Castle Biosciences (CSTL) opened Q1 2026 with revenue of US$83.7 million and a basic EPS loss of US$0.49, as net income excluding extra items came in at a loss of US$14.5 million. Over recent quarters, the company has seen revenue move between US$83.0 million and US$88.0 million while basic EPS has ranged from a loss of US$0.90 to a profit of US$0.16. This gives investors a clear view of how margins have been stretching and compressing as the business scales.

See our full analysis for Castle Biosciences.

With the headline numbers on the table, the next step is to set these results against the widely followed growth and profitability narratives to see which views hold up and which start to look dated.

Losses Widen Again To US$14.5 Million

• Q1 2026 net income excluding extra items was a loss of US$14.5 million compared with losses between US$0.5 million and US$25.8 million over the previous four quarters, while trailing 12 month losses sat at US$12.8 million on US$339.9 million of revenue.
• Consensus narrative talks up long term growth from a broader test menu and expanding clinical evidence, yet the current trailing 12 month loss and the swing from a US$9.6 million profit in Q4 2024 to successive losses in 2025 and Q1 2026 show that higher spending and reimbursement pressures still weigh on earnings.
  • Analysts who expect revenue growth of 7.9% a year and a move from a 7.0% loss margin to a 5.1% profit margin are effectively assuming that this run of recent quarterly losses is temporary.
  • The need to lift margins from a trailing loss of US$12.8 million to a projected US$22.2 million profit by 2029 is a big step and recent results indicate that this shift is not yet visible in the reported numbers.

Path To Profitability Still Some Distance Away

• On a trailing 12 month basis, Castle Biosciences reported basic EPS of a US$0.44 loss and net income excluding extra items of a US$12.8 million loss, even though losses have been reduced over the past five years at an annualized rate of 21.5% according to the analysis summary.
• Bulls point to forecast earnings growth of about 50.5% a year and an expectation that the company becomes profitable within three years, but the current loss profile highlights how much needs to change for that scenario to play out.
  • The bullish view leans heavily on newer tests like AdvanceAD Tx and wider use of DecisionDx and TissueCypher, while Q1 2026 results still show the business operating at a loss of US$14.5 million despite revenue around the mid US$80 million range.
  • Forecasts that earnings could reach roughly US$23.0 million by around 2029 from a loss of US$12.2 million today assume margin gains that are not yet reflected in the recent quarterly EPS range from a US$0.90 loss to a US$0.16 profit.

On these numbers, bulls are banking on new tests and margin gains to outweigh today’s losses, so it can be helpful to see how that full story is laid out in one place before deciding if you agree with it 🐂 Castle Biosciences Bull Case

DCF And Targets Contrast With Ongoing Losses

• At a share price of US$19.24, the stock is presented as trading about 76.3% below a DCF fair value of roughly US$81.25, while the analyst consensus price target of US$47.25 sits well above both the current price and the trailing 12 month loss of US$12.8 million.
• Bears highlight that revenue is only forecast to grow at 8.5% a year compared with 11.4% for the wider US market and that the company remains unprofitable, which they see as a risk when the implied upside from both DCF and analyst targets already incorporates significant improvement.
  • The mixed valuation picture, with a P/S of 1.7x versus 1.2x for the broader US Healthcare industry and 2.2x for peers, underlines how sensitive any thesis is to whether future margins reach the levels needed to support those higher values.
  • For skeptics, the combination of ongoing quarterly losses, slower forecast revenue growth than the wider market and a P/S premium to the industry means the gap between the current US$19.24 price and the US$47.25 target or DCF fair value is only attractive if profitability arrives roughly as projected.

For a closer look at why some investors remain cautious despite the big gap to fair value estimates, it is worth reading the detailed bear case that walks through these concerns in context 🐻 Castle Biosciences Bear Case

Next Steps

To see how these results tie into long-term growth, risks, and valuation, check out the full range of community narratives for Castle Biosciences on Simply Wall St. Add the company to your watchlist or portfolio so you'll be alerted when the story evolves.

After weighing the bulls and bears, it helps to look past the headlines and test your own view while the story is still evolving. To see what is driving the optimism in the current thesis and which potential upsides stand out most, start by reviewing the 3 key rewards.

See What Else Is Out There

Castle Biosciences still carries recurring losses and a mixed margin story, so profitability and consistency are not yet lining up with the bullish expectations.

If you want stocks where the financial profile looks more compelling today, use the 51 high quality undervalued stocks to quickly spot companies that combine quality with attractive pricing.

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.