Fuel prices to rise again next week
Fuel prices in Portugal are set to increase again on Monday, with diesel expected to rise by up to nine cents per litre and petrol by up to four cents. Despite the government applying a new discount to the tax on petroleum products (Imposto sobre os Produtos Petrolíferos or ISP), international market volatility continues to drive costs higher. This marks the fifth consecutive week of rising prices linked to the ongoing conflict in the Middle East.
The ISP (Imposto sobre Produtos Petrolíferos e Energéticos) is Portugal's excise tax on petroleum and energy products, charged as a fixed amount per liter on petrol, diesel, and other fuels. It is one of the main components of fuel prices at the pump, alongside VAT and the carbon tax (Taxa de Carbono).
The government can adjust ISP rates — temporarily or permanently — to influence fuel prices. Rate cuts are a common policy tool to ease cost-of-living pressures on drivers and transport businesses, though they also reduce government revenue.
For consumers, the ISP is significant because even small changes in the per-liter rate translate into noticeable differences at the pump, particularly for diesel users and commercial transport operators.
