Last updated: 6 October 2026, after Budget 2027.
Petrol in Ireland averaged about €1.97 a litre and diesel about €2.12 a litre in late September 2026. Both are held down by a temporary excise cut of 27c a litre on petrol and 32c on diesel. Budget 2027 keeps that cut until 28 February 2027, then brings the full tax back in four steps by 30 June 2027. Carbon tax on petrol and diesel also goes up twice in 2027.
If oil prices stay where they are, that puts petrol at about €2.28 a litre and diesel at about €2.49 a litre by the end of 2027.
⚡ Quick Summary
🌿 Petrol now: about €1.97 a litre (national average, 28 September 2026).
🌿 Diesel now: about €2.12 a litre (national average, 28 September 2026).
🌿 Excise cut: 27c a litre off petrol and 32c off diesel, at this level since April 2026, extended to 28 February 2027.
🌿 Excise comes back: in four steps after 28 February 2027, fully back by 30 June 2027.
🌿 Carbon tax: €71 per tonne now. Goes up on 1 May 2027 and again on 13 October 2027.
🌿 Biggest jump: the excise cut ending adds about 27c a litre to petrol and 32c to diesel at the pump.
⛽ Work Out Your 2027 Fuel Costs
Put in the price you pay now, your tank size and how often you fill up. The calculator shows what a litre and a fill could cost once the excise cut ends and carbon tax rises in 2027.
Indicative estimates only. Assumes the oil price itself stays the same, which it will not. Carbon tax changes include 23% VAT. The excise cut figures are pump price cuts that already include VAT. Excise: the temporary cut of 27c per litre on petrol and 32c on diesel ends after 28 February 2027 and is fully back by 30 June 2027, in four steps whose exact dates and amounts are not yet published. Carbon tax: the rise on 1 May 2027 is worked out at €71 to €78.50 per tonne of CO₂. The 13 October 2027 rise assumes a further €7.50 per tonne, the usual yearly step; the exact rate is not yet published.
📅 What Changes and When
Budget 2027, announced on 6 October 2026, set out these dates for petrol and diesel:
🌿 Now to 28 February 2027: the excise cut stays. Minister for Finance Simon Harris said there will be no tax rise at the pump this winter.
🌿 March to June 2027: the excise cut is taken back in four steps. The Government has not yet published the date or size of each step.
🌿 1 May 2027: carbon tax on petrol and diesel goes up from €71 per tonne of CO₂. This is the rise that was due in October 2026 and was paused.
🌿 30 June 2027: excise fully back to its normal rate.
🌿 13 October 2027: carbon tax on petrol and diesel goes up again. The Department of Finance says this puts these fuels back on the path to €100 per tonne by 2030.
Other fuel measures from the same Budget:
🌿 NORA levy: the lower rate stays until 31 December 2026.
🌿 Diesel Rebate Scheme: the enhanced scheme for hauliers runs to the end of December 2026.
🌿 Green (marked) diesel: carbon tax goes from €63.50 to €78.50 per tonne on 1 May 2027.
💶 How Much Each Change Adds per Litre
The excise cut ending is by far the biggest change. The carbon tax rises add only a couple of cent each.
🔹 Petrol
🌿 Excise cut ending: about 27c a litre at the pump
🌿 Each carbon tax rise of €7.50 per tonne: about 2c a litre
🌿 Total by the end of 2027: about 31c a litre, or about €16 more on a 50-litre fill
🔹 Diesel
🌿 Excise cut ending: about 32c a litre at the pump
🌿 Each carbon tax rise of €7.50 per tonne: about 2.5c a litre
🌿 Total by the end of 2027: about 37c a litre, or about €18.50 more on a 50-litre fill
These figures assume the price of oil itself does not change. In 2026 the Middle East conflict pushed oil prices up sharply, and they can move by more than the tax changes in either direction.
🧾 What Is in the Price of a Litre
Using the late September 2026 average petrol price of about €1.97 a litre, roughly:
🌿 The fuel itself, delivery and retailer margin: about €1.10
🌿 Excise (Mineral Oil Tax, including carbon tax): about 50c, with the 27c cut applied
🌿 VAT at 23%: about 37c
Carbon tax is part of the excise figure. At €71 per tonne it is about 16c a litre on petrol and 19c on diesel, before VAT. Our carbon tax guide explains the rates on every fuel.
🚗 Ways to Spend Less on Fuel in 2027
🌿 Fill up before the excise steps: each of the four steps between March and June 2027 pushes the price up. Filling the tank the day before a step saves a few euro each time.
🌿 Shop around: prices can differ between stations in the same area, so check a few before filling up.
🌿 Drive gently: smooth driving, correct tyre pressure and less weight in the car all cut fuel use.
🌿 Think about electric: an electric car pays no excise or carbon tax on fuel. See our guides to electric cars in Ireland, the EV grant and VRT relief (now extended to the end of 2028), and the cheapest electric cars.
⚠️ Common Mistakes
🌿 Blaming the carbon tax for the 2027 jump: the carbon tax rises add about 2c a litre each. The excise cut ending adds 27c to 32c.
🌿 Thinking prices rise in one go: the excise comes back in four steps between March and June 2027, not all at once.
🌿 Thinking diesel and petrol rise by the same amount: diesel had the bigger cut (32c against 27c), so it goes up more.
🌿 Mixing up the heating oil cut with petrol: Budget 2027 cut carbon tax on home heating oil and gas, not on petrol or diesel.
❓ Frequently Asked Questions
🔹 When does the fuel excise cut end in Ireland?
The cut of 27c a litre on petrol and 32c on diesel stays until 28 February 2027. After that it is taken back in four steps, and the full excise is back by 30 June 2027.
🔹 How much will petrol cost in 2027?
If oil prices stay at late September 2026 levels, petrol would be about €2.26 a litre by July 2027 and about €2.28 by the end of 2027. Diesel would be about €2.47 by July and about €2.49 by the end of 2027. Oil price changes could push these up or down.
🔹 Did Budget 2027 increase the carbon tax on petrol and diesel?
Not straight away. The rise due in October 2026 was paused. Instead, carbon tax on petrol and diesel goes up twice in 2027, on 1 May and 13 October.
🔹 How much carbon tax is in a litre of petrol?
About 16c a litre on petrol and 19c on diesel at €71 per tonne, before VAT. With 23% VAT, about 20c and 23c.
🔹 Will the government extend the excise cut again?
The cut has been extended several times in 2026. Budget 2027 set a plan to bring it back in full by 30 June 2027, but the Government could change this if oil prices rise sharply.
🔹 Is diesel always dearer than petrol in Ireland?
Not always, but it has been through 2026. Diesel was about 15c a litre dearer than petrol in late September 2026, and it has the bigger excise cut to lose in 2027.
Climate Jargon Buster is an independent resource giving plain-English information on climate, energy and transport costs for an Irish audience. Average prices are national averages for 28 September 2026 based on EU Weekly Oil Bulletin data. Tax changes are based on Budget 2027 announcements of 6 October 2026. Price estimates assume oil prices do not change and are not forecasts. For official tax rates, visit revenue.ie.