After a strong multi year climb, with Delta Air Lines stock delivering a 105.6% total return over 5 years, investors now have to weigh that track record against a valuation picture that looks neither clearly cheap nor clearly expensive on the broader checks.

• Over the past 5 years Delta Air Lines has returned 105.6%, which puts current holders in profit and raises the bar for what would justify further upside from here.
• Expansion of Delta Air Lines' premium and international network, including new long haul routes such as the planned Austin to Paris service, can support expectations for cash generation, while pressure on margins and any weakness in domestic or corporate travel remain key risks for how much investors are willing to pay.
• On Simply Wall St's broader checks Delta Air Lines scores 4 out of 6 on valuation, which points to a mixed picture rather than a clear bargain or clear overvaluation.

The issue now is whether the current price around US$82.41 offers enough compensation for these risks after such a strong 5 year run in Delta Air Lines stock.

Is Delta Air Lines Still Cheap on Earnings?

The P/E ratio is a useful way to check how much you are paying for each dollar of Delta Air Lines earnings today. Delta trades on a P/E of about 13.6x, which is slightly above the peer average of 13.0x and above the wider airlines industry average of 11.5x.

However, Simply Wall St's fair P/E for Delta Air Lines is 29.8x, which is far higher than where the stock trades now. That fair ratio reflects what investors might pay given the company profile, its premium and international focus, and the risks that come with an airline business. Even with Berkshire Hathaway increasing its stake and keeping attention on the stock, the current P/E still sits well below this fair benchmark.

On this P/E yardstick, Delta Air Lines stock appears undervalued compared with what the tailored fair multiple suggests.

The Delta Air Lines Narrative: What Would Justify Today's Price?

Simply Wall St Narratives for Delta Air Lines pick up where the valuation puzzle leaves off and spell out which paths for Delta Air Lines' revenue, margins and earnings would need to play out for the stock to be worth meaningfully more or less than today. Instead of a single output from a ratio or model, they set out the future that figure relies on so you can see over time whether Delta Air Lines' actual progress lines up with that scenario.

Community views on Delta Air Lines are sharply split, with one camp focused on premium and loyalty strength and the other on thinner margins and macro risks.

Bull case: 22% undervalued

"Delta is capitalizing on resilient revenue streams such as premium, loyalty, and international segments, which are expected to continue growing and thus bolster overall revenue…"

Bear case: 30% overvalued

"Margins are so thin they simply cannot accomodate any major impact, so you got to be vigilant when investing in an airline even as big as this one…"

Do you think there's more to the story for Delta Air Lines? Head over to our Community to see what others are saying!

The Bottom Line

For Delta Air Lines, the main message is that the current P/E points to an undervalued stock when set against the tailored fair multiple, but the broader checks still look mixed rather than clearly one sided. The debate now is whether premium, loyalty and international strengths can keep earnings support firm enough to close that gap, or whether thin margins and macro sensitivity mean the current discount is justified. What matters most from here is how consistently Delta converts its network and brand advantages into resilient profitability without major margin shocks.

This article by Simply Wall St is general in nature. We provide commentary based on historical data and analyst forecasts only using an unbiased methodology and our articles are not intended to be financial advice. It does not constitute a recommendation to buy or sell any stock, and does not take account of your objectives, or your financial situation. We aim to bring you long-term focused analysis driven by fundamental data. Note that our analysis may not factor in the latest price-sensitive company announcements or qualitative material. Simply Wall St has no position in any stocks mentioned.