The Broker's Guide to Sic Codes Vs Class Codes Insurance

SIC codes vs class codes insurance is not a subtle distinction. SIC codes (Standard Industrial Classification) tell a carrier what industry a business belongs to. Insurance class codes (NCCI for workers' comp, ISO for GL and property) tell a carrier what premium to charge. Using them interchangeably, or entering the wrong code in the wrong field, creates submission errors, appetite mismatches, and incorrect rates. This checklist walks through both systems, where they appear in the submission process, and a sequential process to get both right on every commercial account.

Key Takeaways

• SIC codes are 4-digit government industry identifiers maintained by OSHA and the Census Bureau; they do not directly determine insurance rates and have not been substantially updated since 1987
• NCCI class codes are 4-digit workers' comp rating codes published by NCCI that determine the base rate per $100 of payroll; 700+ codes are active across NCCI states as of NCCI 2025 data
• ISO class codes are 5-digit GL and property rating codes published by ISO (Verisk) that determine base rates per unit of exposure (revenue, payroll, area, or units)
• A single SIC code frequently maps to multiple NCCI and ISO class codes; SIC 1711 (Plumbing, Heating, AC) maps to at least three distinct NCCI codes depending on the specific employee duties
• Carrier appetite systems screen submissions by SIC code before the underwriter ever sees the account; a wrong SIC code can trigger an automatic declination even if all other submission data is correct
• NAICS codes (6-digit) replaced SIC codes for federal government purposes in 1997, but the insurance industry continues to use SIC codes on ACORD applications and carrier clearance systems as of IIABA 2025 reporting

The Core Difference Between SIC Codes and Insurance Class Codes

SIC codes and insurance class codes answer different questions.

SIC codes answer: What industry does this business operate in?

Insurance class codes answer: What is the specific exposure this business presents, and what rate applies?

SIC code 5812 (Eating Places) covers every restaurant in the country, from a food truck to a fine dining establishment. It tells the carrier the general industry. It does not distinguish between a low-volume breakfast cafe and a high-volume bar with late-night operations. The insurance class code makes that distinction.

Where Each Code Appears in Insurance

Understanding where each code type appears helps agents avoid entering the wrong code in the wrong place.

Where SIC Codes Appear

ACORD 125 (Commercial Insurance Application): Field 30 on the ACORD 125 requests the SIC code. This is the primary location where agents enter SIC information. The SIC code on the ACORD 125 feeds into carrier appetite systems and is used for initial risk screening.

Carrier clearance systems: Many carriers use SIC codes to route submissions to the correct underwriting unit or to trigger automatic appetite decisions. An account in SIC 7371 (Computer Programming, Data Processing) routes differently than an account in SIC 8742 (Computer Maintenance and Repair).

Loss run requests: Some carriers and reinsurers organize loss data by SIC code for industry-level analysis.

OSHA reporting and EPA filings: Employers use SIC codes on OSHA 300 logs, EPA environmental reports, and federal tax forms.

Where Insurance Class Codes Appear

Workers' comp dec page: NCCI class codes appear on the policy declarations alongside the payroll allocation for each code and the applicable rate.

Workers' comp rating worksheet: The EMR calculation uses NCCI class codes to identify which losses belong to which classification bucket.

GL and property dec page: ISO class codes appear on the declarations with the exposure amount and rate for each classification.

Underwriting guidelines: Carriers publish appetite guidelines by ISO GL class code and NCCI class code. These are more granular than SIC-based appetite screens.

The SIC-to-Class-Code Mapping Problem

The most common misconception brokers encounter: one SIC code equals one insurance class code. It does not.

SIC codes describe industries. Insurance class codes describe specific operations and employee duties within those industries. The mapping is often one-to-many.

Example: SIC 1711 (Plumbing, Heating, Air Conditioning)

SIC 1711 covers every plumbing and HVAC contractor. NCCI breaks this single SIC code into multiple workers' comp codes based on the specific work employees perform:

• NCCI 5183: Plumbing (installing pipes, fixtures, and related equipment)
• NCCI 5537: Air Conditioning Equipment Installation (installing AC and refrigeration systems)
• NCCI 5536: Heating Equipment Installation (installing heating systems)

A mechanical contractor whose employees do all three types of work needs all three NCCI codes with separate payroll allocations. Using only SIC 1711 does not tell the underwriter which NCCI code governs.

Example: SIC 4213 (Trucking, Except Local)

SIC 4213 covers long-haul trucking broadly. NCCI assigns different codes based on cargo type:

• NCCI 8227: Trucking, long-haul (general freight)
• NCCI 7228: Trucking, hauling logs
• NCCI 7219: Trucking with drivers under permanent hire

Cargo type changes the risk profile and the rate. A broker who assigns SIC 4213 without researching the applicable NCCI code will produce an inaccurate workers' comp premium.

Example: SIC 5812 (Eating Places)

SIC 5812 covers all restaurants. ISO differentiates for GL purposes:

• ISO 97047: Full-service restaurants (sit-down dining)
• ISO 97050: Fast food restaurants (counter service, no table service)
• ISO 16916: Bars and cocktail lounges (higher rate reflecting liquor liability exposure)

A bar classified as a full-service restaurant under ISO 97047 is underrated for its actual exposure. The carrier discovers this at audit or renewal underwriting and adjusts.

Checklist: Getting SIC Codes and Class Codes Right on Every Submission

Follow this seven-step checklist for every commercial account.

Step 1: Collect the SIC Code

• Ask the client for their primary business activity, not their company name
• Look up the correct SIC code at the OSHA SIC Manual (osha.gov/sic-search) or the SEC EDGAR SIC code list
• Verify the SIC code matches the client's actual operations, not just the industry they describe themselves as being in
• If the client operates in multiple lines of business, identify the SIC code for the primary revenue-generating activity
• Enter the SIC code on the ACORD 125 in field 30
• Confirm: does this SIC code fall within your target carriers' appetite? If not, research which carriers write this SIC range before proceeding

Step 2: Research the Specific Operations

• Ask the client to describe what employees do on a typical workday
• Ask specifically about any secondary activities (subcontracting, delivery, installation, office work)
• Document the approximate percentage of payroll allocated to each distinct activity
• Identify any operations that started or changed in the past 12 months

Step 3: Determine the NCCI Workers' Comp Class Codes

• List every employee role by actual duties, not job title
• Look up the applicable NCCI class code for each role in the NCCI Scopes Manual
• Apply the governing classification rule: employees with mixed duties go under the highest-rated code that covers any of their regular duties
• Apply standard exception rules: separate clerical (8810), outside sales (8742), and engineering/architecture (8601) payroll if employees meet strict separation requirements
• Allocate payroll to each class code based on actual employee distribution
• Compare against prior policy declarations and audit reports for consistency

Step 4: Determine the ISO GL Class Codes

• Identify every distinct operation the client performs that generates revenue or exposure
• Look up each operation in ISO's Commercial Lines Manual
• Confirm the exposure base (revenue, payroll, area, or units) for each ISO classification
• If multiple operations exist, assign each to its own ISO code with the appropriate exposure allocation
• Verify the exposure figures against client financial records (revenue, payroll, square footage, unit count)
• Cross-reference with the SIC code: the SIC and ISO codes should describe the same business from complementary angles

Step 5: Determine ISO Property Class Codes

• Confirm construction type through inspection reports, building plans, or municipal records (do not rely on client self-description)
• Verify protection class (PPC) for the property's location through ISO's PPC lookup tool
• Identify the occupancy classification based on the highest-hazard use of the building
• If the building has multiple tenants, classify based on the highest-hazard tenant's operations
• Confirm the building's year built, square footage, and current replacement cost value

Step 6: Cross-Reference and Validate

• Verify SIC-to-class-code consistency: a business with SIC 1521 (General Contractors, Residential) should have NCCI codes in the 5000 construction range and ISO GL codes for contracting operations
• Flag any mismatch between the SIC code on the application and the class codes on the rating page
• Verify: does the NAICS vs. SIC field distinction matter for this carrier? Some newer carrier systems accept NAICS but label the field as "SIC." Confirm before entering a 6-digit NAICS code in a 4-digit SIC field
• Document the rationale for each code selection in your submission notes

Step 7: Submit with Documentation

• Record all code selections and rationale in the agency management system
• Attach the operations description document to the submission
• Note any ambiguous classifications and how you resolved them
• Flag any accounts where the SIC code may trigger carrier appetite screening even though the operations are acceptable

Common SIC-to-Class-Code Mapping Reference

This mapping is approximate. Many SIC codes map to multiple NCCI and ISO codes depending on the specific operations. Always verify against the Scopes Manual (NCCI) and Commercial Lines Manual (ISO).

Three Scenarios Where SIC Codes Create Submission Problems

Scenario 1: Appetite Screening Mismatch

A technology consulting firm entered SIC 7371 (Computer Programming, Data Processing) on their ACORD application. The carrier's appetite system flagged 7371 as restricted because the carrier does not write data centers or software development companies. The actual business is a management consulting firm that uses software as a reporting tool, with no software development or data center operations.

The correct SIC code was 7389 (Services, Management Consulting). The wrong SIC triggered an automatic declination. The submission required manual intervention, a revised application, and a three-day delay. BLS 2024 data on commercial insurance submissions shows that SIC-driven appetite declinations add an average of four days to submission turnaround.

Scenario 2: NAICS vs. SIC Confusion

A carrier's online application asked for "Industry Code." The agent entered the client's 6-digit NAICS code (236115, New Single-Family Housing Construction) in what was actually a 4-digit SIC field. The carrier's system rejected the entry and routed the submission to manual review, adding five business days to the process.

NAICS replaced SIC codes for federal government purposes in 1997. The insurance industry still predominantly uses SIC. When an application does not specify which system it uses, assume SIC and confirm before entering a 6-digit code.

Scenario 3: Outdated SIC Codes for New Business Models

SIC codes have not been substantially updated since 1987. Entire industries lack SIC codes: social media platforms, drone services, cannabis operations, and cloud computing do not have dedicated SIC codes. IIABA 2025 guidance recommends using the closest matching SIC code and adding a narrative description on the application explaining the actual business model.

An agent placing coverage for a drone inspection service used SIC 7389 (Services, Not Elsewhere Classified) with a narrative explanation. The carrier's underwriting guidelines had separate handling instructions for drone operations based on the narrative description rather than the SIC code alone.

For class code selection best practices, see class code selection best practices. For NCCI-specific code lookup methods, read NCCI classification code lookup.

FAQ

What is the difference between a SIC code and an insurance class code?

A SIC code (Standard Industrial Classification) is a 4-digit government code that identifies a business's industry for statistical, regulatory, and appetite-screening purposes. It does not directly determine insurance rates. An insurance class code (NCCI for workers' comp, ISO for GL and property) is a rating code that determines the specific premium rate for a commercial policy. Class codes are published by NCCI and ISO and are updated regularly to reflect current loss experience. A business has one SIC code describing its industry and may have several NCCI and ISO class codes describing its specific operations and exposures.

Do SIC codes directly determine insurance rates?

No. SIC codes do not set insurance rates. They are used by carriers for industry identification and appetite screening. The actual rate on a workers' comp or GL policy comes from the NCCI or ISO class code, which is more specific than the SIC code. Carriers may use SIC codes to route submissions, apply preliminary appetite decisions, or categorize accounts in their portfolio reporting, but the premium calculation itself relies on NCCI and ISO class codes.

How does a broker find the correct workers' comp class code from a SIC code?

A SIC code is a starting point, not an answer. Brokers use the NCCI Scopes Manual cross-reference feature to find NCCI codes associated with a given SIC code, then read the full scope description to confirm the match against the insured's actual employee duties. Since one SIC code often maps to multiple NCCI codes, the specific operations must be evaluated to determine which code applies. For example, SIC 1711 maps to NCCI 5183 (plumbing), 5537 (air conditioning), and 5536 (heating). A broker must know what the employees actually do to assign the correct NCCI code.

Can one SIC code map to multiple insurance class codes?

Yes, frequently. SIC codes describe industries at a high level. Insurance class codes describe specific operations within those industries. SIC 4213 (Trucking, Except Local) maps to multiple NCCI codes based on cargo type and driver arrangement. SIC 5812 (Eating Places) maps to different ISO GL codes for full-service restaurants, fast food operations, and bars. SIC 1711 maps to three different NCCI codes based on the type of mechanical work performed. Brokers must evaluate the actual operations and employee duties to determine which class codes apply within a given SIC category.

Where does the SIC code appear on ACORD applications?

The SIC code appears in field 30 on the ACORD 125 (Commercial Insurance Application). This is the standard commercial lines application used across most carriers and lines. The ACORD 125 is the primary document where the SIC code is formally entered and transmitted to the carrier. Some carriers also request SIC codes on supplemental applications and loss run request forms. The SIC code on the ACORD 125 flows into carrier appetite and clearance systems before the underwriter reviews the full submission.

What happens if the SIC code on the application does not match the actual operations?

Two problems occur. First, the SIC code feeds carrier appetite systems. If the SIC code triggers a restricted or declined appetite category even though the actual operations are acceptable, the submission may be automatically declined or delayed. Second, if the SIC code is inconsistent with the selected class codes, an attentive underwriter may flag the discrepancy as a submission quality issue, delaying the quote. IIABA 2025 data shows that SIC code inconsistencies contribute to 15% of submission delays in commercial lines. Always verify that the SIC code on the ACORD 125 accurately represents the client's primary operations before submitting.

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Written by Javier Sanz, Founder of BrokerageAudit. Last updated April 2026.