For years, Commonwealth Bank of Australia (ASX: CBA) shares have been the market's favourite comfort stock. Rock-solid brand, dependable dividends and a balance sheet investors trust with their lives.
So far in 2026, the banking giant's shares are down almost 4% and now sit 14.5% below their level of six months ago.
The weakness follows a stellar 2025, when CBA shares staged a powerful rally and surged to a record high of $192.00 in June.
Here are three reasons some investors are quietly heading for the exit.
Overvalued with modest growth
First, the valuation has gone from premium to punchy. CBA shares trade well above their big-four peers on almost every traditional metric. Its price-to-earnings and price-to-book ratios suggest investors are paying luxury-car prices for a stock growing more like a family sedan.
CBA is currently trading at a price-to-earnings (P/E) ratio of 26.68, significantly higher than its major Australian banking peers. By comparison, Westpac Banking Corp (ASX: WBC) trades at a P/E of approximately 19.64, National Australian Bank Ltd (ASX: NAB) at around 19.20, and ANZ Group Holdings Ltd (ASX:ANZ) at about 18.67.
The problem? Banks aren't high-growth tech plays. Earnings growth is modest at best, yet the market continues to price $258 billion CBA as if it deserves a permanent gold star. When expectations are this high, even a small disappointment can trigger an outsized share price reaction.
Squeezed margins, fierce competition
Second, profit margins are under pressure — and that's hard to ignore. Net interest margins, the lifeblood of bank profitability, are being squeezed from all sides. Competition for deposits is fierce, funding costs remain elevated, and political pressure keeps mortgage pricing tight.
While CBA is arguably the best-run bank in the country, it can't escape industry physics. If margins keep narrowing, earnings growth slows and suddenly that premium valuation looks even harder to justify.
Home lending risk
Third, the housing market cuts both ways. CBA's dominance in home lending has long been a strength, but it also creates concentration risk. Australian households are carrying high debt levels, and cost-of-living pressures haven't magically disappeared.
A weaker economic backdrop, rising unemployment or falling house prices could push loan impairments higher. Investors don't need a housing crash to feel pain. Even a mild deterioration in credit quality can dent profits and sentiment.
This doesn't mean CBA is a poor bank. It remains a high-quality business with strong capital, loyal customers and dependable dividends.
What do analysts think?
For long-term investors, the real question may be whether their capital is working hard enough, as other sectors offer better growth, value or income, making the case to trim CBA shares more about opportunity cost than risk.
Most brokers share this sentiment. TradingView data shows that 13 out of 15 analysts have a sell or strong sell rating on CBA shares. The average 12-month target price is $124.90 a piece, which implies a 19% drop at the time of writing.
But some analysts think CBA's share price will plummet even more sharply down to $99.81 per share. That suggests a significant 35% drop over the next 12 months.
