Rising Sulfur Costs Could Reshape Global Food Prices

The machinery that feeds the world runs on sulfur, and right now, sulfur is getting expensive. As oil production declines globally, the sulfur that emerges as a byproduct of refining crude is becoming scarcer. That scarcity is pushing prices higher, and the ripple effect moves directly into the fertilizer industry—the backbone of modern agriculture. When fertilizer costs rise, farmers face harder choices about how much to apply to their fields. Those choices, multiplied across millions of acres, eventually show up in grocery stores.

Sulfur's role in fertilizer production is not incidental. The element is a key ingredient in many of the compounds that farmers spread on soil to boost crop yields. Without adequate sulfur, the nitrogen and phosphorus in fertilizer cannot be fully utilized by plants. This means that as sulfur becomes harder to source and more expensive to buy, the entire fertilizer supply chain feels the pressure. Producers must pay more for raw materials, and those costs get passed along to agricultural suppliers, then to farmers, then to consumers.

The connection between oil and sulfur is straightforward but often invisible. When refineries process crude oil, sulfur comes out as a waste stream. For decades, this byproduct was abundant and cheap—almost a gift to the fertilizer industry. But as oil companies worldwide pump less crude, the volume of sulfur available as a refining byproduct shrinks proportionally. There is no easy substitute. Sulfur cannot be synthesized at scale in the way some other industrial chemicals can. The world must either extract it from the ground through mining, which is expensive and environmentally costly, or rely on the refining byproduct, which is now dwindling.

Fertilizer prices have already begun to climb in response. Agricultural economists are watching closely, because fertilizer costs are one of the largest variable expenses for farmers. When those costs spike, farmers often respond by reducing application rates—using less fertilizer per acre to preserve margins. The short-term effect is lower input costs for individual operations. The long-term effect is lower yields. Smaller harvests mean tighter global food supplies, which typically translates to higher prices at the consumer level.

The timing compounds the problem. Global food prices have been volatile in recent years, driven by weather disruptions, supply chain friction, and geopolitical tensions. Adding a structural constraint on fertilizer availability—one rooted in declining oil production—introduces a new source of pressure that is harder to reverse quickly. Oil production does not snap back overnight. Sulfur supplies will remain constrained for as long as refineries process less crude. This is not a temporary shortage that markets can easily arbitrage away.

Farmers in regions dependent on imported fertilizer face the sharpest pressure. Countries without domestic sulfur mining capacity or oil refining infrastructure must buy on the global market at whatever price prevails. Developing nations with tight agricultural budgets may find themselves unable to afford the fertilizer their crops need, potentially widening the gap between food-secure and food-insecure regions. Wealthier agricultural producers can absorb higher input costs more easily, but the poorest cannot.

The question now is whether the fertilizer industry will adapt fast enough to prevent widespread disruption. Some producers are exploring alternative sulfur sources or reformulating products to require less of it. Others are investing in sulfur recovery technologies that could extract the element from sources beyond oil refining. But these transitions take time and capital. In the near term, the market is simply adjusting to a new reality: sulfur is no longer abundant, and the cost of feeding the world is rising as a result.