Finanças Reweights the ISP Combustível Discount With a +0.77-Cent Diesel Top-Up and a –0.02-Cent Gasolina Trim From 9 June — Pump-Week Extraordinary Rebate Holds at €51.45 and €41.97 per 1,000 Litres

The Ministério das Finanças (Ministry of Finance) reweighted Portugal's extraordinary Imposto sobre Produtos Petrolíferos e Energéticos (Tax on Petroleum and Energy Products, ISP) rebate on 5 June 2026, raising the discount on diesel by 0.765 cents per litre and trimming the gasoline rebate by 0.021 cents. The new portaria, published in the Diário da República (Official Gazette), takes effect at the 9 June pump-week roll-over and leaves the cumulative ISP support at €51.45 per 1,000 litres for diesel and €41.97 per 1,000 litres for gasoline — the headline rebates that have anchored the relief mechanism since the 13 March portaria first wrote it into force.

The retune follows the Direção-Geral de Energia e Geologia (Directorate-General for Energy and Geology, DGEG) weekly read on the international product-market: diesel quotations point to a 4-cent climb at the pump in the coming seven days, while gasoline is expected to ease by roughly 1 cent. Finanças sets the ISP rebalance to absorb part of the diesel rise — leaving consumers with a net climb closer to 3.2 cents per litre — and gives back a fraction of the gasoline subsidy as the pump price moves the other way. The new pump-week reference prices the DGEG circulates for the 9-15 June window land at €1.928 per litre for simples 95-octane gasoline and €1.905 per litre for simples diesel.

How the trigger mechanism works

The extraordinary ISP discount sits on top of the base ISP rate set in the Código dos Impostos Especiais de Consumo (Excise Code, CIEC). The mechanism, introduced in March 2026 as a response to the price spike following geopolitical pressure on Middle East crude, recalibrates whenever DGEG's weekly product-market scan shows pump prices diverging by more than 10 cents from the reference week of 2-6 March 2026. The portaria publishes the new ISP rates each Thursday or Friday with effect at the Monday roll-over; haulier-grade gasóleo profissional sits on a parallel three-month support track ratified 1 April through 30 June.

What the new rates mean at the pump

For a private car with a 50-litre diesel tank, the 0.765-cent top-up lifts the per-tank ISP saving to €2.57 versus a no-discount baseline. The 0.021-cent gasoline trim translates to a €0.01 reduction per 50-litre fill on the rebate side — effectively a rounding adjustment against the expected 1-cent pump-price decline. Hauliers reclaiming gasóleo profissional through Autoridade Tributária (Tax Authority, AT) channels see no change in the parallel professional-diesel rebate, which remains pegged to the bracket negotiated with the freight-transport associations through end-June.

The fiscal envelope

Finanças has not updated the 2026 ISP-relief envelope in the latest portaria, but the cumulative cost of the extraordinary discount since 13 March was running at roughly €11 million per week against the Q1 2026 traffic baseline — the figure the budget office uses in the State Budget execution report. With diesel volumes structurally larger than gasoline in the Portuguese fleet, the diesel-side reweighting is the binding line in the envelope: each cent of diesel rebate represents around €4.5 million per month of foregone ISP receipts, against €1.6 million on gasoline. The June recalibration tilts that ratio further toward diesel, in line with the freight-cost passthrough that drives food and consumer-goods inflation in INE's monthly CPI release.

Sources: PÚBLICO (5 June 2026), TSF (5 June 2026), ECO (5 June 2026), Jornal Económico (5 June 2026), portugal.gov.pt (Ministry of Finance communiqué), Diário da República.