Welding Certifications Explained: AWS, ASME & State Requirements

Welding certifications are not optional if you want the better-paying jobs. Structural welding on bridges and buildings, pipe welding in refineries, pressure vessel work in power plants — every one of these roles requires documented, tested proof that you can lay a code-quality weld. Employers and project owners demand it, and in many states, certain welding work requires a license on top of your certifications.

The median annual wage for welders is $51,000 (BLS, May 2024). But certified welders working in oil and gas, nuclear, or aerospace routinely earn $70,000–$100,000+. The certifications covered in this guide are the primary lever separating those two income levels.

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What Are Welding Certifications (And What They Aren’t)

A welding certification is not a license. It’s a performance test — you weld a test coupon to a specific code standard, a qualified inspector examines it (visually and often with X-ray or bend testing), and if it passes, you receive documentation that you can produce a code-quality weld in that process, position, and material.

That documentation is called a Welder Qualification Record (WQR) or Welder Performance Qualification (WPQ), depending on the standard. It proves to an employer or project inspector that you met a specific code on a specific date. Most certifications expire if you stop working in that process for 6 months, which is an important detail explained further below.

A welding license, by contrast, is issued by a state government. Not all states require welders to be licensed — but where licensing exists (primarily for pressure piping and certain structural applications), you typically need to pass a state-administered test that mirrors AWS or ASME standards. More on that in the state-by-state section below.

The three main bodies that matter in US welding are:

• AWS (American Welding Society) — governs structural steel, sheet metal, aluminum, and inspection certifications. The widest-used standards across construction and manufacturing.
• ASME (American Society of Mechanical Engineers) — governs pressure vessel and pressure piping work. Required in power plants, refineries, and any boiler work.
• API (American Petroleum Institute) — governs pipeline and refinery welding. Required if you want to work on oil and gas infrastructure.

Understanding which standard applies to the job you want is the first thing to figure out. Getting certified to the wrong code doesn’t help you — and study time and test fees aren’t cheap.

AWS Certifications

The American Welding Society (aws.org) is the dominant standards and certification body in the US. AWS certifications split into two categories: welder performance qualifications (what you do with a torch) and professional credentials (inspector, educator, engineer roles).

AWS Structural Welding Codes — D1 Series

These are the performance codes most welders encounter first. When an employer says “must be certified to D1.1,” this is what they mean.

Each D1.1 test is specific to a welding process (SMAW, GMAW, FCAW, GTAW), a position (flat/horizontal/vertical/overhead), and a joint configuration (groove or fillet). Passing a groove weld test in the 3G (vertical) position qualifies you for 3G and 2G positions — so testing in a harder position gives you broader coverage. Always test in the most challenging position you can pass — it maximizes the jobs your certification covers.

AWS Professional Credentials

These are credential programs with experience and examination requirements — not one-day performance tests.

AWS Certified Welding Inspector (CWI)

The CWI is the most valuable credential in the welding industry for anyone who wants to move off the torch and into inspection, quality control, or supervisory roles. CWIs earn $65,000–$100,000+ depending on industry.

Requirements to sit for the CWI exam:

• High school diploma or GED, plus 5 years of welding-related work experience, OR
• Associate degree in welding or related field, plus 4 years of experience, OR
• Bachelor’s degree in engineering or related field, plus 1 year of experience
• Vision test (must pass near and far vision, and color perception requirements)

The CWI exam has three parts: a Fundamentals exam (open-book, based on AWS B5.1 Standard), a Practical exam (visual examination of test specimens), and a Code Book exam (closed-book application of a specific code — D1.1 is most common, but you choose your code). All three must be passed within the same testing window. The pass rate for first-time test takers is approximately 50%.

Exam fee: approximately $1,000–$1,400 for AWS members ($1,400–$1,800 for non-members). The CWI is valid for 3 years and requires renewal through continuing education or re-examination.

Other AWS Professional Credentials

• Certified Welding Educator (CWE): For instructors at vocational schools and community colleges. Requires welding education experience plus examination. Typical salary bump: $5,000–$15,000/yr over non-credentialed instructors.
• Certified Welding Engineer (CWEng): Requires an engineering degree plus welding experience. For engineers designing welded structures.
• Certified Welding Sales Representative (CWSR): For sales professionals selling welding equipment and consumables. Less common, but useful in distributor roles.
• Certified Robotic Arc Welding (CRAW): For welders working on automated robotic welding cells. Growing in demand as manufacturing automation expands.
• Certified Radiographic Interpreter (CRI): Specialized credential for reading X-ray film of welds. Often paired with a CWI credential.

ASME Certifications

ASME (American Society of Mechanical Engineers) governs welding for pressure vessels, boilers, and pressure piping through its Boiler and Pressure Vessel Code (BPVC). This is the standard that matters in power generation, chemical processing, petroleum refining, and anywhere pressurized systems are built or repaired.

ASME welder qualifications are different from AWS in one critical way: ASME qualifications are issued by a specific employer (called an “authorized employer” or “manufacturer”), not directly to the individual welder. Your ASME qualification is tied to your employer’s quality program.

ASME Section IX — Welder Performance Qualifications

Section IX of the ASME BPVC defines how welders are tested and qualified for pressure-containing work. When a company holds an ASME stamp (authorization to fabricate or repair pressure equipment), they must qualify their welders under Section IX before those welders can work on stamped equipment.

What this means practically: you typically don’t “get an ASME certification” on your own the way you test for an AWS D1.1 cert. Instead, you’re qualified by an employer through their internal qualification program, which must follow ASME Section IX rules. Your qualification record stays with that employer.

Key ASME Codes for Welders

• ASME Section IX: Welder qualification for pressure vessels and piping (the foundational standard)
• ASME B31.1: Power piping — steam lines, boiler feedwater, turbine systems
• ASME B31.3: Process piping — chemical and petrochemical plants
• ASME B31.4: Pipeline transportation — liquid hydrocarbons
• ASME B31.8: Gas transmission and distribution systems

Working under ASME B31.1 or B31.3 in a nuclear or chemical plant can push annual earnings to $80,000–$120,000 for experienced pipe welders. These are among the highest-paying welding roles in the country.

ASME Stamps

ASME stamps are certifications held by companies, not individual welders — but knowing which stamps an employer holds tells you what kind of work they do and what qualifications you’ll need.

• S Stamp: Power boilers
• U Stamp: Pressure vessels
• R Stamp: Repairs and alterations (held by repair shops)
• PP Stamp: Pressure piping
• NB (National Board): For boiler and pressure vessel inspection — inspectors, not welders

API Certifications

The American Petroleum Institute (API) sets standards for the oil and gas industry. For welders, the two most important are API 1104 and, for inspectors, API 510/570/653.

API 1104 — Pipeline Welding

API 1104 governs welding of pipelines and related facilities — the transmission lines that move crude oil, natural gas, and refined products across the country. This is the standard you need if you want to weld on cross-country pipelines, gathering systems, or compressor station piping.

API 1104 qualification is similar in structure to ASME Section IX — it’s an employer-administered qualification following API rules. Pipeline contractors have their own written welding procedures, and you must pass a qualification test under those procedures before working on the line.

Key facts for API 1104 pipeline work:

• Typically done with SMAW (stick) or GMAW downhill processes — the speed demands of pipeline work drive process choice
• You’ll test on the specific pipe diameter and wall thickness you’ll be working on
• Travel is a significant part of pipeline work — many pipeline welders are away from home for weeks at a time
• Experienced pipeline welders earn $35–$65/hour depending on location and contractor

API Inspector Certifications

These are credential programs for inspection personnel in the petroleum industry. While not welding certifications per se, they’re common career progression for experienced welders and CWIs moving into inspection.

• API 510 (Pressure Vessel Inspector): For inspectors maintaining pressure vessels in refineries and chemical plants. Requires 3 years of relevant experience for engineers, 5 years for non-engineers.
• API 570 (Piping Inspector): For inspectors maintaining piping systems in process plants. Similar experience requirements to API 510.
• API 653 (Above Ground Storage Tank Inspector): For inspectors maintaining large storage tanks.

Combining a CWI with an API 510 or 570 credential is a common path for welding professionals targeting the petrochemical sector. Salaries for experienced API inspectors range from $90,000 to $140,000+.

State Licensing Requirements

This is where it gets complicated — because unlike electricians or plumbers, welders in most states don’t need a government-issued license to work. Certification to a code standard (AWS, ASME, API) is what most employers require, and that’s an employer-driven requirement, not a legal one.

However, specific states do require welding licenses for certain types of work. Here’s the breakdown:

Boiler work and pressure piping are the most consistently regulated areas. If you want to work on boilers in any state, check with that state’s department of labor or boiler safety office. The National Board of Boiler and Pressure Vessel Inspectors (nationalboard.org) maintains a directory of state boiler inspection programs that’s a useful starting point.

How to Get Certified: Step-by-Step Process

The path from “I want to get certified” to “I have a valid certification” looks different depending on which standard you’re pursuing. Here’s the general process for an AWS D1.1 certification — the most common first certification for working welders:

1. 1
   Identify the specific qualification you need Talk to your employer, review job postings in your target industry, or call a local AWS section. Know the standard (D1.1, ASME Sec. IX, etc.), the welding process (SMAW, GMAW, FCAW, GTAW), and the position (1G, 2G, 3G, 4G for plate; 1F–4F for fillet) before you book a test. Testing blind wastes money.
2. 2
   Find a testing facility AWS certifications can be administered by AWS-accredited testing facilities (ATFs) or by employers who maintain their own qualification programs under the code. Community colleges, vocational schools, and some AWS local sections maintain ATF status. Use the AWS ATF locator at aws.org to find facilities near you. Some testing facilities charge a facility fee ($75–$200) on top of AWS’s examination fees.
3. 3
   Practice to the specific WPS (Welding Procedure Specification) You’ll weld to a written Welding Procedure Specification — a document that specifies every variable: material, amperage range, travel speed, preheat requirements, filler metal. The testing facility provides the WPS. Get a copy in advance and practice to it exactly. Don’t practice your personal preferred technique — practice the procedure as written. This is where most failures happen.
4. 4
   Take the performance test You’ll weld test coupons (standardized test pieces) under the supervision of a qualified inspector. For D1.1 groove welds, your coupon will be visually examined and then either bend-tested (cut and bent to check for defects) or radiographically tested (X-rayed). Results are typically available same-day for visual and bend tests; X-ray results may take a few days.
5. 5
   Receive your Welder Qualification Record (WQR) If you pass, you receive a WQR documenting your qualification. This is your certification. Store physical and digital copies — employers will ask for it. For AWS certifications processed through aws.org, your certification is also logged in the AWS database and can be verified electronically, which many large contractors require.
6. 6
   Maintain your certification — don’t let it lapse Most welding certifications expire if you haven’t used the welding process for 6 consecutive months. Your employer should be maintaining your qualification continuity through periodic documentation (a 6-month continuity sign-off from your supervisor). If you’re between jobs, maintain continuity through your union hall, a school, or by retesting before the 6-month mark.

Which Certifications Are Worth the Investment

Not all certifications deliver equal return. Here’s a practical prioritization based on where the money actually is:

The highest-leverage move for most working welders is: get AWS D1.1 in 3G or 4G position first (broadest coverage, most jobs), then pursue ASME Section IX qualification through an employer doing pressure work, then stack the CWI if you have 5 years and want to move into inspection. That sequence covers the three biggest salary brackets in the trade.

Salary Impact of Welding Certifications

The BLS median for all welders is $51,000 per year (May 2024). That figure includes entry-level shop welders, fabricators, and highly specialized pipe and structural welders. Certifications are the primary variable that separates $40,000/year from $90,000/year within the same trade.

Salary ranges above reflect US market data and are influenced by location, union membership, overtime, and years of experience. Our welder salary guide has a full state-by-state breakdown of welder earnings.

Union membership is another significant variable. Welders represented by unions — primarily the International Brotherhood of Boilermakers (IBB) or the United Association (UA) for pipe welders — typically earn 20–40% more than their non-union counterparts, plus full benefits and pension contributions.

Frequently Asked Questions

Next Steps

The most important next step is figuring out which certification your target employer or industry actually requires — then testing for that one first, not collecting credentials across the board. Review job postings for the welding roles you want, note which codes they list, and contact a local AWS section (aws.org has a section locator) or your trade school to find testing options near you.

If you’re at the beginning of your welding career, our complete guide to becoming a welder covers training programs, apprenticeships, and how to build toward certified work from the ground up. For salary data on what welders actually earn at each experience level, see the welder salary guide.

See other trades’ licenses and certifications requirement guides:

• How to Get Your Electrician License
• Plumber License Requirements
• HVAC Certification & Licensing