EXHIBIT 99.1 Summit Midstream Partners, LP 910 Louisiana Street, Suite 4200 Houston, TX 77002 Summit Midstream Partners, LP Reports First Quarter 2024 Financial and Operating Results Houston, Texas (May 2, 2024) – Summit Midstream Partners, LP (NYSE: SMLP) (“Summit”, “SMLP” or the “Partnership”) announced today its financial and operating results for the three months ended March 31, 2024. Highlights • Reduced net leverage ratio to approximately 3.9x, a dramatic reduction from 5.4x in the fourth quarter of 2 ...