Quest Diagnostics stock has delivered a 79.9% return over the past three years, and the key question now is whether that strong run is still supported by the current valuation. The Discounted Cash Flow (DCF) intrinsic value estimate points to a sizeable gap to the share price, while the broader market multiples suggest the stock is closer to fairly priced.

• Over the past three years Quest Diagnostics has returned 79.9%, which puts the recent share price firmly in focus for anyone reassessing entry or exit levels.
• Recent news highlighting growth in advanced diagnostic services and new testing areas can support expectations for future cash flows, but any slowdown in these higher value segments may weigh on how much investors are willing to pay for those earnings.
• Quest Diagnostics screens as undervalued in 5 of 6 valuation checks, which means the broader set of metrics leans cheap rather than fully pricing in the past share price gains.

The issue now is whether the current price still leaves enough upside relative to the intrinsic value estimate to justify that three year rally.

Is Quest Diagnostics Still Cheap on Cash Flow?

The Discounted Cash Flow (DCF) model estimates what Quest Diagnostics is worth today based on projected future cash the business can return to shareholders. On the latest figures, Quest Diagnostics generated about $1.36b in free cash flow over the last twelve months, and the model assumes these cash flows keep growing rather than shrinking over time.

Using those projections, the DCF model points to an intrinsic value of about $365 per share. This implies the stock trades around 37.5% below that estimate and therefore screens as undervalued. Because Quest Diagnostics recently raised its 2026 revenue and EPS guidance, the market reaction to that stronger outlook appears more cautious than the cash flow valuation suggests.

Overall, the Discounted Cash Flow workup indicates Quest Diagnostics stock currently looks undervalued relative to its projected cash generation.

Our Discounted Cash Flow (DCF) analysis suggests Quest Diagnostics is undervalued by 37.5%. Track this in your watchlist or portfolio, or discover 38 more high quality undervalued stocks.

Is Quest Diagnostics Fairly Priced on Earnings?

The P/E ratio is a useful way to gauge how much investors are paying for each dollar of Quest Diagnostics earnings. Right now, Quest Diagnostics trades on a P/E of about 24.7x, which sits just below the Healthcare industry average of roughly 25.5x and well under the peer group average of about 39.0x.

The fair P/E ratio for Quest Diagnostics, based on its sector, size and risk profile, is estimated at about 25.6x, only slightly above the current multiple. That small gap suggests the market is valuing the stock close to what the tailored model would imply, rather than applying a large premium or discount relative to its earnings power.

Based on the P/E multiple, Quest Diagnostics stock appears roughly fairly valued compared with both the industry and its modeled fair ratio.

The Quest Diagnostics Narrative: What Would Justify Today's Price?

Simply Wall St Narratives pick up where the Quest Diagnostics valuation puzzle leaves off by laying out the specific growth, margin and earnings paths that would need to hold for the stock to be worth materially more or less than it is today. These Narratives sit on the company’s Community page. Each Narrative ties a fair value estimate to a particular mix of potential catalysts and risks so you can see over time which version of Quest Diagnostics' story is gaining traction.

Share a narrative on Quest Diagnostics in the Simply Wall St community to lay out your numbers-driven view on whether its raised revenue and EPS guidance really holds up, and then track how that thesis plays out as new results arrive.

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

The Bottom Line

Quest Diagnostics looks undervalued on a Discounted Cash Flow (DCF) view, with the intrinsic value estimate sitting well above the current share price, while the P/E-based read says the stock is priced about right versus peers. That mix suggests the market is giving limited credit for the projected cash flows despite broader valuation checks leaning supportive. The key factor from here is whether Quest Diagnostics can sustain the earnings and cash generation implied in that intrinsic value, particularly in higher value testing segments, or whether the current discount is the market pricing the risk of slower growth.

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.