Company lists · Data refreshed September 2026

Top 25 Oil filled transformer manufacturers based in the United States

RevenueBase identified 290 company matches for oil filled transformer manufacturers associated with the United States as of September 2026 and tracks 20,599 professional contacts across them, including 7,448 with verified work emails. Houston is the largest hub.

This list covers company matches for oil filled transformer manufacturers associated with the United States, found by RevenueBase SmartSearch using the meaning of business descriptions in its company graph at Exact. Ranked by professionals tracked, largest first. Rows show recorded descriptions where available, Exact search membership and the snapshot date. Data refreshed September 30, 2026.

Published by RevenueBase, a B2B data infrastructure company. This list was built with RevenueBase SmartSearch, the natural-language company search RevenueBase customers use to build their own targeted lists and unlock verified emails and direct dials at the companies on them. How these lists are built and judged.

How to read this list RevenueBase SmartSearch · Exact Recorded Sep 30, 2026 How this list was built
290Companies
20,599Contacts tracked
7,448Verified emails
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The 25 largest oil filled transformer manufacturers based in the United States

Ranked by team size
Top 25 of 290 company matches for oil filled transformer manufacturers based in the United States, ordered by professional contacts tracked in RevenueBase, largest first. Recorded Sep 30, 2026. The RevenueBase SmartSearch column shows Exact match membership in this saved search. Click a contact count to view that company's people. Totals use company locations recorded by RevenueBase; the displayed preview is a smaller selection.
#CompanyRevenueBase SmartSearchHeadquartersEmployeesContacts
1Exact matchRosemont, IL, United StatesHQ recorded Sep 30, 202610001+4,259 contacts →

Exact match

“Littelfuse, Inc.(NASDAQ: LFUS) is a diversified, industrial technology manufacturing company shaping solutions for the safe and efficient transfer of electrical energy.”

Recorded in the RevenueBase company graph · Sep 30, 2026 · View company records in RevenueBase
2Exact matchHouston, TX, United StatesHQ recorded Sep 30, 20261,001-5,0002,561 contacts →

Exact match

“Powell is hiring- Powell is dedicated to improving people’s lives by providing reliable power distribution systems in every market we serve.”

Recorded in the RevenueBase company graph · Sep 30, 2026 · View company records in RevenueBase
3Exact matchColumbia, SC, United StatesHQ recorded Sep 30, 20261,001-5,0001,079 contacts →

Exact match

“Hubbell Power Systems (HPS) designs and manufactures a wide variety of electric power transmission, distribution, substation, underground, OEM, and communications products used by…”

Recorded in the RevenueBase company graph · Sep 30, 2026 · View company records in RevenueBase
4Exact matchFremont, CA, United StatesHQ recorded Sep 30, 20261,001-5,000969 contacts →

Exact match

“Industrial Electric Mfg.(IEM) is the largest independent full-line manufacturer of electrical distribution equipment and integrated power systems in the U.S.”

Recorded in the RevenueBase company graph · Sep 30, 2026 · View company records in RevenueBase
5Exact matchWarrendale, PA, United StatesHQ recorded Sep 30, 20261,001-5,000967 contacts →

Exact match

“Mitsubishi Electric Power Products, Inc.(MEPPI) is a leading U.S.”

Recorded in the RevenueBase company graph · Sep 30, 2026 · View company records in RevenueBase
6Exact matchEllisville, MS, United StatesHQ recorded Sep 30, 20261,001-5,000941 contacts →

Exact match

“Howard Industries is the leading manufacturer of liquid-filled distribution transformers for the utility and commercial/industrial markets.”

Recorded in the RevenueBase company graph · Sep 30, 2026 · View company records in RevenueBase
7Exact matchHouston, TX, United StatesHQ recorded Sep 30, 20261,001-5,000928 contacts →

Exact match

“SAE Towers is one of the world’s largest producers of steel lattice towers for high-voltage power transmission.”

Recorded in the RevenueBase company graph · Sep 30, 2026 · View company records in RevenueBase
8Exact matchRoanoke, VA, United StatesHQ recorded Sep 30, 20265,001-10,000792 contacts →

Exact match

“Virginia Transformer is an engineering company that manufactures transformers.”

Recorded in the RevenueBase company graph · Sep 30, 2026 · View company records in RevenueBase
9Exact matchHouston, TX, United StatesHQ recorded Sep 30, 2026501-1,000544 contacts →

Exact match

“Wholesale Electric Supply Company of Houston, Inc.”

Recorded in the RevenueBase company graph · Sep 30, 2026 · View company records in RevenueBase
10Exact matchDyersburg, TN, United StatesHQ recorded Sep 30, 20261,001-5,000520 contacts →

Exact match

“ERMCO (Electric Research and Manufacturing Cooperative, Inc.) is headquartered in Dyersburg, Tennessee.”

Recorded in the RevenueBase company graph · Sep 30, 2026 · View company records in RevenueBase
11Exact matchGreer, SC, United StatesHQ recorded Sep 30, 2026201-500286 contacts →

Exact match

“Maddox serves the commercial, industrial, utility, and renewables segments of the transformer market.”

Recorded in the RevenueBase company graph · Sep 30, 2026 · View company records in RevenueBase
12Exact matchKansas City, MO, United StatesHQ recorded Sep 30, 2026501-1,000266 contacts →

Exact match

“Milbank provides the tools that empower life.”

Recorded in the RevenueBase company graph · Sep 30, 2026 · View company records in RevenueBase
13Exact matchBristol, VA, United StatesHQ recorded Sep 30, 2026501-1,000221 contacts →

Exact match

“Electro-Mechanical, LLC is a global leader in developing and manufacturing technologies used for electrical power distribution switching, power quality and power protection…”

Recorded in the RevenueBase company graph · Sep 30, 2026 · View company records in RevenueBase
14Exact matchPrice, UT, United StatesHQ recorded Sep 30, 2026501-1,000208 contacts →

Exact match

“IE provides custom-engineered, packaged equipment to industrial markets.”

Recorded in the RevenueBase company graph · Sep 30, 2026 · View company records in RevenueBase
15Exact matchMontgomery, AL, United StatesHQ recorded Sep 30, 2026201-500202 contacts →

Exact match

“HD Hyundai Power Transformers USA, Inc, a subsidiary of HD Hyundai Electric Systems, stands as a premier transformer manufacturer located in Montgomery, Alabama.”

Recorded in the RevenueBase company graph · Sep 30, 2026 · View company records in RevenueBase
16Exact matchBordentown, NJ, United StatesHQ recorded Sep 30, 2026201-500177 contacts →

Exact match

“NWL Inc.”

Recorded in the RevenueBase company graph · Sep 30, 2026 · View company records in RevenueBase
17Exact matchAthens, GA, United StatesHQ recorded Sep 30, 20261,001-5,000174 contacts →

Exact match

“Power Partners is a leading manufacturer of distribution transformers in North America.”

Recorded in the RevenueBase company graph · Sep 30, 2026 · View company records in RevenueBase
18Exact matchCanonsburg, PA, United StatesHQ recorded Sep 30, 2026201-500169 contacts →

Exact match

“Pennsylvania Transformer Technology LLC (PTT) is a US-owned, industry leading manufacturer of a wide range of sizes and types of power transformers for the investor-owned…”

Recorded in the RevenueBase company graph · Sep 30, 2026 · View company records in RevenueBase
19Exact matchFranklin Park, IL, United StatesHQ recorded Sep 30, 2026501-1,000165 contacts →

Exact match

“For over 100 years, SAI (Switchboard Apparatus, Inc.) has supplied innovative and reliable equipment for electrical power distribution.”

Recorded in the RevenueBase company graph · Sep 30, 2026 · View company records in RevenueBase
20Exact matchSolomon, KS, United StatesHQ recorded Sep 30, 2026501-1,000157 contacts →

Exact match

“Solomon Corporation buys, sells, repairs, recycles, and disposes of transformers, regulators and reclosers.”

Recorded in the RevenueBase company graph · Sep 30, 2026 · View company records in RevenueBase
21Exact matchVernon, CA, United StatesHQ recorded Sep 30, 2026201-500147 contacts →

Exact match

“MGM Transformers is now part of Forgent Power Solutions.”

Recorded in the RevenueBase company graph · Sep 30, 2026 · View company records in RevenueBase
22Exact matchOklahoma City, OK, United StatesHQ recorded Sep 30, 2026201-500145 contacts →

Exact match

“In 2025, Southwest Electric Co.”

Recorded in the RevenueBase company graph · Sep 30, 2026 · View company records in RevenueBase
23Exact matchMckinney, TX, United StatesHQ recorded Sep 30, 2026201-500138 contacts →

Exact match

“Emerald Transformer is the premier national single-source solution for oil-filled electrical equipment with services including repair, re-manufacturing, field technical services…”

Recorded in the RevenueBase company graph · Sep 30, 2026 · View company records in RevenueBase
24Exact matchCaldwell, ID, United StatesHQ recorded Sep 30, 20261,001-5,000136 contacts →

Exact match

“Mission Critical Group (MCG) stands apart as an end-to-end power systems and solutions provider, accelerating time-to-power in mission critical environments with unmatched speed…”

Recorded in the RevenueBase company graph · Sep 30, 2026 · View company records in RevenueBase
25Exact matchLake Mary, FL, United StatesHQ recorded Sep 30, 2026201-500134 contacts →

Exact match

“At JST Power Equipment, we pride ourselves on delivering world-class transformer and electrical equipment solutions.”

Recorded in the RevenueBase company graph · Sep 30, 2026 · View company records in RevenueBase

Showing 25 of 290 oil filled transformer manufacturers based in the United States

See the full list, filter by size, metro and specialty, and access 7,448 tracked professional contacts with verified work emails. Direct dials are available where recorded.

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Oil filled transformer manufacturers based in the United States at a glance

As of Sep 30, 2026
36.2%Verified-email coverage
71.0Average contacts per company
11-50Median size (employees)
6.6%Largest-city concentration · Houston
Sep 30, 2026Page data refreshed

Companies by employee count

1-10
85
11-50
90
51-200
57
201-500
23
501-1,000
15
1,001-5,000
16
5,001-10,000
2
10001+
2

Email recency for this list is measured worldwide rather than for United States, so it is reported there. Company counts and contact totals on this page are exact for United States, over 290 companies.

How this list was built

The recorded descriptions help you assess these company matches. Check a company’s website for its current services and locations.

Source
The RevenueBase company graph: 60 million companies and 398.9 million professional contacts resolved from primary sources, queried with RevenueBase SmartSearch, the natural-language company search available to every RevenueBase user.
What qualifies
Company records associated with the United States whose business descriptions match “oil filled transformer manufacturers” by meaning at the Exact setting. Descriptions are compiled in the RevenueBase company graph from public websites, profiles and company information where available; they are not guaranteed quotations from the company's website.
RevenueBase SmartSearch
Describe a niche company in your own words to find businesses by meaning. Exact, Similar, Related and Broad control the breadth of RevenueBase SmartSearch. This saved list uses Exact. Each row's Exact match badge shows inclusion in that search, not an individual score or a service-quality judgment.
Public preview
The public preview omits records without a verified work email. Where headquarters information is recorded, preview rows are also filtered to this page’s location. Dataset totals and geographic summaries describe the full matched records before these preview filters.
Match quality
RevenueBase's August 25, 2026 study assessed 4,198 description/company pairs across matching settings. The publisher reports 86% good or better at Exact. This evaluates the method across queries; it does not audit this individual list. Recorded company descriptions, where available, help you judge each match yourself. Read the full methodology: how the lists are built and what the study measures.
Ranking
Team size, largest first: companies are ordered by the number of professionals RevenueBase tracks at each one. Employee ranges shown are reported bands, for context.
Verification
Every displayed company carries at least one verified work email. RevenueBase tracks 7,448 professional contacts with verified work emails across the full matched dataset. Contacts re-verify on a rolling cadence, and each contact's own verification date is shown inside RevenueBase.
Refresh
This page's figures were pulled from the company graph on September 30, 2026. Lists refresh periodically as the graph is re-checked.
Record context
Company records and descriptions can change. Check the company's website for its current services and locations.

Frequently asked

What is RevenueBase SmartSearch?

RevenueBase SmartSearch finds niche companies by the meaning of their business descriptions in the RevenueBase company graph. Exact, Similar, Related and Broad control how closely companies must fit your description. This list uses Exact for “oil filled transformer manufacturers”; each Exact match badge shows search membership, not an individual similarity or quality score.

How many oil filled transformer manufacturers are there based in the United States?

RevenueBase identified 290 company matches for oil filled transformer manufacturers associated with the United States as of September 2026, using the meaning of business descriptions at Exact. This is the recorded matched set in the RevenueBase company graph.

What is the largest company on this list?

Littelfuse tops the displayed preview by professional contacts tracked in RevenueBase. Recorded headquarters appear in the company rows.

Which city has the most oil filled transformer manufacturers?

Houston leads with 19 company records, followed by Canton (4) and Cincinnati (4).

How do I get contact information for these companies?

A free RevenueBase account lets you run this exact search and work limited free results with 500 credits to start. Upgrading provides access to the 7,448 professional contacts with verified work emails tracked across these 290 companies; direct dials are available where recorded.

How current is this list?

The list refreshes periodically as the company graph is re-checked. This page's figures were pulled on September 30, 2026.

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About this data

RevenueBase is a B2B data infrastructure company. Its company graph covers 60 million companies and 398.9 million professional contacts, with emails verified on a rolling cadence rather than scraped once and left to decay. These company lists are generated directly from that graph with RevenueBase SmartSearch, the same natural-language company search every RevenueBase user has: describe a market in plain words, get the companies that match, and add verified emails and direct dials for the people at them. It is the same data that powers RevenueBase's B2B data products, and a free account includes 500 credits to start. How these lists are built and judged.