Exhibit 99.1 News Release JLL Reports Financial Results for Fourth-Quarter and Full-Year 2023 Resilient business line revenue growth continued as the pace of the market-wide pullback in transaction activity eased CHICAGO, February 27, 2024 – Jones Lang LaSalle Incorporated (NYSE: JLL) today reported operating income of $290.4 million for the fourth quarter of 2023, up from$254.7 million last year, and $576.5 million for the full year, compared with$868.1 million in 2022. Diluted earnings per share were $3 ...