Most large oil and gas companies will enter 2027 with gearing below 20%, according to Wood Mackenzie's Corporate Strategic Planner Oil & Gas 2027, and that financial headroom sets the platform for a 5% rise in investment, a fresh wave of M&A, and the resource renewal companies need to sustain production into the 2030s.

The analysis, published by Senior Editor Elizabeth Corner at Oilfield Technology, attributes the accelerated deleveraging to surging prices and margins in 2026. The question now is what companies do with the balance-sheet capacity.

How steep is the production decline?

Excluding Middle Eastern NOCs, production across Wood Mackenzie's five peer groups falls 31%, or 18 million boe/d, between 2030 and 2040. That structural decline drives the 2027 push for M&A and upstream business development.

"Balance sheets are in good shape. But a 31% production decline between 2030 and 2040 means companies will have to manage rising tension between capital discipline and upstream portfolio renewal in 2027. That dilemma is the defining feature of the 2027 planning cycle," said Tom Ellacott, Senior Vice President, Corporate Research, Wood Mackenzie.

Will capital discipline hold?

Wood Mackenzie expects it to hold, even at Brent prices above its US$73/bbl base case. The consultancy forecasts for 2027:

• Reinvestment rates averaging 50% of operating cash flow
• Distributions of 43%, split 32% dividends and 11% buybacks
• A post-investment and post-dividend breakeven of US$55/bbl on average

Operating cash flow in 2027 should remain 14% above 2025 levels at base-case pricing. At US$90/bbl, cash flow rises a further 18%, or US$104 billion. A fall to US$50/bbl would cut operating cash flow by 24%, or US$138 billion, with US Majors, Large Cap US, and Large Cap International peer groups facing declines of 28% to 29%. Companies will need action plans for both scenarios.

Where does the upstream capital go?

Upstream's share of total capital is up eight percentage points since 2021, as Power and Renewables spend — which peaked in 2024 — continues to fall. Two thirds of upstream capital for the peer group flows to the Middle East and the Americas, where tight oil, deepwater, and LNG dominate the growth themes.

M&A activity will depend on whether volatility falls enough for buyers and sellers to align on price, Wood Mackenzie said. Rising equity valuations give some companies a financing advantage in equity-led deals.

"Capital allocation constraints and the pressure to rebuild upstream portfolios for the next decade are already triggering more NOC-IOC partnerships and strategic ventures," said Neivan Boroujerdi, Head of Corporate NOC Analysis at Wood Mackenzie. "Geographic diversification, particularly toward the Americas, will be front of mind as companies respond to shifting geopolitics in 2027."

What changes downstream?

Downstream is diverging. Refining closures continue in Europe and California, but 2026 exposed how thin the system has become, making the pace of exits a more deliberate question. In chemicals, near-term overcapacity is separating those committing through the trough from those exiting entirely, with feedstock advantage as the dividing line.

Fundamentals have not changed, according to Wood Mackenzie, but the 2027 question is no longer just how fast to shrink — it is how much flexibility is worth retaining while the system stays tight.

What happens to low-carbon spending?

NOCs' low carbon spend is now double that of the Euro Majors following the latter's strategic recalibration. Most large IOC and NOC low carbon budgets are converging on 5% to 10% of total spend, against prior estimates of up to 50% from some Euro Majors at peak ESG guidance levels.

Some players will keep building. TotalEnergies remains focused on integrated power, while Eni leverages its strategic ventures Plenitude and EniLive.

The watch item: whether volatility falls enough in 2027 for M&A buyers and sellers to align on price — and whether the 50% reinvestment rate proves enough against an 18 million boe/d decline curve after 2030.