If you buy natural gas - for industrial processes, power generation, heating, or as a feedstock - and you're located in the mid-Atlantic or Northeast, you've likely noticed that your gas price doesn't always move in sync with the NYMEX Henry Hub price you see quoted in the news. Sometimes your price is much higher. Sometimes it's lower. And sometimes the spread moves dramatically in ways that seem disconnected from the headline commodity market.
What you're experiencing is basis risk. And understanding it is essential for anyone making significant natural gas procurement decisions in this part of the country.
I'm Digby Ferrara, Director of Energy Services at Aggressive Energy, based in Brooklyn, NY. I have worked in natural gas origination across northeastern markets for the better part of two decades. Let me explain what basis is, why it's particularly volatile in the Northeast, and what you can do about it.
Natural gas is priced at dozens of trading locations - called "hubs" - across North America. The NYMEX Henry Hub contract, traded at the Henry Hub in Louisiana, is the benchmark. Every other trading location has a price that is expressed as a differential to Henry Hub - either a premium or a discount.
That differential is basis.
If Henry Hub is trading at $3.00/MMBtu and Transco Zone 6 NY (the hub serving much of the New York metro area) is trading at $3.80, the Transco Zone 6 basis is "+$0.80." If Algonquin Citygate (serving New England) is at $4.50, its basis is "+$1.50."
Basis reflects the local supply and demand fundamentals at a specific location, including transportation costs, pipeline constraints, storage access, and competing sources of supply and demand. It's not random - it's driven by real market conditions.
The northeast natural gas market has undergone a structural transformation over the past 15 years, driven primarily by the Marcellus and Utica shale formations in Pennsylvania, West Virginia, and Ohio. These formations have made the Appalachian basin the largest natural gas producing region in North America.
But there's a paradox. While Appalachian production has surged, the pipeline infrastructure needed to move that gas to major demand centers has lagged. The result: Appalachian basis (the price at producing area hubs like Dominion South or Eastern Gas South) is chronically discounted to Henry Hub - sometimes deeply so - while the pipelines that connect Appalachian supply to New England and New York metro customers are frequently constrained, particularly in winter.
The practical result for mid-Atlantic and Northeast buyers: you can be geographically close to enormous low-cost gas supply but still experience severe price spikes in winter when pipeline infrastructure becomes a binding constraint on what gas can physically reach your city gate.
This is the Northeast basis paradox, and it's been the defining feature of this market for the better part of a decade.
Transco Zone 6 (Non-NY): The delivery point for gas on Transcontinental Gas Pipe Line serving mid-Atlantic markets including Philadelphia, New Jersey, and the greater Delaware Valley. Transco Zone 6 Non-NY is a critical benchmark for local distribution companies and large industrial customers in this region. Its basis can swing dramatically in cold weather as the Transco corridor becomes congested.
Transco Zone 6 NY: The delivery point for Transco service into the New York metro area. Similar dynamics to Zone 6 Non-NY but with additional demand concentration risk.
Algonquin Citygate: The benchmark for New England gas supply. Algonquin is legendary for winter basis volatility - during the polar vortex events of 2014 and 2019, Algonquin basis spiked to extraordinary levels as constrained pipeline capacity met extreme winter demand.
Dominion South / Eastern Gas South: The primary producing area hub for Marcellus/Utica gas. Chronically discounted to Henry Hub, often deeply so in summer and mild-weather periods. Understanding Dominion South basis is essential for anyone with upstream gas exposure or storage arbitrage interests.
Tennessee Gas Pipeline Zone 4 300 Line / Zone 6 200L: Important benchmarks for gas serving the Northeast corridor. Tennessee carries substantial volumes from the Gulf Coast and Appalachia into New England.
From my perspective as a natural gas origination professional in Brooklyn, the current market requires close attention to several dynamics:
Appalachian production growth has moderated. After years of rapid expansion, Marcellus and Utica production growth has slowed as producers respond to price signals and capital discipline. This has tightened the supply picture somewhat and supported Appalachian basis in a way that wasn't the case three years ago.
LNG export demand is a structural change. U.S. LNG export capacity has grown dramatically. This has fundamentally altered the demand picture for domestic natural gas, connecting the U.S. gas market to global LNG price benchmarks in a way that didn't exist 10 years ago. It's made Henry Hub more volatile and has changed the correlations between Henry Hub and northeast basis relationships.
Winter storage risk is not to be ignored. The Henry Hub storage deficit or surplus relative to the 5-year average is a critical input for winter pricing. A winter that begins with below-average storage is a very different risk picture than one that starts with a surplus.
Pipeline capacity additions are worth tracking. Any new Transco, Tennessee, or Columbia Gas lateral capacity into northeast demand markets meaningfully affects basis by relaxing constraints. Tracking FERC certificates and in-service dates for major projects is part of reading the market intelligently.
For commercial buyers with significant gas exposure, basis risk management is not optional. The strategies available include:
Fixed-basis supply contracts. Many retail natural gas supply agreements fix both the NYMEX component and the basis component, giving you certainty on your all-in delivered price. This is appropriate for buyers who want budget certainty and are willing to accept that they might leave money on the table in certain market scenarios.
Index-price supply with basis exposure. Some customers prefer to track NYMEX and accept basis variability - this may make sense if their business economics are correlated to gas prices (e.g., a manufacturer competing against facilities in other regions that face different basis exposures).
Basis swaps. For larger industrial users with treasury sophistication, financial basis swaps can hedge the location differential independently from the commodity price. This gives more flexibility in managing the two components separately.
Physical storage access. Firm storage capacity near demand centers gives a buyer the ability to inject gas during low-basis periods and withdraw during high-basis spikes. For large industrial customers, this is one of the most powerful tools in the toolkit - but it requires scale.
Digby Ferrara is a Director of Energy Services specializing in power and natural gas origination in Brooklyn, NY. He works with commercial and industrial customers across the PJM footprint and northeastern natural gas markets on procurement strategy, structured supply arrangements, and commodity risk management. Contact Digby to discuss your gas procurement strategy.