The ten largest US midstream companies in 2026 operate a combined network spanning more than 500,000 miles of pipeline, hundreds of processing plants, and storage capacity exceeding one billion barrels of liquid hydrocarbon equivalents. They sit between the wellhead and the end customer — gathering, processing, transporting, and storing natural gas, natural gas liquids (NGLs), crude oil, and refined products at industrial scale. The sector has consolidated significantly since 2022, driven by ONEOK’s $18.8bn acquisition of Magellan Midstream Partners, Energy Transfer’s continued expansion, and Williams Companies’ deepening position in natural gas transmission. What follows is a ranked guide to the ten most significant US midstream companies by network scale and throughput in 2026.
How We Ranked the Top 10 US Midstream Companies
Rankings are based on total pipeline network mileage, processing capacity, storage capacity, and annual revenue — weighted toward network scale and throughput rather than market capitalisation alone. All ten companies are US-headquartered or US-primary operators. Canadian-headquartered companies with significant US operations (Enbridge, TC Energy) are noted where relevant but ranked on their US network contribution rather than global scale. Revenue figures are drawn from most recent annual reports and Q4 2025 earnings disclosures.
Top 10 US Midstream Companies in 2026
1. Enterprise Products Partners — Texas
Enterprise Products Partners is the largest US midstream company by total asset scale, operating approximately 50,000 miles of pipeline across natural gas, NGL, crude oil, refined products, and petrochemical service. Its NGL pipeline and fractionation network — centred on the Mont Belvieu, Texas hub — is the largest of its kind in the world, handling approximately 6 million barrels per day of NGL volumes. Enterprise’s 2025 revenue exceeded $50bn, and its integrated asset base — spanning gathering, processing, transportation, fractionation, storage, and marine terminal operations — gives it the broadest single-company midstream footprint of any operator in the US market. Enterprise is structured as a master limited partnership (MLP) and has paid consecutive quarterly distributions since its 1998 IPO.
2. Energy Transfer — Texas
Energy Transfer operates one of the most geographically extensive midstream networks in the US, with approximately 125,000 miles of pipeline across natural gas, crude oil, NGLs, and refined products. Its asset base spans 41 states, anchored by the Panhandle Eastern Pipe Line, Rover Pipeline, and the Dakota Access Pipeline (DAPL) — which alone transports approximately 570,000 barrels per day of Bakken crude to Patoka, Illinois. Energy Transfer’s 2025 revenue exceeded $80bn, reflecting its diversified exposure across commodity types and geographies. The company’s aggressive acquisition history — including the $7.2bn acquisition of Enable Midstream in 2021 — has made it the second-largest US midstream operator by pipeline mileage.
3. ONEOK — Oklahoma
ONEOK executed the most transformative US midstream acquisition in a decade when it closed the $18.8bn purchase of Magellan Midstream Partners in September 2023, adding 9,500 miles of refined products pipeline and 54 terminals to its existing natural gas and NGL network. The combined entity operates approximately 50,000 miles of pipeline across natural gas gathering and processing, NGL gathering and distribution, and refined products transportation — making ONEOK a genuinely multi-commodity midstream operator for the first time. Its subsequent acquisition of Medallion Midstream for $2.6bn added 3,000 miles of Permian Basin crude gathering pipeline, further extending its upstream gathering reach into the most prolific US oil basin.
4. Williams Companies — Oklahoma
Williams Companies is the dominant US natural gas transmission operator, with its Transco pipeline system — stretching 1,800 miles from the Gulf Coast to New York — carrying approximately 15% of all US natural gas consumption on peak demand days. Williams operates approximately 33,000 miles of pipeline in total, with its gathering and processing operations in the Haynesville, Marcellus, Utica, and DJ Basin complementing Transco’s long-haul transmission role. Williams reported 2025 revenues of approximately $10.9bn. Its strategic focus on natural gas — and the growing role of gas in backing US power generation and LNG export demand — positions it as the most structurally aligned of the major US midstream companies to the long-term gas demand outlook.
5. Kinder Morgan — Texas
Kinder Morgan operates approximately 79,000 miles of pipeline and 139 terminals, making it one of the largest energy infrastructure operators in North America by asset count. Its network spans natural gas transmission, CO₂ transportation, refined products pipelines, and liquid terminal storage — with particular concentration on the US Gulf Coast and Southeast. Kinder Morgan’s terminal division operates bulk liquid storage capacity at major ports including Houston, Galveston, and the Port of Los Angeles. In 2026, the company is co-developing the Western Gateway Pipeline with Phillips 66 — a binding open season project targeting refined products transportation from the Permian Basin to West Texas markets.
Full profile: Kinder Morgan Inc: North America’s Pipeline & Terminals Giant 2026.
6. Targa Resources — Texas
Targa Resources is the leading pure-play NGL and natural gas gathering and processing operator in the Permian Basin, with approximately 38,000 miles of pipeline and processing capacity exceeding 7 billion cubic feet per day (Bcf/d). Its Grand Prix NGL Pipeline — running from the Permian and STACK/SCOOP plays to Mont Belvieu — is one of the most strategically positioned NGL transportation assets in the US midstream sector. Targa reported 2025 revenues of approximately $17bn. Its Permian Basin concentration gives it direct exposure to the highest-growth upstream production basin in the US, with volume growth driven by Permian operator drilling programmes rather than market share competition.
7. Plains All American Pipeline — Texas
Plains All American Pipeline operates approximately 18,000 miles of crude oil and NGL pipeline, with particular concentration in the Permian Basin, Western Canada, and the US Gulf Coast. Its acquisition of EPIC Crude Pipeline for $2.9bn in 2025 added 730 miles of Permian Basin crude takeaway capacity, reinforcing its position as the largest crude oil pipeline operator in the Permian. Plains reported 2025 revenues of approximately $48bn, though the majority reflects commodity throughput value rather than fee-based margin — a structural distinction from the predominantly fee-based models of Enterprise, Williams, and Kinder Morgan.
8. Phillips 66 Midstream — Texas
Phillips 66 operates one of the largest integrated midstream businesses among the US refining majors, with its DCP Midstream acquisition (closed 2023) adding approximately 57,000 miles of gathering and transportation pipeline to its existing NGL and refined products network. Phillips 66 Partners — the MLP vehicle through which midstream assets were previously held — has been fully consolidated into the parent company. Its midstream segment handles NGL fractionation, natural gas gathering and processing, crude oil transportation, and refined products pipeline operations across the US Gulf Coast, Rockies, and Midcontinent regions.
Full profile: Phillips 66: Refining, Midstream & Chemicals Profile 2026.
9. NorthStar Midstream — North Dakota
NorthStar Midstream is a Bakken-focused gathering and processing operator whose asset base was built through the acquisition of Bayou Midstream’s Bakken infrastructure in 2024. Its gathering system serves oil and gas producers across the North Dakota Williston Basin — one of the most active US shale plays outside the Permian — with pipeline, compression, and gas processing infrastructure designed to handle the associated gas volumes produced alongside Bakken crude. NorthStar’s scale is significantly smaller than the publicly traded operators above it in this ranking, but its Bakken concentration and the strategic value of dedicated gathering infrastructure in a maturing basin make it a relevant regional operator in the US midstream landscape.
Full profiles: NorthStar Midstream: Bakken Assets & Bayou Acquisition and Bayou Midstream: Bakken Build & 2024 Exit to Bridger.
10. Enbridge US Operations — Texas / Illinois
Enbridge, while Canadian-headquartered, operates the single most consequential piece of crude oil midstream infrastructure in the United States — the Lakehead Pipeline System, which forms the US portion of the Enbridge Mainline and carries approximately 3 million barrels per day of Canadian crude and NGLs from the Canadian border to refinery markets in the US Midwest and Gulf Coast. Enbridge’s 2023 acquisition of three US Gulf Coast gas utilities from Dominion Energy added regulated gas distribution infrastructure in Ohio, Utah, and Wyoming to its existing US pipeline network. Its US asset base — valued at well over $30bn — justifies inclusion in any ranking of the most significant US midstream companies by network impact, regardless of corporate domicile.
What’s Shaping US Midstream in 2026
Three forces are defining the competitive landscape among US midstream companies in 2026. First, Permian Basin volume growth continues to drive capital allocation — every major operator with Permian exposure is expanding gathering, processing, and takeaway capacity to keep pace with producer drilling programmes. The basin’s output is expected to exceed 6.5 million barrels per day by end-2026, creating sustained demand for additional pipeline infrastructure.
Second, LNG export demand is reshaping natural gas transmission economics. Williams’ Transco, Kinder Morgan’s Gulf Coast network, and Energy Transfer’s pipeline assets are all positioned to benefit from the structural increase in Gulf Coast gas demand driven by Sabine Pass, Corpus Christi, Port Arthur, and Plaquemines LNG export terminals reaching full capacity. The midstream sector is the direct transmission infrastructure beneficiary of the US LNG export buildout.
Third, energy transition obligations are creating a new capital allocation category for every major operator — CO₂ transportation for carbon capture projects, hydrogen blending pilots in gas transmission infrastructure, and renewable natural gas (RNG) injection into existing pipeline systems. None of these transition segments generates material revenue in 2026, but all require infrastructure investment decisions being made now.
For the global midstream context, see the Top 10 Midstream Companies 2026: $80bn Networks Ranked. The pipeline infrastructure underpinning these networks is covered in the Top 10 Pipeline Companies in 2026: The Global Energy Arteries.
What is the largest US midstream company in 2026?
Enterprise Products Partners is the largest US midstream company by total asset scale, operating approximately 50,000 miles of pipeline and the world’s largest NGL fractionation and transportation network centred on Mont Belvieu, Texas. ONEOK and Energy Transfer are close competitors by pipeline mileage following their respective major acquisitions since 2022.
What does a US midstream company do?
US midstream companies gather, process, transport, and store oil, natural gas, and natural gas liquids (NGLs) between upstream production sites and downstream refineries, export terminals, utilities, and end consumers. Their infrastructure includes gathering pipelines from wellheads, gas processing plants that separate NGL from natural gas, long-haul transmission pipelines, fractionation facilities that separate NGL streams, and bulk liquid storage terminals at market hubs and ports.
How has ONEOK’s acquisition of Magellan changed the US midstream landscape?
ONEOK’s $18.8bn acquisition of Magellan Midstream Partners in September 2023 was the largest US midstream transaction in a decade. It transformed ONEOK from a predominantly NGL and natural gas operator into a multi-commodity midstream company with 9,500 miles of refined products pipeline, 54 terminals, and significant crude oil gathering capacity. The deal effectively removed Magellan — previously the largest US refined products pipeline operator — as an independent entity and concentrated refined products transportation further among a smaller number of large integrated operators.
What is the difference between a pipeline company and a midstream company?
Pipeline companies are a subset of the midstream sector — they specifically own and operate the transmission and gathering pipelines that move hydrocarbons between production areas and market hubs. Midstream companies typically integrate pipeline operations with gas processing, NGL fractionation, storage, and terminal operations. The largest US midstream companies — Enterprise, Energy Transfer, ONEOK, Williams — own pipelines but derive revenue from the full midstream value chain rather than transportation tariffs alone.
Why are US midstream companies important for LNG exports?
US LNG export terminals on the Gulf Coast require a continuous and reliable supply of natural gas at volumes that only the major interstate pipeline systems can deliver. Williams’ Transco pipeline, Kinder Morgan’s Gulf Coast Express, and Energy Transfer’s network of Gulf Coast gas pipelines are the physical infrastructure connecting Appalachian, Haynesville, and Permian gas production to LNG liquefaction facilities at Sabine Pass, Corpus Christi, Port Arthur, and Plaquemines. Without midstream pipeline capacity, US LNG export capacity cannot be utilised regardless of liquefaction plant availability.