NAICS Code Appending – Match NAICS Codes to Your Company Database


NAICS & SIC Appending
Add Industry Classification to Your Company Database

NAICS and SIC code appending is the process of matching companies in an existing database to their industry classifications and returning the file with those codes added.

SICCODE.com goes beyond basic code matching by reviewing the company and its website, determining what the business does, and assigning the appropriate government-level 6-digit NAICS and 4-digit SIC classifications. Extended 8-digit NAICS and 6-digit SIC classifications, confidence scoring, and supporting evidence can also be included when requested. Records that cannot be reliably matched or classified are flagged for review rather than treated as confirmed.

Industry classification data since 1998 Flat quote before purchase Your file stays private Original columns preserved
Government-Level Codes 6-digit NAICS + 4-digit SIC
Extended Classification 8-digit NAICS + 6-digit SIC
Confidence & Evidence Status, score, confidence and reasoning
Uncertain Records Flagged Unsupported classifications are not forced
Get a free sample and flat quote before the full project. Tell us your approximate record count, classification depth, and the fields you need. Typical response: 2–24 hours.

Try It First With a Free Sample

Send 10 to 25 rows from your file and we’ll return a sample so you can review the classifications, confidence information, and requested output before approving the full project.

No purchase required Review actual returned records Flat quote before the full project

Choose the Level of Classification You Need

Projects can include standard government-level industry codes, more detailed Extended classifications, and a review layer that documents how confidently each company was matched and classified.

Government-Level 6-digit NAICS + 4-digit SIC

Standard industry classifications used in government data, business databases, analytics, reporting, compliance, customer segmentation, and other classification workflows.

Extended 8-digit NAICS + 6-digit SIC

More detailed classifications that identify narrower business activities within the broader government-level industry classification.

Review Layer Confidence + Evidence

When included in the project scope, status, scoring, confidence, and supporting evidence show which classifications are strongly supported and which records require additional review.

Extended 8-digit NAICS and 6-digit SIC classifications provide additional specificity beyond government-level 6-digit NAICS and 4-digit SIC codes; they should not be interpreted as additional U.S. government classification levels.

What You Send vs. What You Get Back

Keep your existing file structure. We return your original records with the approved classification, verification, and enrichment fields added as new columns.

Your File
  • Company Nameexisting
  • Address / City / Stateif available
  • Website / Domainif available
  • Phone / Emailif available
  • Other Identifiersoptional
Returned With Classification & Enrichment
Company Matching Company Match · Website Status · Website Confidence · Confidence Note
Government-Level Classification 6-digit NAICS · NAICS Title · 4-digit SIC · SIC Title
Extended Classification 8-digit Extended NAICS · Extended NAICS Title · 6-digit Extended SIC · Extended SIC Title
Classification Quality Status · Score · Confidence · Evidence · Extended Code Confidence & Evidence
Business Understanding Business Summary · Products · Services
Optional Enrichment Address · Phone · Email · Website · Facebook · LinkedIn · Firmographics

Your original columns are not overwritten. Available output fields depend on project scope, source availability, and the information that can be reliably established for each record.

How SICCODE.com Classifies and Appends Industry Codes

The objective is not simply to attach a code to every row. The process is designed to identify the correct company, understand its primary business activity, apply the appropriate classification depth, and indicate when the available evidence does not support a confident result.

1

Match the Company

Use the available company information to determine whether the supplied record and identified website represent the intended business.

2

Understand the Business

Review available business information, including company activity, products, services, website content, and other relevant information.

3

Assign Government-Level Codes

Determine the appropriate 6-digit NAICS and/or 4-digit SIC classification based on the company's primary business activity.

4

Add Extended Classification

When included in the project, assign more specific Extended 8-digit NAICS and 6-digit SIC classifications.

5

Evaluate Confidence

When included in the project scope, we return classification status, scoring, confidence, notes, and supporting evidence.

6

Flag Uncertain Records

Records that cannot be reliably matched or classified are identified for review instead of being represented as confirmed classifications.

NAICS and SIC Code Appending Explained

What Is NAICS Code Appending?

NAICS code appending adds industry classifications to companies already contained in a spreadsheet, CRM, customer database, or other business file. SICCODE.com identifies the company, determines its primary activity, and appends the corresponding government-level 6-digit NAICS classification along with the industry title and other requested data.

What Is SIC Code Appending?

SIC code appending applies industry classifications from the Standard Industrial Classification system to companies in an existing business file. SICCODE.com appends government-level 4-digit SIC classifications and, when requested, more specific Extended 6-digit SIC classifications.

Classification Confidence & Supporting Evidence

Not every company record carries the same level of certainty. When included in the project scope, the returned file includes classification status, confidence, scoring, and supporting evidence so your team can distinguish strongly supported classifications from records that require additional review.

High Confidence

Company and Classification Supported

The company or website match is supported and the available evidence supports the assigned industry classification.

Review Needed

Some Evidence Is Incomplete

The company may be identified, but available information is not sufficient to treat every classification field as equally certain.

Unreliable / Do Not Use

Match or Classification Is Not Reliable

The available website or company information does not reliably correspond to the intended business or does not support a usable classification.

A record should not receive a confident classification simply because a code can technically be assigned. When the available evidence does not support a reliable company match or classification, the record is flagged rather than forced into a confirmed result.

Available Classification & Enrichment Fields

Choose only the fields your project needs. We include the requested fields in the sample and quote based on your file, use case, project scope, and source availability.

Industry Classification

  • NAICS
  • NAICS Title
  • SIC
  • SIC Title
  • Extended NAICS
  • Extended NAICS Title
  • Extended SIC
  • Extended SIC Title

Classification Review

  • Industry Code Status
  • Industry Code Score
  • Industry Code Confidence
  • Industry Code Evidence
  • Extended Code Score
  • Extended Code Confidence
  • Extended Code Evidence

Company & Website Verification

  • Domain
  • Website URL
  • Website Status
  • Company Match
  • Website Confidence
  • Confidence Note

Company Enrichment

  • Business Summary
  • Products
  • Services
  • Full Address
  • Phone
  • Email
  • Facebook
  • LinkedIn
  • Employee Size
  • Sales Volume
  • Year Established
  • Other Firmographics

Not every field is available for every company. Ask for a sample based on your own records to see the available output for your project.

How the Project Works

1

Tell Us About Your File

Describe your approximate record count, current fields, classification depth, and any enrichment you need.

2

Review a Sample & Quote

We return sample-coded records and provide a flat quote before the full project begins.

3

Approve the Project

Review the sample, requested fields, project scope, pricing, and turnaround before moving forward.

4

Receive Your Returned File

Your original file is returned with the approved classification, review, and enrichment fields added.

Your file stays yours. Files supplied for an appending project are used for that project and are not added to the SICCODE.com business database or resold as customer data. A small sample is enough to begin; you do not need to send your full database at the start.

Common Questions About NAICS & SIC Code Appending

How much does NAICS or SIC code appending cost?

Pricing depends on record count, requested classification depth, enrichment fields, and project complexity. You receive a flat quote before the full project begins.

What information do you need to classify a company?

We use the company name and available identifiers such as address, website, domain, phone, or other company details to establish the correct business. More complete identifying information helps distinguish similarly named companies and locations.

Do I need a website for every company?

No. Available identifying information varies by record. Website information is particularly useful for verifying a company and understanding its primary business activity, products, and services.

What happens if a company cannot be reliably classified?

We flag the record as unmatched, unclear, review-needed, or otherwise unsuitable rather than representing it as a confirmed classification.

Can you append both NAICS and SIC codes?

Yes. Projects can include NAICS, SIC, or both classification systems, depending on your use case and existing data.

What are Extended NAICS and SIC codes?

Extended classifications provide more detailed industry categories beyond government-level 6-digit NAICS and 4-digit SIC classifications. SICCODE.com provides Extended 8-digit NAICS and 6-digit SIC classifications when they are included in the project.

Can you include classification confidence and evidence?

Yes. When included in the project scope, returned records include industry-code status, score, confidence, evidence, Extended-code confidence, and supporting notes so your team can evaluate the strength of the classification.

Can you append additional company information?

Yes. Depending on project scope and source availability, returned records may also include company and website verification, business summaries, products, services, contact information, firmographics, and other requested business data.

Do I have to send my full file before receiving a quote?

No. You can describe the project and begin with a small sample. A full customer database is not required to start the conversation.

What file types can you work with?

CSV, Excel, and common CRM exports are typically suitable. If your data can be exported to a structured spreadsheet, it can usually be reviewed for an appending project.

Ready to Add NAICS or SIC Codes to Your Database?

Get a free sample and flat quote before committing to the full project. Tell us your approximate record count, the classification depth you need, and any company data you want added. Typical response: 2–24 hours.

GET FREE SAMPLE & QUOTE
SIC & NAICS classification expertise since 1998. SICCODE.com provides SIC and NAICS classification reference data, company classification services, business data, and industry-code research tools. For more information, see Classification Methodology, Verification Methodology, and Data Sources & Verification Process.

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What Our Clients Say

We needed a full list of companies within a specific SIC code in order to complete some target market analysis. SICCODE.com provided a comprehensive data set to review and analyze. The delivery was fast and comprehensive. The experience was simple, straightforward, and met our needs - we would recommend.

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