Onterris, Inc. · NYSE:ONT

Onterris — Montrose Environmental Group — Q1 2025 Earnings Presentation

19 slides from Onterris's earnings presentation, May 8, 2025

1. Slide 1: Welcome to the Q1 2025 Earnings Call

   WELCOME TO THE Q1 2025 EARNINGS CALL May 8, 2025

2. Slide 2: © 2025 Montrose Environmental Group, Inc. • Proprietary and Confidential

   © 2025 Montrose Environmental Group, Inc. • Proprietary and Confidential 2

3. Slide 3: Key Updates

   » Key Updates

4. Slide 4: Q1 2025 Key Financial Results

   REVENUE $177.8M • 14.5% Increase over Q1 2024 • CONSOLIDATED ADJUSTED EBITDA1 $19.0M • 10.7% of Revenue • OPERATING CASH FLOW • $5.5M • $27.5M Increase over Q1 2024 • © 2025 Montrose Environmental Group, Inc. • Proprietary and Confidential 4

5. Slide 5: © 2025 Montrose Environmental Group, Inc. • Proprietary and Confidential

   ✓ • • ✓ ✓ • ✓ ✓ ✓ ✓ • • ✓ © 2025 Montrose Environmental Group, Inc. • Proprietary and Confidential 5

6. Slide 6: 2025 Guidance: Revenue and Consolidated Adjusted EBITDA

   Consolidated Adjusted EBITDA1 $103M to $96M $110M 2024 2025 • Revenue • $735M to $696M $785M • 2024 2025 • • • • • © 2025 Montrose Environmental Group, Inc. • Proprietary and Confidential 6

7. Slide 7: © 2025 Montrose Environmental Group, Inc. • Proprietary and Confidential

   1 2 • • • • 3 4 • • • • © 2025 Montrose Environmental Group, Inc. • Proprietary and Confidential 7

8. Slide 8: © 2025 Montrose Environmental Group, Inc. • Proprietary and Confidential

   — — — © 2025 Montrose Environmental Group, Inc. • Proprietary and Confidential 8

9. Slide 9: © 2025 Montrose Environmental Group, Inc. • Proprietary and Confidential

   • • • • • • • • • • © 2025 Montrose Environmental Group, Inc. • Proprietary and Confidential 9

10. Slide 10: Financial Overview

    Financial . Overview 4i. , i a TS

11. Slide 11: Q1 2025 Revenue by Geography

    Canada, 14% Other International, 4% • - $178M 1Q25 - US, 82% - • • - - • • © 2025 Montrose Environmental Group, Inc. • Proprietary and Confidential 11

12. Slide 12: Segment Results Q1 2025 vs Q1 2024

    (Q1 2025 compared to Q1 2024) • - - $58.6 $53.1 - Revenue • Q1 24 Q1 25 - - $16.3 $10.6 • 27.8% 19.9% Segment Adjusted EBITDA - Q1 24 Q1 25 © 2025 Montrose Environmental Group, Inc. • Proprietary and Confidential 12

13. Slide 13: Segment Results Q1 2025 vs Q1 2024

    (Q1 2025 compared to Q1 2024) • $59.0 $45.5 • Revenue Q1 24 Q1 25 $13.7 • $6.5 Segment Adjusted EBITDA Q1 24 Q1 25 - © 2025 Montrose Environmental Group, Inc. • Proprietary and Confidential 13

14. Slide 14: Segment Results Q1 2025 vs Q1 2024

    • - - $65.7 $51.3 - • - Revenue Q1 24 Q1 25 - $5.9 $5.0 • 9.8% 9.0% Segment Adjusted EBITDA - Q1 24 Q1 25 © 2025 Montrose Environmental Group, Inc. • Proprietary and Confidential 14

15. Slide 15: Appendix

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16. Slide 16: © 2025 Montrose Environmental Group, Inc. • Proprietary and Confidential

    © 2025 Montrose Environmental Group, Inc. • Proprietary and Confidential 16

17. Slide 17: © 2025 Montrose Environmental Group, Inc. • Proprietary and Confidential

    © 2025 Montrose Environmental Group, Inc. • Proprietary and Confidential 17

18. Slide 18: © 2025 Montrose Environmental Group, Inc. • Proprietary and Confidential

    © 2025 Montrose Environmental Group, Inc. • Proprietary and Confidential 18

19. Slide 19: © 2025 Montrose Environmental Group, Inc. • Proprietary and Confidential

    © 2025 Montrose Environmental Group, Inc. • Proprietary and Confidential 19

Montrose Environmental Group — Q1 2025 Earnings Presentation on 6ix