Diesel is no longer the cheap fuel

This is not a slow drift that finally crossed a line. Twenty-one of the reversals are less than two years old, and several happened in the last few months. Portugal crossed over in July 2026, with diesel now 0.016 euros a litre above petrol after two decades of sitting well below it.

Five countries have not crossed: Germany, Denmark, Greece, Malta and the Netherlands. In Germany the gap is now so small that it is effectively gone.

Belgium has the widest gap in the Union, with diesel 0.323 euros a litre above petrol. Denmark has the widest gap the other way, and is one of the few places where the old rule still holds.

The obvious explanation is that governments took away diesel's tax break. They did not. Diesel still carries the lower excise in every single one of the 27 countries, exactly as it did twenty years ago.

Here is the part that surprises people. Back in 2005, before a cent of tax was added, diesel was already the more expensive product in almost every country in this list. It only reached the forecourt cheaper because it was taxed more lightly. The discount was never in the fuel. It was in the law.

Since then the raw product has grown dearer relative to petrol, year after year, until the gap outgrew the tax break that used to hide it. The tax advantage is still there. It simply is not big enough any more.

The bulletin records prices, not reasons. It shows that untaxed diesel became relatively dearer across the whole Union, which rules out any single national decision as the cause. It does not tell us why, and this page will not pretend otherwise.

It is also a national weekly average. Your town can sit either side of it, and two stations on the same road can disagree by more than any of the gaps on this chart.

If you drive a diesel car, the habit worth dropping is the assumption. For most of the last twenty years you could pull in anywhere and know your fuel was the cheaper one on the sign. That is no longer true in most of Europe, and in several countries it stopped being true this year.

This does not mean a diesel car is now the wrong car. A diesel engine still burns less per hundred kilometres, and that arithmetic can outweigh a few cents a litre. What changed is that the per-litre part of the advantage, the part you could see on the forecourt, has gone.

Which puts the weight back on the only thing you still control: which station you stop at. Fillz shows what each pump near you charges for your fuel, and counts the detour before telling you the cheaper one is worth it.

Is diesel still taxed less than petrol?

Yes, in all 27 countries. Averaged across the Union, tax is about 47% of the petrol price and about 40% of the diesel price. We broke that down country by country in how much of your fuel price is tax.

Then why is diesel dearer at the pump?

Because the fuel itself costs more. Before tax, diesel has been the more expensive product for the whole period covered here. The tax break used to be larger than that difference, and now it is not.

Should I sell my diesel car?

Nothing here answers that. This is one line item, the price per litre, and a car is decided by consumption, purchase price, servicing, resale and the rules of the city you park in. What this page does is remove one assumption from that calculation.

Where do these numbers come from?

From the European Commission, which has published the price of both fuels in every member state, every week, since 2005. The comparison uses the same country, the same week and the same measure throughout.