Mont Belvieu TET vs non-TET propane: what the OPIS labels mean

TET and non-TET are not grades of propane. They are storage systems inside the Mont Belvieu hub in Texas, and OPIS, the price-reporting agency, publishes a separate daily price for propane in each: TET for the original Texas Eastern storage location, now owned by Energy Transfer and also quoted as LST (for Lone Star), and non-TET for Enterprise Products Partners' Mont Belvieu storage. The label marks where a barrel sits, and the gap between the two prices is what the market pays for that location on a given day.

Where the TET name comes from

TET stands for Texas Eastern Transmission Corporation. Its products-pipeline company, TEPPCO (Texas Eastern Products Pipeline), ran a large propane storage facility at Mont Belvieu and the pipeline that carried propane from there north through Ohio into New York, Pennsylvania and Illinois. In its 2006 case against BP, the Commodity Futures Trading Commission defined TET propane as propane deliverable at the TEPPCO storage facility or anywhere in the TEPPCO system, and non-TET propane as propane stored at the other Mont Belvieu facilities, then run by Enterprise and Dynegy.

The same case shows that TET trades as a market of its own. The CFTC found that BP cornered the TET propane market in February 2004, and in 2007 BP paid about $303 million in combined civil and criminal sanctions. A squeeze on propane deliverable at one storage location moved that location's price, which is the whole reason the labels exist.

Why TET now means Energy Transfer

The owners changed and the label stayed with the storage. TEPPCO sold its interest in the Mont Belvieu storage partnership to Louis Dreyfus in 2007. In 2011, Louis Dreyfus Highbridge Energy's midstream business, Mont Belvieu storage included, went to Lone Star NGL, a joint venture of Energy Transfer Partners and Regency Energy Partners that is part of Energy Transfer today. TEPPCO itself became part of Enterprise in 2009. So the TET name sits on storage Energy Transfer owns, while Enterprise, which owns what was TEPPCO, trades its own Mont Belvieu storage as non-TET.

Each owner's name became another label for the same place. CME's physically delivered TET propane future delivers at what its rulebook calls the Lonestar NGL Energy Transfer facility, formerly Louis Dreyfus Highbridge (LDH), and CME's TET contracts were titled Mont Belvieu LDH Propane (OPIS) before CME renamed them TET. Nasdaq's 2016 Mont Belvieu LST Propane future settled on the OPIS TET price. TET, LDH and LST all point at one storage location.

The three Mont Belvieu propane prices

OPIS splits the hub three ways, by storage operator:

• TET: propane traded in the original TET storage location, owned today by Energy Transfer. Also seen as LST, ETR or, in older contract names, LDH.
• Non-TET: propane traded in Mont Belvieu Caverns, the Enterprise Products Partners storage subsidiary, and only there. Also seen as ENT.
• Other Non-TET: propane traded in Targa Resources' storage at the hub.

Each is quoted in cents per gallon for "any current month" delivery, meaning buyer and seller agree the propane can move at any time within the calendar month. A "wet" barrel, by contrast, carries a specific delivery date.

How the labels show up in futures

The labels matter most in contracts that settle on OPIS prices. ICE lists a cash-settled future on each: Propane, OPIS Mt. Belvieu TET (symbol PRL), Non-TET (PRN) and Other Non-TET (PBO), each 1,000 barrels, or 42,000 gallons, and each settled on the month's average of the OPIS daily price. ICE's name for the non-TET reference price, "NGL-MONT BELVIEU PROPANE (NON-TET)-OPIS," is the long label that turns up in contract documents. CME lists Mont Belvieu TET Propane (OPIS) and Mont Belvieu Non-TET Propane (OPIS) futures as well.

Because the two prices can separate, the label on a hedge is a basis question. A dealer that buys physical propane priced off Enterprise but hedges with a TET-settled contract collects on one storage system's price while paying on the other's. Writing in LP Gas magazine in October 2024, Mark Rachal of Cost Management Solutions noted that most propane swaps have historically settled against TET, which works most of the time because the spread between the pricing points is usually narrow and the prices move in tandem.

What the spread between TET and non-TET reflects

Since the label marks a place rather than a quality, the gap between TET and non-TET is the price of location inside the hub. Each storage system is tied to its owner's fractionators, pipelines and docks. Enterprise loads LPG for export at its terminals on the Houston Ship Channel. Energy Transfer moves export-grade propane from its Mont Belvieu storage and fractionation complex by pipeline to its marine terminal at Nederland, Texas, per the two companies' annual reports. When one system's way out slows and propane backs up behind it, that system's price falls against the other until the barrels move again.

Worked example: the fall of 2024

Maintenance at Energy Transfer's Nederland export terminal ran past the end of September 2024, and LP Gas magazine reported compressor problems when it restarted. Unable to export for weeks, Energy Transfer was, in the magazine's words, "awash with propane." TET traded as much as 19 cents a gallon below non-TET intraday in September. The gap narrowed to 4 cents in October, then widened again to 10.25 cents in the days before the article ran on October 28.

Set those figures against EIA's own Mont Belvieu series, the line charted above. EIA's daily spot price ranged from 58.8 to 73.5 cents a gallon in September 2024, so a 19-cent gap inside the hub was between a quarter and a third of the hub price itself. On October 28, 2024, EIA's spot price was 74.5 cents and EIA's survey put the US residential price that week at $2.430, a gap of $1.685 from hub to home. The 10.25-cent spread between storage systems was about 6 percent of that. A swing that rewrites an exporter's margin is a small slice of a delivered gallon, because most of the residential price is built after the propane leaves the hub.

Reading TET and non-TET next to EIA's spot price

EIA publishes a single daily Mont Belvieu propane price, sourced from Refinitiv, an LSEG business, and its definition names only the location: propane for delivery in Mont Belvieu, Texas. The definition does not name a storage system, so read the EIA figure as the hub-level benchmark rather than as either OPIS assessment. EIA's weekly, monthly and annual figures are simple averages of the daily closing prices. The OPIS assessments are sold by subscription and The Fill Line does not republish them; when one is quoted, the two things to check are the storage system named and the delivery timing.

From the hub to the tank

Whichever system a barrel starts in, the path to a home is the same: the hub price, then pipeline, rail or truck to a regional terminal where the wholesale, or rack, price is set, then the retailer's delivery, tank and service costs. How propane is priced walks through each layer, and the Mont Belvieu spot price page measures the full distance from hub to residential price week by week through the heating season. EIA's latest daily reading puts Mont Belvieu propane at $0.919/gal on Oct 6, 2026.

The table above is the national residential price from EIA's weekly survey, which runs October through March.

The Fill Line is a free weekly read of the public propane numbers: the state price survey from October through March, and stocks, the Mont Belvieu spot and the weekly supply balance year round. One email a week on what moved.