Analysis
NAICS 33331 is the 2022 NAICS industry for commercial and service industry machinery manufacturing, part of 3333 (Commercial and Service Industry Machinery Manufacturing).
It has only one more detailed code, 333310, which covers exactly the same activities; the definition, index entries and statistics are on that page.
County Business Patterns counts 1,731 US establishments in this code in 2023, employing 80,504 people at an average annual payroll of $82,553 per employee (71st percentile of national industries). 32% of the establishments have fewer than five employees, which is close to the national mix.
Between 2018 and 2023 the number of establishments fell 8% and employment rose 13%. 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.
Its goods appear in 178 statistical lines of the US tariff schedule, mostly under headings 9006 (photographic (other than cinematographic) cameras…), 9002 (lenses, prisms, mirrors and other optical elements, of any…) and 9010 (apparatus and equipment for photographic (including…). That link is how import data is matched to domestic producers, for example in trade-remedy cases.
Official definition
See industry description for 333310.
Source: US Census Bureau, NAICS 2022 Manual.