Analysis
NAICS 56121 is the 2022 NAICS industry for facilities support services, part of 5612 (Facilities Support Services).
It has only one more detailed code, 561210, which covers exactly the same activities; the definition, index entries and statistics are on that page.
Between 2018 and 2023 the number of establishments grew 44% and employment rose 4%. The 2018 count used NAICS 2017, so part of a large move can come from codes being redefined rather than from businesses opening or closing.
County Business Patterns counts 9,019 US establishments in this code in 2023, employing 283,836 people at an average annual payroll of $56,262 per employee (27th percentile of national industries). 51% of the establishments have fewer than five employees, which is close to the national mix.
Official definition
See industry description for 561210.
Source: US Census Bureau, NAICS 2022 Manual.