What Is a Steamfitter? Steamfitter Career Guide

A steamfitter is a pipe-trades specialist.

BLS describes pipefitters and steamfitters as the workers who install and maintain pipes that may carry chemicals, acids, and gases, and it draws the steamfitter boundary at pressure: steamfitters specialize in systems designed for the flow of liquids or gases at high pressure.

The trade's own organization puts it in more workshop terms.

The United Association (UA) — the union that represents the pipe trades — describes steamfitters as workers who fabricate, install, maintain, and repair high-pressure systems that move steam, hot water, and other industrial fluids, including chilled water and compressed air.

Its description of the work includes welding, rigging, and hydrostatic and pneumatic testing.

So the steamfitter definition, and the steamfitter meaning behind the name, comes down to one idea: pressure.

Steam only becomes a steamfitter's material when the system is built, joined, and tested to hold it — which is why fabrication, welding, and pressure testing sit inside the trade's own description of itself.

One quirk shapes everything written about this trade: the federal statistical system does not count steamfitters separately.

O*NET merged the old Plumbers code and the old Pipe Fitters and Steamfitters code into a single occupation, 47-2152.00 Plumbers, Pipefitters, and Steamfitters, and retired the old codes as no longer in use.

Every BLS pay or outlook figure for steamfitters is therefore a combined figure — this page labels it that way each time one appears.

Steamfitting is defined by what runs through the pipe.

The systems named in the BLS and UA descriptions of the trade are:

• Steam and hot-water systems — the high-pressure systems the UA names as the trade's core work, moving steam, hot water, and other industrial fluids.
• Chilled water and compressed air systems — both named by the UA among the fluids steamfitters' systems move.
• Process piping that may carry chemicals, acids, and gases — BLS describes pipefitter and steamfitter piping this way, which is what ties the trade to industrial work.
• Datacenter cooling and process piping — the UA lists datacenters among steamfitter work, supporting advanced cooling and process piping for mission-critical operations.

The joining and testing methods are part of the job, not an add-on.

In the UA's description, steamfitter work includes welding the joints, rigging heavy components into place, and proving each system with hydrostatic and pneumatic testing before it carries pressure.

Put the systems and the settings together and the steamfitter job description in one line: fabricate, install, maintain, and repair the piping that moves liquids or gases at high pressure — and test it until it is proven to hold.

BLS places pipefitter and steamfitter work mostly in manufacturing, commercial, and industrial settings — the factories, commercial buildings, and industrial facilities where high-pressure systems do real work, rather than the residential service route that defines household plumbing.

Most steamfitters work for contractors.

In 2025, 65% of plumber, pipefitter, and steamfitter jobs were with plumbing, heating, and air-conditioning contractors, and 8% of workers were self-employed, per BLS.

The OEWS industry counts show the same shape: Building Equipment Contractors employed 340,140 of these workers in May 2025 — by far the largest industry — followed by Utility System Construction at 14,960 and local government (excluding schools and hospitals) at 11,480.

The mechanical-contractor shop, not the factory floor, is where most of the trade is employed, even though the work it performs is industrial in character.

The schedule follows the systems.

BLS says most plumbers, pipefitters, and steamfitters work full time, including nights and weekends, and are often on call to handle emergencies — the high-pressure systems they keep running do not pause politely when something goes wrong.

The two titles sit inside the same BLS occupational family, and the agency describes them together: pipefitters and steamfitters both install and maintain pipes that may carry chemicals, acids, and gases, mostly in manufacturing, commercial, and industrial settings.

The difference is the specialty — steamfitters are the ones who specialize in systems designed for the flow of liquids or gases at high pressure.

Because O*NET merged the old Pipe Fitters and Steamfitters code with the Plumbers code into 47-2152.00, federal data cannot separate the two titles: no steamfitter-only wage, outlook, or employment count exists.

Comparisons between the two trades are about scope of work, not statistics — and any page that quotes a "steamfitter median" against a "pipefitter median" is presenting a split BLS does not publish.

Plumbers are the third title in the combined code, with a different center of gravity: BLS describes plumbers as installing and repairing water, gas, and other piping systems in homes, businesses, and factories, including fixtures such as bathtubs and toilets and appliances such as dishwashers and water heaters.

The dedicated pipefitter vs steamfitter and plumber vs steamfitter comparisons go deeper on those boundaries.

The standard route is an apprenticeship.

BLS says most plumbers, pipefitters, and steamfitters learn the trade through a 4- or 5-year apprenticeship, pairing 2,000 hours of paid on-the-job training a year with technical instruction; the programs are sponsored by unions, trade associations, and businesses.

Apprentices are paid while they learn — at less than a fully trained steamfitter's rate, with pay increasing as they learn to do more of the trade, per BLS.

BLS publishes no apprentice wage figure, so treat any specific apprentice number you see elsewhere with caution.

Licensing has no single national rule — where it exists, the level that issues it varies.

Minnesota licenses high-pressure steam and process piping workers statewide as master and journeyworker pipefitters through the Department of Labor and Industry (DLI), and Massachusetts licenses journeyman pipefitters at the state level.

Cities add a layer of their own: Omaha licenses steamfitters at the master and journeyman levels, each by exam, while New York City has no Department of Buildings licence called "steamfitter" — the city's skilled-trade licences cover adjacent work such as high pressure boiler operating engineer, oil burner equipment installer, and welder.

There is no steamfitter-only federal wage.

The figure BLS publishes covers all of SOC 47-2152 — plumbers, pipefitters, and steamfitters together: a median of $30.67 an hour, or $63,800 a year, in May 2025 (OEWS, released May 15, 2026).

Steamfitters are one slice of that combined number, and BLS does not publish the slice on its own.

The outlook is measured the same combined way: employment across the occupation is projected to grow 6.8% from 2025 to 2035, faster than the 3.5% all-occupation average, with 42,000 openings a year on average (BLS Employment Projections, 2025–35).

The United Association — the union whose description of the trade opens this guide — lists steamfitters among its trades, alongside pipefitters, plumbers, sprinkler fitters, welders, and HVACR service technicians.

In New York City, the steamfitters' union is the Enterprise Association of Steamfitters, UA Local 638.

BLS counts unions among the sponsors of the apprenticeship route described above, alongside trade associations and businesses.

For percentile and state-by-state tables, see the steamfitter salary page.

Career information, not legal advice. Licensing rules vary by state and city — confirm current requirements with the state licensing agency or city/county building department where you work.