The average Post Isd custodial salary was $20,766, which is 21 percent lower than the average salary for this job in Texas, and 36 percent lower then the average salary for this job nationwide. Custodial salary in Post Isd is usually between $18,322 and $24,245 (25th and 75th). The highest custodial salary in Post Isd was $25,690. There are 11 employees in Post Isd whose job title is custodial.