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Allstream Insiders Summary
ONEOK has signed a definitive agreement to acquire Brazos Midstream’s Permian Midland Basin natural gas gathering and processing assets for $4.425 billion in cash. The transaction has not closed. ONEOK currently expects to complete the acquisition during the fourth quarter of 2026, subject to customary closing conditions, including clearance under the Hart-Scott-Rodino Act.
ONEOK said the acquisition would add a Midland Basin system supported by approximately 600,000 dedicated acres under long-term, fixed-fee contracts with a weighted average remaining term exceeding 12 years. The company said the acreage is currently supported by 14 active drilling rigs operated by producers that include ExxonMobil, Diamondback Energy and Double Eagle.
Following completion of the Cassidy II processing plant, which ONEOK currently expects during the third quarter of 2027, the acquired system is expected to include approximately 700 miles of gathering infrastructure and 1.2 billion cubic feet per day of processing capacity across seven core Midland Basin counties.
ONEOK said the acquisition would more than double its Midland Basin processing capacity to approximately 2.3 Bcf/d, including processing plants currently under construction. The company plans to connect the acquired gathering and processing position with its existing Permian Basin natural gas liquids and crude oil infrastructure, including the West Texas NGL Pipeline and the Medford NGL fractionation facility now nearing completion.
The acquisition is expected to be funded through a separate $9 billion nonvoting minority equity investment from funds and affiliates managed by Apollo. ONEOK intends to use approximately $5 billion of those proceeds to reduce existing debt. The Apollo investment is expected to close during the first half of September 2026, subject to customary conditions, while the Brazos acquisition has its own fourth-quarter closing process.
ONEOK-Brazos Transaction Tracker
| Transaction item | Announced detail | Status |
|---|---|---|
| Buyer | ONEOK, Inc. | Definitive agreement signed |
| Assets | Brazos Midstream’s Permian Midland Basin natural gas gathering and processing system | Proposed acquisition |
| Cash consideration | $4.425 billion | Payable at closing |
| Expected acquisition closing | Fourth quarter 2026 | Subject to customary conditions and Hart-Scott-Rodino clearance |
| Acquisition approval | Unanimously approved by ONEOK’s board | Complete |
| Funding | $9 billion nonvoting minority equity investment from Apollo-managed funds and affiliates | Separate agreement; expected to close in first half of September 2026 |
| Planned debt reduction | Approximately $5 billion from Apollo investment proceeds | ONEOK-stated intention |
| Gathering network | Approximately 700 miles | Expected acquired footprint after closing |
| Dedicated acreage | Approximately 600,000 acres under long-term, fixed-fee contracts | ONEOK-reported contract position |
| Contract duration | More than 12 years weighted average remaining term | ONEOK-reported |
| Processing capacity after Cassidy II | 1.2 Bcf/d across seven core Midland Basin counties | ONEOK’s August 30 estimate |
| Expected combined ONEOK capacity | Approximately 2.3 Bcf/d, including plants under construction | Expected after acquisition and current construction program |
What Infrastructure Would ONEOK Acquire from Brazos Midstream?
The proposed acquisition centers on Brazos Midstream’s natural gas gathering and processing platform in the Midland Basin. ONEOK describes the assets as complementary to its existing Permian gathering, processing, NGL transportation and crude oil infrastructure.
The acquired footprint is expected to include:
- Approximately 700 miles of natural gas gathering infrastructure
- Processing capacity expected by ONEOK to reach 1.2 Bcf/d after Cassidy II is completed
- Operations across seven core Midland Basin counties
- Approximately 600,000 dedicated acres under long-term, fixed-fee contracts
- A Midland Basin-wide area of mutual interest with an unnamed private producer
ONEOK said the existing producer base includes ExxonMobil, Diamondback Energy and Double Eagle. The release does not identify the individual contract terms, acreage allocation or throughput contribution associated with each producer.
The asset transfer remains conditional. Until the transaction closes, Brazos Midstream continues to own the system and ONEOK should not be described as having completed the acquisition.
How Does Cassidy II Fit into the Acquisition?
Cassidy II is a 300 MMcf/d cryogenic natural gas processing plant under development at Brazos Midstream’s Cassidy complex in Glasscock County, Texas. Brazos announced the project on August 10, 2026, after previously starting construction of the separate Cassidy I plant at the same complex.
Brazos said Cassidy I is a 300 MMcf/d plant expected to reach mechanical completion in November 2026 and enter service before year-end. Its August 10 announcement described Cassidy II as another 300 MMcf/d plant expected to begin operating in summer 2027.
ONEOK’s August 30 acquisition announcement now identifies the expected Cassidy II completion period as the third quarter of 2027. It also says the Brazos system will have 1.2 Bcf/d of processing capacity following the plant’s completion.
Those figures differ slightly from Brazos’s August 10 announcement, which said Cassidy II would increase total Midland Basin nameplate capacity to approximately 1.1 Bcf/d. The releases do not explain the difference. For accuracy, Allstream attributes the 1.2 Bcf/d figure to ONEOK’s newer acquisition announcement and the 1.1 Bcf/d figure to Brazos’s earlier project announcement.
How Would Brazos Connect with ONEOK’s Existing Permian Infrastructure?
ONEOK expects the acquisition to connect additional Midland Basin gathering and processing volumes with infrastructure it already operates farther downstream. The company specifically identified its West Texas NGL Pipeline and the Medford NGL fractionation facility as assets that could support the combined platform.
ONEOK said the transaction would more than double its Midland Basin processing capacity to approximately 2.3 Bcf/d, including facilities under construction. That figure is an expected post-transaction capacity measure, not current operating capacity available on the closing date.
The company also expects to coordinate commercial, operational and capital activity across the combined footprint. The release does not announce a new interconnecting pipeline, processing plant or fractionator beyond the construction projects already included in the stated capacity figures.
How Is ONEOK Funding the Transaction?
ONEOK plans to fund the acquisition through a $9 billion nonvoting minority equity investment from Apollo-managed funds and affiliates. Apollo would receive a Class B interest in a newly formed holding company, ONEOK Holdings, L.L.C.
ONEOK intends to apply approximately $4.425 billion of the proceeds to the Brazos acquisition and approximately $5 billion toward existing debt. The Apollo investment and the Brazos acquisition are separate transactions with different expected closing periods and conditions.
The Apollo investment is expected to close during the first half of September. The acquisition is expected to close in the fourth quarter following satisfaction of its closing requirements. The announcement does not establish that either closing is certain.
What Could the Transaction Mean for the Midstream Supply Chain?
The immediately confirmed project work is the continued construction of the Cassidy processing plants; the acquisition itself does not constitute a new contractor award or construction authorization. If the transaction closes, ONEOK’s integration of the Brazos system could influence how future gathering, processing and NGL infrastructure is planned across the combined Midland Basin footprint.
Based on the assets and construction program identified in the announcements, relevant work areas could include:
- Cryogenic natural gas processing plant construction and commissioning
- Gathering-pipeline connections and compression
- Electrical, instrumentation and control-system integration
- Plant and pipeline operations and maintenance
- NGL takeaway and downstream-facility coordination
- Capacity optimization across existing and acquired systems
These are potential work areas associated with the disclosed asset configuration. ONEOK did not announce new bid packages, contractor selections or additional final investment decisions as part of the acquisition release.
Allstream Perspective
The proposed acquisition would give ONEOK a substantially larger gathering and processing position in the Midland Basin while linking that position with infrastructure it already operates across the Permian-to-market value chain. The most important physical metric is ONEOK’s expected increase to approximately 2.3 Bcf/d of Midland Basin processing capacity, including projects currently under construction.
The transaction also places additional importance on execution at Cassidy I and Cassidy II. Those plants account for future capacity included in the acquisition narrative, making construction progress and startup timing relevant to the operating scale ONEOK expects to obtain.
For contractors and suppliers, the acquisition does not by itself create a public procurement opportunity. The next decision-useful disclosures would include regulatory clearance, closing of the Apollo investment, completion of the Brazos acquisition, updated Cassidy construction milestones, confirmed interconnection work and any new projects approved after ONEOK integrates the system.
