Arizona's contractor licensing system is one of the most detailed in the country. The Arizona Registrar of Contractors (ROC) uses a classification system that defines exactly what type of construction work each license holder is authorized to perform. Understanding these classifications is essential whether you are applying for your first license or considering adding a new classification to your existing business.
This guide breaks down every series of Arizona contractor license classifications, explains what each one covers, and helps you determine which classification is right for your business goals.
Why Classifications Matter: Performing work outside your authorized classification is treated the same as contracting without a license — a Class 1 misdemeanor in Arizona. It can result in fines, license suspension or revocation, and civil liability. Choosing the right classification from the start saves you time, money, and legal headaches.
How Arizona Structures Contractor License Classifications
Arizona organizes contractor licenses into five main series, each identified by a letter prefix. Within each series, specific numerical codes define the scope of authorized work. The five series are:
- A-Series: General Engineering contractors
- B-Series: General Commercial and Residential contractors
- C-Series: Specialty contractors (the largest category)
- D-Series: Limited Specialty contractors (subset of C-series with volume limits)
- K-Series: Manufactured Housing contractors
Each classification requires its own application, trade-specific exam, and fees. However, the business management exam is the same across all classifications, so you only need to pass it once. You can hold multiple classifications under a single business entity.
If you are new to the licensing process, read our complete guide to getting a contractor license in Arizona for the step-by-step application process.
A-Series: General Engineering Contractors
What A-Series Licenses Cover
A-series licenses are for contractors who perform engineering-related construction work. This includes infrastructure projects like roads, bridges, dams, water and sewer systems, and large-scale excavation. A-series work is typically associated with public works projects and heavy civil construction rather than residential building.
The A-series includes both a general engineering classification and several specialty subcategories:
| Code | Classification | Scope |
|---|---|---|
| A | General Engineering | All engineering construction: roads, bridges, dams, pipelines, utilities, grading |
| A-5 | Excavating, Grading, and Oil Surfacing | Earthwork, grading, paving, and related surface work |
| A-7 | Piers, Docks, and Marine Construction | Waterfront structures and marine engineering |
| A-9 | Swimming Pools | Commercial and residential pool construction (structural) |
| A-11 | Horizontal Boring, Blasting, and Tunneling | Underground boring, tunnel construction, blasting operations |
| A-12 | Sewers, Drains, and Pipe Laying | Underground piping, sewer systems, drainage infrastructure |
| A-14 | Water and Power Pipelines | Transmission pipelines for water, natural gas, and similar utilities |
| A-17 | Lines, Poles, and Towers | Power lines, communication towers, utility poles |
| A-19 | Swimming Pool Service and Repair | Pool equipment repair, resurfacing, and maintenance |
Who Should Get an A-Series License?
If you are primarily interested in residential or commercial building construction, the A-series is likely not the right fit. A-series licenses are designed for heavy civil and infrastructure contractors. However, if your business involves pool construction (A-9), pool service (A-19), or earthwork and grading (A-5), these classifications could be exactly what you need. Once licensed, getting found by customers in your area comes down to local SEO and a strong Google Business Profile.
B-Series: General Commercial and Residential Contractors
What B-Series Licenses Cover
B-series licenses are the broadest building contractor licenses in Arizona. They authorize the holder to perform or supervise work across multiple trades and manage entire construction projects. If you want to build homes, manage renovation projects, or act as a general contractor on commercial sites, the B-series is where you want to be.
| Code | Classification | Scope |
|---|---|---|
| B | General Commercial Contractor | All commercial building construction, renovation, and remodeling |
| B-1 | General Commercial Contractor | Same as B — commercial construction and renovation of all types |
| B-2 | General Residential Contractor | New home construction, residential remodeling, room additions, and all residential work |
| B-3 | General Remodeling and Repair Contractor (Residential) | Residential remodeling, repair, and renovation (not new home construction) |
| B-4 | General Remodeling and Repair Contractor (Commercial) | Commercial remodeling, tenant improvements, and repair work |
| B-5 | General Residential Contractor (no single project over $250K) | Residential building with a per-project dollar cap |
| B-6 | General Commercial Contractor (no single project over $250K) | Commercial building with a per-project dollar cap |
B-1 vs. B-2: Which Do You Need?
This is the most common question new contractors ask. The answer depends on what type of structures you plan to build or renovate:
- B-1 (General Commercial): Allows you to build and renovate commercial structures — offices, retail spaces, restaurants, warehouses, and multi-family buildings over a certain size. This is essential if you plan to bid on commercial projects or government contracts.
- B-2 (General Residential): Allows you to build new homes, perform whole-house renovations, manage additions, and oversee all residential construction trades. This is the most popular license in Arizona and the standard for residential builders and remodelers.
Many growing contractors eventually obtain both the B-1 and B-2 classifications, giving them maximum flexibility. Some start with a B-2 and add the B-1 after building their residential portfolio. Either way, the moment your license is active, your priority shifts to filling your pipeline — our guide on how to get more leads as a contractor covers exactly how to do that.
B-3 and B-4: The Remodeling-Only Option
If you do not plan to build new structures from the ground up, the B-3 (residential remodeling) or B-4 (commercial remodeling) classifications provide a narrower scope that still covers a wide range of work. These are popular with kitchen and bath remodelers, home renovation companies, and commercial tenant improvement contractors.
Pro Tip: The B-2 license includes the authority to do all B-3 work (residential remodeling). If you might ever want to build new homes, apply for the B-2 instead of the B-3 — the exam is only slightly more comprehensive and the classification is significantly more versatile.
C-Series: Specialty Contractors
What C-Series Licenses Cover
The C-series is the largest classification group, covering over 80 specialty trade licenses. These authorize contractors to perform specific types of construction work without the broad scope of a general contractor license. If you are a tradesperson focused on a single discipline — HVAC, electrical, plumbing, roofing, painting, landscaping, or dozens of others — this is your series.
Here are the most commonly held C-series classifications in Arizona:
| Code | Classification | Common Work |
|---|---|---|
| C-4 | Boilers, Steamfitting, and Process Piping | Boiler installation, steam systems, industrial piping |
| C-7 | Carpentry | Framing, finish carpentry, cabinetry installation |
| C-8 | Floor Covering | Hardwood, tile, carpet, vinyl, and laminate flooring |
| C-9 | Concrete | Foundations, slabs, driveways, flatwork, decorative concrete |
| C-11 | Electrical | Residential and commercial electrical systems, panels, wiring |
| C-14 | Drywall | Drywall hanging, taping, finishing, and repair |
| C-21 | Landscaping and Irrigation | Hardscape, softscape, irrigation systems, outdoor lighting |
| C-27 | Lightweight Partitions | Metal framing, acoustic ceilings, movable partitions |
| C-31 | Masonry | Block, brick, stone, and CMU construction |
| C-33 | Painting and Wall Covering | Interior and exterior painting, wallpaper, textured finishes |
| C-36 | Plastering | Stucco, plaster, and EIFS systems |
| C-37 | Plumbing | Residential and commercial plumbing systems |
| C-39 | Air Conditioning and Refrigeration | HVAC installation, repair, and maintenance |
| C-40 | Insulation | Thermal and acoustic insulation for buildings and piping |
| C-42 | Roofing | Roof installation, repair, and waterproofing |
| C-45 | Sheet Metal | HVAC ductwork, metal fabrication, flashing |
| C-49 | Refrigeration | Commercial refrigeration systems and walk-in coolers |
| C-53 | Water Well Drilling | Residential and commercial well drilling |
| C-57 | Wrecking | Building demolition and deconstruction |
| C-61 | Glazing | Window and glass installation, storefronts, mirrors |
| C-74 | Dual Licensed (Electrical and Plumbing) | Combined electrical and plumbing work |
| C-77 | Plumbing (including solar) | Plumbing with solar water heating capability |
| C-78 | Low Voltage | Alarm systems, data cabling, home automation, security cameras |
| C-80 | Painting (Residential) | Residential interior and exterior painting |
This is not an exhaustive list — Arizona has over 80 C-series classifications. Visit the ROC website for the complete catalog, or contact us if you need help identifying the right classification for your trade.
C-Series Advantages and Limitations
The main advantage of a C-series license is focus. You can start your business faster because the trade exam is specific to your discipline, and your bond and insurance requirements may be lower than for a general contractor. C-series contractors in high-demand metro areas like Phoenix and Mesa often reach full capacity within their first year when they pair their license with a solid lead generation system and a CRM built for contractors.
The main limitation is scope. A C-39 HVAC contractor cannot perform electrical work, even if it is incidental to an HVAC installation. You either need to subcontract that work to a licensed C-11 electrical contractor or obtain the additional classification yourself.
D-Series: Limited Specialty Contractors
What D-Series Licenses Cover
D-series classifications mirror certain C-series specialties but with a dollar limit per project. They are designed for smaller contractors or those just getting started who do not need (or qualify for) the full C-series scope. The trade exam for a D-series license is typically the same as the corresponding C-series, but the bond requirements are lower.
Common D-series classifications include:
| Code | Classification | Scope / Limit |
|---|---|---|
| D-3 | Limited Electrical | Electrical work with per-project dollar caps |
| D-9 | Limited Plumbing | Plumbing work with per-project dollar caps |
| D-11 | Limited Air Conditioning | HVAC work with per-project dollar caps |
| D-34 | Limited Roofing | Roofing work with per-project dollar caps |
Should You Start with a D-Series?
The D-series can be a good entry point if you are building your business incrementally and want lower startup costs (reduced bond amounts). However, many contractors find the project dollar limits restrictive as their business grows. If you can meet the full C-series requirements, it is usually better to apply for the C-series classification directly.
Growth Strategy: Some contractors start with a D-series license to begin operating quickly and legally, then upgrade to the corresponding C-series classification within 6-12 months as their revenue and experience grow. The ROC allows this upgrade without restarting the entire licensing process.
K-Series: Manufactured Housing Contractors
What K-Series Licenses Cover
K-series classifications are specific to manufactured (mobile) and modular housing. Arizona has a large manufactured housing market, particularly in retirement communities and rural areas. K-series licenses cover everything from installation and setup to repairs and specialty work on manufactured homes.
| Code | Classification | Scope |
|---|---|---|
| K-5 | Manufactured Home Setup | Installation, leveling, skirting, and setup of manufactured homes |
| K-6 | Manufactured Home Repair | General repairs and maintenance on manufactured housing |
| K-7 | Manufactured Home Electrical | Electrical work specific to manufactured homes |
| K-8 | Manufactured Home Plumbing | Plumbing systems in manufactured homes |
| K-9 | Manufactured Home HVAC | HVAC systems specific to manufactured housing |
| K-21 | Manufactured Home General Contractor | Comprehensive work on manufactured housing structures |
K-Series vs. Standard Licenses
A standard C-series or B-series license does not automatically authorize work on manufactured homes, and K-series licenses do not authorize work on site-built structures. If your market includes both manufactured and site-built housing, you will need licenses from both series.
How to Choose the Right License Classification
Choosing your classification is one of the most important decisions you will make when starting your contracting business. Here is a framework to guide your decision:
1. Define Your Core Service
What work will generate 80% of your revenue? If you are an HVAC technician, C-39 is the obvious choice. If you are a general handyman doing whole-home renovations, a B-2 or B-3 provides the broadest scope. Be honest about what you are qualified to do and what the market demands in your area.
2. Consider Your Growth Plans
Where do you want your business to be in 3-5 years? If you plan to move from specialty work into general contracting, it may be worth getting the broader license now rather than adding it later. Each additional classification requires a separate exam and application fee.
3. Research Your Local Market
Different Arizona markets favor different classifications. In Phoenix and Tucson, C-39 (HVAC), C-42 (Roofing), and B-2 (General Residential) are extremely high-demand. In rural areas, broader classifications like B-2 give you more flexibility to serve a smaller customer base. The contractors winning in competitive metros are the ones leveraging AI-powered tools to respond to leads faster and automate the repetitive work that slows everyone else down.
4. Talk to the ROC
If you are unsure which classification fits your intended work, call the ROC directly. Their licensing staff can review your planned scope of work and recommend the appropriate classification. This prevents expensive mistakes.
5. Plan for Multiple Classifications
Many successful contractors hold 2-3 classifications. For example, a residential builder might hold a B-2 (General Residential), C-42 (Roofing), and C-9 (Concrete). This allows them to self-perform key trades while also acting as the general contractor. Each additional classification strengthens your competitive position and reduces your reliance on subcontractors.
Need Help Deciding? Arizona Contractor Academy works with contractors at every stage — from choosing their first classification to scaling a multi-trade operation. Our growth plans include market analysis that shows you which classifications are most profitable in your service area. Get your free growth plan and we will help you build a licensing strategy that matches your goals.
Frequently Asked Questions
How many contractor license classifications does Arizona have?
Arizona has over 140 individual contractor license classifications organized into five main series: A-series (general engineering), B-series (general commercial and residential contracting), C-series (specialty trades), D-series (limited specialty), and K-series (manufactured housing). Each classification authorizes specific types of construction work.
What is the difference between a B-1 and B-2 license in Arizona?
A B-1 (General Commercial Contractor) license allows you to build or renovate commercial structures and perform work across multiple trades. A B-2 (General Residential Contractor) license is the residential equivalent, allowing you to build or renovate homes and manage multiple subcontractors. The B-2 is the most common license for residential builders and remodelers.
Can I hold multiple contractor license classifications in Arizona?
Yes, you can hold multiple license classifications under a single business entity. Each additional classification requires its own application, trade exam, and fees. Many contractors start with a specialty classification and later add a general contractor classification as their business grows.
What is the most common contractor license in Arizona?
The B-2 (General Residential Contractor) is the most commonly held contractor license in Arizona, followed by C-series specialty licenses like C-39 (Air Conditioning and Refrigeration), C-77 (Plumbing), C-11 (Electrical), and C-42 (Roofing). The B-2 is popular because it allows the broadest scope of residential work.
What happens if I perform work outside my license classification?
Performing work outside your authorized classification is a violation of Arizona law. The ROC can impose fines, suspend or revoke your license, and require you to pay restitution. It is also considered contracting without a license for the unauthorized work, which is a Class 1 misdemeanor.