The study compares the indoor environmental quality (IEQ) and occupant satisfaction in WELL-certified and LEED-certified buildings. Using a statistical matching technique, the researchers matched 1634 occupant surveys from WELL-certified buildings to 1634 surveys from LEED-certified buildings, controlling for six key parameters. The results show that WELL-certified buildings had a 39% higher probability of occupant satisfaction compared to LEED-certified buildings. Overall, both WELL-certified (94%) and LEED-certified (73%) buildings had high satisfaction levels, but WELL-certified buildings consistently outperformed LEED-certified buildings across all IEQ parameters except for space availability. The study suggests that the human-centered design criteria of the WELL standard may contribute to higher occupant satisfaction, particularly in areas such as sound privacy and acoustic design. However, the exact reasons for the higher satisfaction in WELL-certified buildings remain unclear, and further research is needed to identify specific design enhancements that improve occupant satisfaction.The study compares the indoor environmental quality (IEQ) and occupant satisfaction in WELL-certified and LEED-certified buildings. Using a statistical matching technique, the researchers matched 1634 occupant surveys from WELL-certified buildings to 1634 surveys from LEED-certified buildings, controlling for six key parameters. The results show that WELL-certified buildings had a 39% higher probability of occupant satisfaction compared to LEED-certified buildings. Overall, both WELL-certified (94%) and LEED-certified (73%) buildings had high satisfaction levels, but WELL-certified buildings consistently outperformed LEED-certified buildings across all IEQ parameters except for space availability. The study suggests that the human-centered design criteria of the WELL standard may contribute to higher occupant satisfaction, particularly in areas such as sound privacy and acoustic design. However, the exact reasons for the higher satisfaction in WELL-certified buildings remain unclear, and further research is needed to identify specific design enhancements that improve occupant satisfaction.