For Saudi Arabia’s absolute monarchy, climate action represents a combined threat and opportunity in retaining the oil rents that underpin domestic political institutions and the kingdom’s international influence. Saudi Aramco, the largest source of greenhouse gas-emitting fossil fuel among all firms worldwide, is exposed to numerous risks around continued use of fossil fuels. However, Aramco is also the producer with the world’s lowest cost basis and lowest intensity of greenhouse gas emissions per barrel produced. These attributes suggest that oil from the kingdom should retain a prominent role in oil markets, particularly under climate constraints. While Saudi Aramco’s April 2019 bond prospectus outlines steps the company is taking to ensure that it continues marketing oil far into the future, this paper argues that Aramco’s quest to remain the “last man standing” in global oil depends not just on its substantial cost advantages. Declining social acceptance of fossil fuel combustion suggests that Aramco’s pursuit of carbon competitiveness will assume growing importance.