ExxonMobil Sanctions $12.5bn Longtail Gas Development Offshore Guyana

ExxonMobil has sanctioned a $12.5bn investment in Longtail, the eighth development on Guyana's Stabroek block, with first production targeted for 2030. The final investment decision (FID), taken through subsidiary ExxonMobil Guyana, shifts the block's focus for the first time squarely onto non-associated gas (gas produced without oil) and condensate-rich resources.

Longtail sits in the south-eastern corner of Stabroek. The development plan calls for a floating production, storage and offloading vessel — the FPSO — rated at 1.2 billion standard cubic feet of gas per day and up to 250,000 barrels of condensate daily. Roughly 45 subsea production and injection wells will support the scheme.

That is a large well count. It signals sustained rig demand in the basin well into the next decade, though Exxon has not detailed the drilling schedule or contractor lineup. Takeaway: Longtail is a gas-scale project bolted onto an oil machine.

Who holds what in Stabroek?

ExxonMobil Guyana operates the block with a 45% interest. Hess Guyana Exploration holds 30% and CNOOC Petroleum Guyana holds 25%. The structure is unchanged from prior projects.

Current output from Stabroek runs at about 900,000 barrels of oil per day (bopd) across four producing developments. Exxon expects production to exceed one million barrels per day after the Uaru project starts up in the fourth quarter of 2026.

What does the pipeline option mean?

Longtail is designed to process gas and condensate offshore. But Exxon notes the potential to move gas to shore by pipeline — conditional on future investment decisions, market needs, and the establishment of supporting infrastructure. That is not a sanction. It is an option, and Exxon has not costed it or timed it.

Guyana has long debated monetizing associated gas onshore for power and petrochemicals. The Longtail FID does not settle that debate. Read the caveat plainly: shore-side gas remains speculative until someone funds a pipeline.

How full is the project queue?

Construction continues on Whiptail and Hammerhead, the block's sixth and seventh projects. Whiptail targets a 2027 start; Hammerhead is anticipated in 2029.

The sequencing is tight. With Uaru in late 2026, Whiptail in 2027, Hammerhead in 2029 and Longtail in 2030, Exxon is running four start-ups in five years on a single block. Execution risk compounds at that pace, and the company has said nothing yet about project nine.

What did the contractor side already show?

One early marker predates the FID. In April 2026, Saipem received a limited notice to proceed (LNTP) from ExxonMobil Guyana, valued at around $150m (€127.91m), tied to Longtail. An LNTP allows early engineering and procurement before full contract award — a hedge, not a commitment to the full scope.

What the company said

ExxonMobil upstream company president Dan Ammann said: "Guyana is home to one of the world's most prolific energy developments, and Longtail represents the next phase in realising the full potential of its resources."

He added: "By developing these gas and condensate resources, we're unlocking new value for Guyana while delivering advantaged energy to meet growing global demand."

Standard CEO-grade language. Note what is absent: no reserve figures for Longtail, no gas sales agreements, no named FPSO contractor for the main award. The $12.5bn covers the sanctioned offshore scope; the gasmonetization upside is unpriced.

In plain words: Exxon has committed real money to Guyana's gas, but the shoreward market for that gas still has no buyer, no pipe and no date.