Exhibit 99.1 July 30, 2025 Investor Contact: Aaron Musgrave Vice President, Investor Relations 856-955-4029 aaron.musgrave@amwater.com Media Contact: Maureen Duffy Executive Vice President, Communications and External Affairs 856-955-4163 maureen.duffy@amwater.com AMERICAN WATER REPORTS SOLID SECOND QUARTER RESULTS NARROWS 2025 EPS GUIDANCE TO TOP HALF OF RANGE AFFIRMS LONG-TERM TARGETS CAMDEN, N.J., July 30, 2025 - American Water Works Company, Inc. (NYSE: AWK) today reported results for the quarter ended ...