How to Find Companies With 401(k) Plans, and Filter Them by Industry (NAICS) Code

Sources: EFAST2 Form 5500 Search, the DOL 2025 Instructions for Form 5500 (line 2d and business codes), and the DOL Form 5500 Datasets page (observed 2026-10-05).

A note on who this is for. If you are an employee or job seeker looking for an employer with a good 401(k), or for an old account of your own, this is not that guide. This one is for advisors, TPAs, and wholesalers prospecting the employers that sponsor plans. For you, a list of companies with 401(k) plans is neither a secret nor a purchase. It is a federal filing, and the government publishes it with filters attached.

How many companies have 401(k) plans?

Two practical consequences. Plans are not quite the same as companies: an employer can sponsor more than one plan, which is why every filing pairs the EIN with a three-digit plan number. And most 401(k) sponsors are small employers, so a search that returns thousands of rows for your area is working correctly.

Method 1: Filter the DOL's EFAST2 search by plan type, industry, and place

• Open the EFAST2 Form 5500 Search and choose Show Filters. When we reviewed it on 2026-10-05, the filter panel offered plan years, defined contribution pension types, assets, participants, employer plan types, business codes, state, ZIP code, and form years, plus an Export to CSV button for results. No account is required.
• Pick a plan year. Recent years keep filling in as late and extended returns arrive, so the latest year may be incomplete for months.
• Under defined contribution pension types, select 2J, "Code section 401(k) feature." That is the DOL's code for a 401(k) cash-or-deferred arrangement. It is different from 2E (profit-sharing) and 2S (automatic enrollment), which can appear on the same plan.
• Under business codes, pick a sector or enter a code range. Sectors follow NAICS, such as Health Care and Social Assistance or Construction; a range lets you go down to six digits.
• Add state or ZIP, then assets and participants. Size filters separate a five-person practice from a 300-employee manufacturer.
• Export, then deduplicate. Results are filings, not companies. Collapse amended returns and keep one row per EIN and plan number.

Source: EFAST2 Form 5500 Search filter labels and the 2025 Instructions for Form 5500, plan characteristic codes (observed 2026-10-05).

How NAICS business codes work on the Form 5500

Line 2d asks for the six-digit business code that best describes the primary nature of the plan sponsor's business; for a multiemployer plan, it is the predominant industry of the active participants. The code list sits at the back of the instructions, and the DOL notes that "these principal activity codes are based on the North American Industry Classification System." Because the sponsor picks its own code, treat it as self-reported: a dental group might choose the dentist code or a broader health care code, so search a range when you can.

Source: DOL, 2025 Instructions for Form 5500, Codes for Principal Business Activity and the EFAST2 Form 5500 Search business-code filter (observed 2026-10-05).

Method 2: Download the DOL datasets and filter by NAICS yourself

If you work in large spreadsheets or code, the DOL's Form 5500 Datasets page publishes the Form 5500 and Form 5500-SF filings and each schedule as annual files, with data dictionaries and file layouts, and says the 2009-and-later datasets are typically updated around the first of each month. The main filing files carry the sponsor's business code, address, and plan characteristic codes, so every 401(k) sponsor in your state within one NAICS range is a filter, not a purchase.

The cost is the joining. Assets, providers, and compliance answers sit in separate schedule files, amended returns sit beside originals, and the files refresh monthly. That is the work paid tools charge for, ours included.

Method 3: Start from a ZIP code instead

If your market is a territory rather than an industry, start with geography and add industry second. The free steps for that are in how to find 401(k) plans by ZIP code.

What a list of companies with 401(k) plans can't tell you

The truth is, the list is the easy part. Every advisor in your market can pull the same 2J-filtered, NAICS-filtered export in an afternoon, and it comes back in no useful order. It also describes the past: a return is due by the last day of the seventh calendar month after the plan year ends, plus up to two and a half months on extension, so the newest complete year always trails the calendar. A list tells you who sponsors a 401(k) plan. It does not tell you which sponsor is open to a conversation this quarter, or what to say when you reach them.

Source: DOL, 2025 Instructions for Form 5500 (When To File; Form 5558 extension) (observed 2026-10-05).

Where FiduciarySignal fits

Full disclosure, this part is ours, and it is paid. FiduciarySignal's Change Predictor takes a ZIP code, radius, or state and ranks the plans in that territory by the odds of a winnable provider change (trustee, custodian, recordkeeper or administrator), back-tested against the next year's Form 5500 filings and strongest at the top of the list. It deals in calibrated likelihoods, never certainty. The 401(k) Report Card then grades any plan from its own filing: administrative cost against comparable peers, participation, red flags, and the provider roster. FiduciarySignal is $90 per month after a seven-day free trial, or $900 per year, built on public DOL EFAST2 data and not affiliated with the Department of Labor. To see one ranked result before deciding anything, the free signal page returns one live switch signal from your ZIP, no card.

Related guides

• How to Find 401(k) Plans by ZIP Code (Free, Step by Step)
• Form 5500 Search: The Free Tools, Step by Step — and the One Thing a Filing Can't Tell You
• How to Prospect 401(k) Plans: The Six-Step Process