The objective of this study was to develop and test a user-friendly greenhouse gas (GHG) emissions accounting tool for water utilities. The tool was designed to assist utilities in calculating GHG emissions for the purposes of complying with future regulation and reporting requirements, providing information for city and state climate action plans, and fulfilling voluntary carbon emissions goals. For utilities lacking accurate energy use data, equations were developed to predict energy use for three phases of water production: raw water collection, water treatment, and finished water distribution. The tool was tested by seven Georgia, North Carolina, and South Carolina utilities, which had an average carbon intensity of 1,240 kg carbon dioxide equivalents (CO2-eq)/mil gal when scope 1 and 2 emissions were evaluated. However, the averages ranged from 550 to 2,190 kg CO2-eq/mil gal, depending on the electrical grid used.