
Temporary end of Argentina’s retenciones drives pressure in Chicago
- Bullish
- Firm global consumption;
- USDA projects lower global ending stocks for 2025/26;
- Stronger exports in the US;
- Slow Brazilian commercialization and firm domestic demand.
- Bearish
- Wrap-up of Brazil’s safrinha corn harvest;
- Record crop in the US;
- End of Argentina’s retenciones, making the global market more competitive.
Weekly summary | Corn futures on the Chicago Board ended last week sharply lower, trading at US¢422/bu (-0,5%). The market mainly reflected a one-off boost to Argentine corn competitiveness following the temporary end of the retenciones (export taxes). In addition, attention is on the quarterly stocks report to be published tomorrow. The market will watch how the USDA handles the results presented in that release in its September estimates, with possible adjustments to 2024/25 production. Moreover, yields for the 2025/26 crop remain a major question mark, but many analysts expect them to be revised lower in upcoming S&D reports.
Intraday (15 min) Dec/25 contract – CBOT

Source: CBOT. Prepared by StoneX.
Argentina | Last Monday, the Argentine government temporarily suspended export taxes on grains and other agricultural products. The measure was slated to run through October 31 but lasted less than 72 hours, as a US$7 billion inflow target was quickly reached.
The temporary end of these taxes—commonly called retenciones—put heavy pressure on the grains complex at the CBOT. Soybeans were the main loser, as expectations that China would eventually need US beans this year were dented. The Asian country has avoided US-origin soybeans amid the trade war, but there had been hope it would need to turn to the US for origination before Brazil’s harvest early next year—now seemingly less likely, though not ruled out.
Corn was also affected, though to a lesser extent. US corn, with or without retenciones, remains broadly competitive internationally; thus, the impacts were less pronounced for CBOT corn. Moreover, China—the player avoiding US product—is less active in the corn import market. Even so, nearly 1 million tonnes of the cereal were sold by Argentina in that period, which is a meaningful amount.
The Argentine peso is not out of the woods. Even with the US$7 bn inflow from the temporary end of the retenciones and with the US Treasury Secretary, Scott Bessant, signaling willingness to inject additional billions into the country, uncertainties remain high. Argentina faces legislative elections in October, which will shape international confidence in the economy and could generate even greater volatility.
Intraday (15 min) Sep/25 contract – B3

Source: B3. Prepared by StoneX.
Brazil | B3 futures fell again, with the Nov/25 contract closing at R$ 66.20/bag (-0.6%). The dollar trended more steadily over the week, as the market awaited with great expectation the virtual meeting between President Lula of Brazil and President Trump of the US, expected to take place this week. The expectation is that the leaders will find a path to consensus on tariffs, which would be quite positive for the Brazilian currency.
Brazilian basis eased slightly during the week, but Brazilian corn remains expensive in the export market. September shipment pace is in line with last year and may end the month slightly higher—still short of potential given this year’s large crop.
Planting of the summer crop is proceeding normally, reaching 25.3% last Friday. In addition, soybean planting is also on a normal pace, reducing concern over next year’s safrinha planting window.
Futures contracts traded on the CBOT (US¢/bu)


Source: CME. Prepared by StoneX.
Futures contracts traded on B3 (R$/bag)


Source: B3. Prepared by StoneX.
Spot prices in Brazil (R$/bag)


Source: StoneX.
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