore wholesale markets for part of its funding, the report added.

CBA accounts for 20% of system assets in Australia's banking ecosystem as of the end of 2024, and it holds about 18% of New Zealand's banking system assets through its subsidiary, ASB Bank.

Its shares fell almost 1% in recent trading on Thursday.