2026 has been a noteworthy year for National Australia Bank Ltd (ASX: NAB) shares.
On 25 February, shares in the S&P/ASX 200 Index (ASX: XJO) bank stock closed at a record high of $49.10 apiece. By 11 June, the share price had sunk 27.3% to a one-year closing low of $35.68.
Which would have been an opportune time to buy.
In Tuesday afternoon trade, NAB shares were changing hands for $41.06 each, up 15.1% from the June lows.
And if you owned the big four Aussie banks at market close on 6 May, you'd also have received the 85 cents per share fully franked final NAB dividend. The ASX bank stock trades on a 4.5% fully franked trailing dividend yield.
Looking ahead, however, Bell Potter Securities' Christopher Watt forecasts growing headwinds for the big four bank (courtesy of The Bull).
Here's why.

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Time to cash out of NAB shares?
"This tier-1 bank is showing resilient volume growth despite an uncertain environment," Watt said.
Commenting on the bank's recent performance, he noted:
Business and private banking lending balances increased 4% in the June quarter when compared to the March quarter. The value of home lending applications was down 9% quarter-on-quarter.
The stock has performed strongly since June 11 when it was priced at $35.68.
Summarising his sell recommendation on NAB shares, Watt concluded:
However, NAB has above average exposure to business banking compared to competitors, leaving it more exposed to any downturn in a slowing business economy. Investors may want to consider taking a profit.
What's the latest from the ASX 200 bank stock?
NAB reported its half year results (H1 FY 2026) on 4 May.
Highlights for the six months included cash earnings (excluding notable items) of $3.59 billion, up 2.3% year-on-year. And on the bottom line, the bank reported a 6.4% increase in underlying profit.
However, investors sent NAB shares down 1.6% on the day of the results release, partly driven by a $300 million increase in the bank's collective provisions.
Commenting on that increase, NAB CEO Andrew Irvine noted:
Geopolitical tensions have created a more volatile macro-economic environment. We enter this period in good shape and actions taken in 1H26 to bolster our balance sheet will allow us to continue to grow and support customers.
Forward looking collective provisions (CP) have increased by $300 million and the ratio of CP to credit risk-weighted assets sits at 1.35%.
NAB shares will be ones to keep an eye on next Monday, 17 August, when the bank releases its third-quarter trading update.