Rexx متوفر مع VM/SP إلى، الإصدار 2 من TSO/E ،إلى OS/2 (1.3 on up), و PC DOS (7.0 or 2000) و Windows NT 4.0 (الموارد Resource Kit: Regina).
Rexx is supplied with VM/SP on up, TSO/E Version 2 on up, OS/2 (1.3 and later, where it is officially named "Procedures Language/2"), AmigaOS Version 2 on up, PC DOS (7.0 or 2000), and Windows NT 4.0 (Resource Kit: Regina).