Portugal Fuel Prices: Diesel & Gasoline Update – March 23-29, 2026

Portugal’s Ministry of Finance announced this week a forthcoming reduction in fuel prices, effective next week, with a decrease of 3.2 cents per liter on diesel and 1.7 cents per liter on gasoline. The adjustments come as part of a continuing policy of modulating the Internal Petroleum Tax (ISP), triggered when price increases exceed 10 cents.

Despite the government intervention, the final price at the pump remains determined by individual brands and gas stations, reflecting a free-market approach to fuel pricing in Portugal. The announced ISP adjustments are intended as indicative values, assisting consumers in deciding whether to refuel immediately or wait until Monday for the changes to take effect.

Currently, diesel prices are expected to rise by a net 12.8 cents per liter, factoring in the 16-cent increase and the 3.2-cent ISP reduction. Gasoline prices are projected to increase by 7.3 cents per liter, accounting for the 9-cent rise and the 1.7-cent ISP decrease. These figures follow a series of prior adjustments, with the ISP having been previously “unfrozen” after a period of stability.

Based on these projections, the average price per liter of fuel is anticipated to be €2.055 for diesel and €1.925 for gasoline next week. For comparison, the average price of diesel was €1.659 on February 1, 2025, and gasoline was €1.764 on the same date.

Consumers seeking the lowest prices are advised to consult resources that identify the cheapest gas stations in their vicinity. The Ministry of Finance did not specify a timeframe for the continuation of these adjustments, leaving the future of fuel pricing subject to market fluctuations and further government intervention.