Castle Biosciences (CSTL) FCF Margin (2018 - 2026)
Castle Biosciences' (CSTL) quarterly FCF Margin came in at 6.33% in Q2 2026, down 708.0% year-over-year from 1.04% in Q2 2025, and up 115.31% quarter-over-quarter from 41.33% in Q1 2026.
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Analysis
Castle Biosciences (CSTL) FCF Margin (2018 - 2026) Analysis & Trends
Castle Biosciences has disclosed FCF Margin across 9 years of filings, most recently posting 6.33% for Q2 2026.
- In Q2 2026, FCF Margin fell 708.0% year-over-year to 6.33%; the TTM figure through Jun 2026 stood at 0.14% (down 1011.0% YoY), while the FY2025 annual figure was 8.23%, down 277.0% from the prior year.
- FCF Margin came in at 6.33% for Q2 2026 at Castle Biosciences, up from 41.33% in the prior quarter.
- In the past five years, FCF Margin ranged from a high of 22.7% in Q4 2025 to a low of 81.3% in Q1 2022.
- Average FCF Margin over 5 years is 9.53%, with a median of 4.04% recorded in 2025.
- The largest YoY upside for FCF Margin was 14094 bps in 2022 against a maximum downside of 12782 bps in 2022.
- Over 5 years, FCF Margin stood at 20.31% in 2022, then soared by 210 bps to 22.37% in 2023, then retreated by 13 bps to 19.46% in 2024, then increased by 17 bps to 22.7% in 2025, then sank by 72 bps to 6.33% in 2026.
- Per Business Quant data, the three most recent FCF Margin figures were 6.33% in Q2 2026, 41.33% in Q1 2026, and 22.7% in Q4 2025.
Peer Set
Peer Comparison
| # | Company | Market Cap | Enterprise Value | Gross Profit (Qtr) | FCF Margin (Qtr) |
|---|---|---|---|---|---|
| 1 | Natera | 53.05 Bn | 51.95 Bn | 486.15 Mn | -1.15% |
| 2 | Quest Diagnostics | 27.19 Bn | 26.87 Bn | 1.03 Bn | 15.08% |
| 3 | Labcorp Holdings | 25.93 Bn | 25.81 Bn | 1.11 Bn | 8.41% |
| 4 | Guardant Health | 23.97 Bn | 22.91 Bn | 219.03 Mn | -20.76% |
| 5 | Tempus AI | 13.64 Bn | 12.82 Bn | 274.25 Mn | -3.57% |
| 6 | Caris Life Sciences | 8.47 Bn | 7.68 Bn | 182.38 Mn | 2.43% |
| 7 | Sotera Health | 5.35 Bn | 4.99 Bn | 177.96 Mn | 13.08% |
| 8 | BillionToOne | 4.96 Bn | 4.41 Bn | 77.11 Mn | 4.65% |
| 9 | Adaptive Biotechnologies | 4.55 Bn | 4.21 Bn | 51.39 Mn | -10.60% |
| 10 | Castle Biosciences | 1.08 Bn | 811.36 Mn | 79.85 Mn | 6.33% |
Historic Data
Download Data
Historic Data
| Date | Value |
|---|---|
| Jun 30, 2026 | 6.33% |
| Mar 31, 2026 | -41.33% |
| Dec 31, 2025 | 22.70% |
| Sep 30, 2025 | 9.39% |
| Jun 30, 2025 | 13.41% |
| Mar 31, 2025 | -12.25% |
| Dec 31, 2024 | 19.46% |
| Sep 30, 2024 | 19.77% |
| Jun 30, 2024 | 21.57% |
| Mar 31, 2024 | -21.91% |
| Dec 31, 2023 | 22.37% |
| Sep 30, 2023 | 4.16% |
| Jun 30, 2023 | -15.60% |
| Mar 31, 2023 | -68.46% |
| Dec 31, 2022 | -20.31% |
| Sep 30, 2022 | -19.62% |
| Jun 30, 2022 | -29.87% |
| Mar 31, 2022 | -81.30% |
| Dec 31, 2021 | 107.51% |
| Sep 30, 2021 | -26.13% |
API Access
Castle Biosciences FCF Margin API
Pull this series into your own models, spreadsheets and apps with the Business Quant
Historical Metrics API. The request below matches the chart above — change the
frequency, period or values and it follows. Swap YOUR_API_KEY for your own key.
https://data.businessquant.com/historic?slug=fcf-margin&ticker=CSTL&period=max&api_key=YOUR_API_KEYimport requests
url = "https://data.businessquant.com/historic"
params = {"slug": "fcf-margin", "ticker": "CSTL", "period": "max", "api_key": "YOUR_API_KEY"}
data = requests.get(url, params=params).json()const res = await fetch("https://data.businessquant.com/historic?slug=fcf-margin&ticker=CSTL&period=max&api_key=YOUR_API_KEY");
const data = await res.json();