The FTSE 100 currently has nine stocks trading at single-digit price-to-earnings (P/E) ratios. A P/E ratio is a quick way of telling us how much the company is earning compared to the price we pay to buy shares in the company. The metric is many an investor’s first stopping point when seeking the cheap shares that can provide handsome returns.

For context, the FTSE 100 average P/E ratio is around 19 at the moment. The (American) S&P 500 is as high as 29. Therefore, these three Footsie stocks, all with a P/E below 10, could be some of the cheapest shares going.

Airlines

Two of the more curious entrants on the list are airlines International Consolidated Airlines (British Airways et al) and easyJet. The differences in the recent fates of both stocks can be seen in their share prices. IAG is up 38% in the last year, while easyJet is down 15% over the same timeframe. But the presence of both suggests that their inclusion might not be company-specific issues but a sector-wide malaise.

Airlines themselves are quite fragile businesses. We all saw what happened when a coronavirus did the rounds a few years ago. And between enormous fuel expenditure, high wage costs from their massive workforces, and the risk of lower demand when economic times aren’t so good, there’s clearly a lot of risk to think about here.

There’s a reason why Warren Buffett said: “Investors have poured their money into airlines for 100 years with terrible results.”

Still, buying when the chips are down is one way to get an edge in investing. I’d say both stocks are worth considering at their current valuations.

Fashion

Another oddly cheap FTSE 100 stock is JD Sports (LSE: JD.). The athletics retailer is a bona fide growth stock, climbing massively in recent years. A £20k stake bought in 2012 would have turned into £600k by 2022.

Stocks that grow so quickly tend to trade at a premium. A P/E ratio of 30 or higher is not unheard of with this kind of growing company. So the ‘King of Trainers’ is the last stock I’d expect to be trading at a P/E of just 8.4.

What’s going on here? Well, the shares have been on the slide since 2022. A drop of 64% has come with concerns about the cost-of-living, youth unemployment and general doom and gloom about the economy. If young people have less spare cash then the future of JD Sports looks less promising.

There’s a faint chance we might also be seeing a move away from athleisure as a fashion choice. Interestingly, Nike shares are down 63% and Adidas shares are down 48% in the last five years. This is another risk with clothing stocks and is also the reason why I don’t think JD is worth considering for the average investor.

For my money, there are more attractive stocks out there today.