Short answer
To convert NAICS to SIC, or SIC to NAICS, enter either code in the box to see every match from the Census Bureau's concordances. Many matches are partial: 453 of the 1,004 SIC codes map to more than one NAICS 2022 code. SIC 5812, Eating Places, for example, splits into full-service restaurants (722511), limited-service restaurants (722513) and five other codes. Pick the match that describes your main activity.
- Only 238 SIC and NAICS 2022 codes pair up exactly one to one; most other matches are partial.
- The Census Bureau's official SIC concordance runs to 2002 NAICS; matches to 2022 are chained through each later revision.
- Chained matches can list dozens of codes that took only a sliver of the old one, so read the pieces.
- Head offices (NAICS 551114) have no SIC equivalent, because SIC coded them with the business they served.
- Use NAICS for federal forms and SIC only where a form or the SEC asks for it.
On this page
NAICS to SIC converter
Enter a NAICS or SIC code, or a few words, to see the matching codes in the other system. One code often maps to several, so check the titles.
Results appear as you type.
Source: US Census Bureau NAICS 2022 files and concordances, and County Business Patterns 2023 (establishments with paid employees). SIC matches come from the 1987 SIC to 2002 NAICS concordance, carried forward through each NAICS revision, so a match can cover only part of a code.
This page is for anyone holding one kind of code and needing the other: a NAICS code from SAM.gov when a bank form asks for SIC, a SIC code from an old customer record or an SEC filing when a federal form wants NAICS, or a prospect list built on SIC that you want to size with current Census data. Enter a code or a few words in the box above.
How the conversion works
When NAICS replaced SIC, the Census Bureau published a concordance from the 1987 SIC to 2002 NAICS. It breaks each SIC code into pieces by activity and assigns every piece a NAICS code. SIC 1711, Plumbing, Heating, and Air-Conditioning, has three pieces: environmental controls installation (now 238210, with electricians), general plumbing and HVAC work (238220) and septic tank construction (238910). The Census Bureau says it has no plans to build any other SIC concordance.
NAICS has been revised four times since 2002, so the converter chains the Census concordances forward: 2002 to 2007, 2007 to 2012, 2012 to 2017 and 2017 to 2022. Each step can split or merge codes again. A match therefore means "some or all of this code's activity," not "the same thing."
How often the codes match one to one
Counted from the chained Census concordances (our calculation):
| Number of matching codes | SIC codes (to NAICS 2022) | NAICS 2022 codes (to SIC) |
|---|---|---|
| None | 0 | 3 |
| Exactly one | 551 | 547 |
| Two | 187 | 220 |
| Three | 136 | 88 |
| Four or five | 75 | 70 |
| Six or more | 55 | 84 |
| Total | 1,004 | 1,012 |
Only 238 pairs match exactly in both directions, where a SIC code maps to a single NAICS code and that NAICS code takes nothing from any other SIC code. Examples include 8711 Engineering Services to 541330, 7371 Computer Programming Services to 541511, and 7373 Computer Integrated Systems Design to 541512.
Common SIC to NAICS conversions
| SIC | SIC title | NAICS 2022 matches |
|---|---|---|
| 5812 | Eating Places | 722511 full-service restaurants, 722513 limited-service restaurants, 722514 cafeterias and buffets, 722515 snack and nonalcoholic beverage bars, 722310 food service contractors, 722320 caterers, 711110 dinner theaters |
| 8742 | Management Consulting Services | 541611, 541612, 541613, 541614, and part of 561312 executive search |
| 7372 | Prepackaged Software | 513210 software publishers; 334610 for mass reproduction of software |
| 1521 | General Contractors, Single-Family Houses | 236115 new single-family construction, 236118 residential remodelers |
| 4213 | Trucking, Except Local | 484121 truckload, 484122 less than truckload, 484230 specialized freight, 484210 household moving |
| 8721 | Accounting, Auditing, and Bookkeeping Services | 541211 CPA offices, 541214 payroll services, 541219 other accounting services |
| 8011 | Offices and Clinics of Doctors of Medicine | 621111, 621112 mental health specialists, 621491 HMO medical centers, 621493 ambulatory surgical and emergency centers |
| 6531 | Real Estate Agents and Managers | 531210 agents and brokers, 531311 and 531312 property managers, 531320 appraisers, 531390 and three others |
Common NAICS to SIC conversions
Going the other way, one NAICS code can collect pieces of several SIC codes. Pick the SIC code whose title matches your activity, not the first one listed.
| NAICS 2022 | Title | SIC matches | Usually use |
|---|---|---|---|
| 541611 | Administrative Management and General Management Consulting Services | 8742 | 8742 |
| 722511 | Full-Service Restaurants | 5812 | 5812 |
| 238220 | Plumbing, Heating, and Air-Conditioning Contractors | 1711, 1791, 1796, 7699 | 1711 |
| 541512 | Computer Systems Design Services | 7373, 7379 | 7373 |
| 621111 | Offices of Physicians (except Mental Health Specialists) | 8011, 8031 | 8011, or 8031 for osteopaths |
The other SIC codes behind 238220 are slivers: cooling tower installation from 1791 Structural Steel Erection, industrial ventilation installation from 1796, and boiler cleaning from 7699 Repair Shops, NEC.
How to choose when a code maps to several
- Read the pieces, not just the titles. The concordance describes what each piece covers, such as "Grocery Stores (convenience stores without gas)." Find the piece that describes your business.
- Take the match for your main activity. As with any industry code, use the activity that earns the most revenue.
- Check the definition on the other side. Open the Census definition for the NAICS code, or the OSHA manual entry for the SIC code, and confirm the cross-references don't send your activity elsewhere.
- Ignore codes that took a sliver. If your business wasn't in the small piece that moved, the code it moved to isn't yours.
- Record both codes. Keep the pair on file so every form you fill in says the same thing.
Why some matches look strange
Chaining can produce long lists. SIC 5411, Grocery Stores, chains to 42 NAICS 2022 codes, from tire dealers to florists. Almost all grocery activity went to three: 445110 supermarkets and other grocery retailers, 445131 convenience retailers and 457110 gasoline stations with convenience stores. The long tail comes from one small piece, frozen food and freezer plan providers, which passed through nonstore retail codes that the 2022 revision spread across every type of retailer.
SIC 7389, Business Services, NEC, also maps to 42 codes, but for a different reason: it really was a catch-all, covering everything from notaries to trade shows. See the SIC code 7389 page for how to pick among them.
A few NAICS codes have no SIC match at all. The main one is 551114, Corporate, Subsidiary, and Regional Managing Offices. SIC classified a head office in the industry of the establishments it served, while NAICS classifies it by its own activity, so a corporate office that was "manufacturing" under SIC is sector 55 under NAICS.
Which code to use where
| Situation | Code to use |
|---|---|
| SAM.gov registration and federal bids | NAICS. Each solicitation names one NAICS code and its SBA size standard. |
| SBA size standards and certifications | NAICS |
| IRS business activity code | The IRS list, which is based on NAICS but groups some codes |
| SEC filings and EDGAR research | SIC, from the SEC's own code list |
| Census and BLS statistics | NAICS (County Business Patterns has used NAICS since 1998) |
| Bank, insurer or supplier form | Whichever it asks for; give both if the field allows |
Converting a prospect list
Illustrative example. The seller is fictional; the counts are County Business Patterns 2023.
A building-controls company's old ideal customer profile says "SIC 1711, 10 to 99 employees." The converter returns 238210, 238220 and 238910. Only one of them is mostly former 1711 work: 238220, Plumbing, Heating, and Air-Conditioning Contractors, with 111,207 establishments. Its establishments with 10 to 99 employees number 13,148 + 8,384 + 2,561 = 24,093. That's the market to size and prospect.
Adding the other two codes in full would have pulled in all 83,342 electrical contractor establishments (238210) and 41,777 site preparation contractors (238910), which took only small pieces of 1711. The list would have more than doubled with the wrong businesses. At volume, checking that each company really does the work is the slow part; Bebop researches each account in the list and explains why it fits.
Common mistakes
- Summing every match. Partial matches overcount, as the example shows.
- Converting to an old NAICS edition. Some crosswalks online stop at 2002 or 2017 codes, and some of those codes no longer exist.
- Treating the SEC's SIC as the company's NAICS. The SEC's code is for routing filings and is often broad. Classify from what the company does.
- Using SIC on federal forms. SAM.gov and the SBA work only in NAICS.
Next step: read the full definition and size standard for your NAICS match with the NAICS code lookup.
Sources
- NAICS concordances: 1987 SIC to 2002 NAICS, and 2002 to 2007, 2007 to 2012, 2012 to 2017 and 2017 to 2022 NAICS, US Census Bureau, accessed 30 October 2026
- North American Industry Classification System (NAICS): FAQs, US Census Bureau, accessed 30 October 2026
- 1997 North American Industry Classification System: 1987 Standard Industrial Classification Replacement (62 FR 17288), Office of Management and Budget, Federal Register, 9 April 1997
- Standard Industrial Classification (SIC) Manual, Occupational Safety and Health Administration, accessed 30 October 2026
- Standard Industrial Classification (SIC) Code List, US Securities and Exchange Commission, 3 June 2021, accessed 30 October 2026
- County Business Patterns methodology, US Census Bureau, accessed 30 October 2026
- 13 CFR 121.402: size standards for federal government contracting programs, Electronic Code of Federal Regulations, accessed 30 October 2026
Written by the Bebop team at Blackpearl Group. Published .
Questions people ask
How do I convert a NAICS code to a SIC code?
Enter the six-digit NAICS code in the converter to see every SIC code that contributed to it, then pick the one whose title and description match your main activity. Many NAICS codes collect pieces of several SIC codes; 238220, for example, draws on 1711, 1791, 1796 and 7699, but most plumbing and HVAC contractors belong in SIC 1711.
Is there an official NAICS to SIC crosswalk?
Yes. The Census Bureau publishes a concordance from the 1987 SIC to 2002 NAICS, which splits each SIC code into pieces and assigns each piece a NAICS code, and it says it has no plans to build others. To reach NAICS 2022 you chain that file through the Census concordances for 2007, 2012, 2017 and 2022, which is what this converter does.
Why does one SIC code match several NAICS codes?
NAICS defines industries more finely and groups some activities differently, so many SIC codes were split. SIC 5812 Eating Places became separate codes for full-service and limited-service restaurants, caterers, food service contractors and others. Later NAICS revisions split some codes again. Of the 1,004 SIC codes, 453 now map to more than one NAICS 2022 code.
What is the SIC code for NAICS 541611?
SIC 8742, Management Consulting Services. In the Census concordance, 541611 takes its content only from 8742. The reverse isn't one to one: SIC 8742 also feeds 541612 human resources consulting, 541613 marketing consulting, 541614 logistics consulting and part of 561312 executive search, so a SIC 8742 company could belong in any of those NAICS codes.
Do I need a SIC code or a NAICS code?
Use NAICS for anything federal: SAM.gov registration, SBA size standards, government bids and Census data. NAICS-based activity codes also go on IRS returns. Use SIC where it's specifically requested, mainly SEC filings and some bank, insurance or supplier forms. If a form doesn't say, NAICS is the current standard, and many forms accept both.