Over the last week, NatWest (LSE: NWG) shares have been in demand. The FTSE 100 bank is the most bought stock on the AJ Bell investment platform. It’s even outstripped growth superheroes Rolls-Royce and Nvidia, languishing in seventh and eighth place. Why the sudden explosion in popularity?

I might be in a position to explain, because I’ve been buying NatWest shares too. And no, I wasn’t following the herd. I made that decision all on my own. Unusually for me, it was a split-second decision too. No dithering.

Is this FTSE 100 bank a brilliant bargain?

The date was 1 May. NatWest had just posted Q1 results. At first glance, they looked decent enough, with profits climbing 12%. The board even raised 2026 income guidance. But markets chose to fret over revenue growth, impairment charges and the slowing UK economy. The shares fell 4.5%. I saw my chance to grab them at a cut price, and took it.

This is something I’d wanted to do for months. Like the rest of the FTSE 100 banks, NatWest shares have been bombing along in recent years. Despite that one-day dip, they’re still up 185% over five years, thanks to a steady climb in profits. Check this out:

• 2025 – £7.7bn
• 2024 – £6.2bn
• 2023 – £5.6bn
• 2022 – £5.1bn
• 2021 – £3.8bn

Yet suddenly, this blue-chip profit machine was trading on a dirt-cheap price-to-earnings ratio of 7.7, with a forecast yield of 6.57%. How could I resist? And that’s why I reckon investors are chasing NatWest shares. Because they look like a cracking bargain, with a fantastic rate of income attached.

Those two stellar numbers have eased slightly since then. The forward P/E has crept up to 8.1, while the 2026 forecast yield has slipped to 6.32%. That simply reflects a modest share price rise of around 2.7% since results day. I should maybe point out that all of the big banks still trade on relatively low forward valuations today:

• Barclays – 7.9
• HSBC Holdings – 10.5
• Lloyds Banking Group – 10.3
• NatWest – 8.1

So is NatWest a stone-cold, no-argument buy? Let’s calm down a little, because there are always issues to take into account when buying shares.

Are there risks to buying this stock today?

NatWest remains heavily exposed to the UK economy. If inflation and unemployment keep rising, mortgage demand could fall and default rise. Profits could be squeezed.

There’s also the risk of fresh windfall taxes on the banking sector. Voters still haven’t forgiven the banks for the financial crisis, and politicians are short of cash. And here’s another concern. Bond yields are rising, which means investors can get a higher rate of income, without putting their capital at risk by purchasing shares. That could hit demand for dividend stocks.

Personally, I’m not expecting the NatWest share price to resume its explosive momentum. Growth has clearly slowed lately, with the shares up just 12% over the last 12 months. But I’m thrilled to have bought NatWest at the price I did, and I can see exactly why investors have been piling in. I’ll be watching its progress closely over the summer and, if volatility strikes again, I may well top up my stake. You might want to keep an eye on it too.