Natural gas NYMEX last day settlement: Always much ado about something

In energy markets, there are several ways to determine how to set the price of natural gas. Within those options, a buyer can choose to fix a price, or peg it to any one of a multitude of published indices used to set the contractual price. If a buyer elects a buying strategy that does not fix the price, the price paid defaults to an index, or market-based price. Simply put, if the price isn’t protected in some way with a different price structure, “index happens.”  

By far the most common natural gas index chosen in U.S. markets, and for a growing number of international buyers of U.S. natural gas, is the New York Mercantile Exchange (NYMEX) benchmark settlement location in Henry Hub, Louisiana. Three business days prior to the end of each month, the Last Day Settlement (LDS) NYMEX benchmark price for the upcoming month is determined, and anyone with a NYMEX LDS indexed price contract will know and then receive the LDS price of gas for the next month.  

On January 28, 2026, three business days prior to the end of the month, the February 2026 NYMEX contract went to final settlement at a price of $7.46/MMBtu, and all contracts with a NYMEX LDS structure were tied to that price. The chart below puts the historical context of this price in place, with the February 2026 LDS on the far right. 

There has not been a NYMEX LDS price higher for any month since September 2022, the year in which Russia invaded Ukraine. The last time NYMEX had a February LDS higher than $7.46/MMBtu was in 2008, with a price of $7.996, some eight years before the U.S. became a net exporter of LNG. 

As the last quarter century of last day settlements shows, volatility is neither new nor one-sided: it can be extreme in both low- and high-price regimes. We can usually identify after-the-fact drivers of sharp moves, but they were not predictable in real time. Most recently, Winter Storm Fern hit as the NYMEX LDS was set, spiking the last day settlement. Just seven NYMEX trading sessions earlier, the February 2026 contract closed $4.36 lower, at $3.10/MMBtu.  

Price volatility has risen as U.S. natural gas becomes more globally exposed through pipeline and LNG exports. That exposure has attracted both private equity and international buyers that are trying to protect the NYMEX LDS benchmark price to which their gas is now tied. The volatility caused by this growing number of interested parties is also attracting more speculative trading, which adds more fuel to the fire, amplifying the impact. Understanding the growing risk of new interested parties and the impacts on U.S. natural gas markets is vital. Those who ignore this risk are effectively choosing to let index happen, rather than managing it.