Agricultural (green) diesel in construction machines and aerial platforms: when it is allowed and the fines (2026)

In short: marked diesel (Portugal’s “gasóleo agrícola” or “green diesel”) costs about €0.35 less per litre, but may only be used in registered farm, forestry and aquaculture machines, irrigation engines, fixed engines and a few other cases. No aerial work platform is on the list, and telehandlers, excavators, forklifts and loaders may only use it while working on a farm or forestry operation that holds the card. On a construction site, in a factory or in a rental yard it is always illegal. The fine ranges from €250 to €165,000 per machine, plus the unpaid duty and loss of the card.

This guide explains what Portuguese law says in 2026, which construction machines are in and out, how marked diesel is bought, and what happens to those who are caught. It is not legal advice: if in doubt, check with your regional CCDR, DGADR or customs.

What marked diesel is

It is the same diesel sold at the pump, with a blue dye and a chemical marker (ACCUTRACE PLUS, mandatory since January 2024) that give it a greenish colour and let a laboratory detect it even when mixed with normal diesel. In exchange, it carries far less tax: €21 of fuel duty per 1,000 litres instead of about €259, and 13% VAT instead of 23%.

For a machine burning 5,000 litres a year, the difference is around €1,750 a year at October 2026 prices. That is why the temptation exists, and why enforcement is strict.

In 2026 there is also an extraordinary support of 10 cents per litre for cardholders in farming, forestry, fishing and aquaculture, paid by IFAP in weeks when the average price is more than 10 cents above March 2026 (Decree-Law 80-A/2026, extended to 31 December by Decree-Law 200/2026).

When it is allowed

Article 93 of the Excise Duties Code (CIEC) says marked diesel “may only be consumed by”:

1. Stationary engines used for irrigation.
2. Certain vessels (fishing, coastal navigation and others set out in the law).
3. Equipment used in farming, forestry, aquaculture and arte-xávega beach-seine fishing, approved by regulation (currently Portaria 50/2020).
4. Railway vehicles.
5. Fixed engines, meaning engines that produce energy and are installed on immovable platforms.
6. Self-contained refrigeration units on trucks carrying perishable goods with an ATP certificate.

The list is closed. If the machine or the use is not on it, marked diesel is illegal, however cheap it is and however “agricultural” the machine looks. One rule many people forget: being on the list is not enough, the machine must be working in the declared activity. The regulation requires the fuel to be used “exclusively in the activity and the equipment authorised for that purpose”.

Which construction machines and platforms may use it

Aerial work platforms: never. Scissors, articulating and telescopic booms, spider lifts and truck-mounted platforms are not on the regulation’s list, whether on a site or on a farm. The only arguable case is self-propelled fruit harvesters (which the regulation accepts), but a generic aerial platform used for pruning or picking is not a harvester. If you think a machine qualifies, get written confirmation from the CCDR before filling it.

Telehandlers, excavators, forklifts and loaders: only in farming and forestry. These machines are on the list, but only when registered on the manifest of a farmer, forestry body or agricultural contractor and working in that activity. The same Manitou or JLG telehandler that stacks straw bales on a farm with a card may use green diesel; if it unloads pallets of bricks on a building site the next day, it must run on road diesel.

Site generators, compressors and lighting towers: no. The law only accepts “fixed engines”: engines producing energy, installed on an immovable base, with prior recognition by customs. A towable or skid-mounted generator, a compressor or a lighting tower moving from site to site does not qualify.

Dumpers, cranes, trucks and concrete mixers: no. They are on no list.

Practical cases that cause confusion

A farmer with a tractor-backhoe doing outside work. They may use marked diesel for farming or forestry work on other people’s land if registered as an agricultural contractor (activity codes 01610, 01620 or 02400) and able to justify consumption with invoices for those services. Digging a trench for a house’s drainage, clearing a plot for building or working on a road is not farming: that needs road diesel.

A contractor who also owns farmland. They can register the machines used on the farm, but a machine that alternates between farm and site creates a practical problem: the tank keeps green diesel and lab tests detect it. In practice, either the machine stays on the farm or it always runs on road diesel.

A rental company hiring a telehandler to a farmer. The farmer may add the rented machine to their manifest with the rental contract or a declaration of transfer (Portaria 50/2020 art. 45) and fill it with marked diesel while it works on the farm. When the rental ends, they should remove it from the manifest straight away. The machine returns to the yard with green diesel in the tank, and the next customer, on a building site, is exposed. There is no official guidance on this; our recommendations for rental companies are below.

A used machine bought from a farmer. The benefit does not pass to the buyer. If the machine has green diesel left in the tank, lines or filters, a test can come back positive. Keep the purchase invoice and drain and clean the fuel system before putting it to work (see also our used aerial platform buying checklist).

New in 2026: quarries and mines

The 2026 State Budget (Law 73-A/2025, article 221) allows extractive-industry companies to use marked diesel “in all unregistered equipment assigned to the activity”: dumpers, loaders, excavators and crushers working inside the quarry or mine. Three limits apply:

• It only covers companies whose business is extraction, and only machines without number plates. A builder digging aggregate for its own site is not covered.
• The rest of the law (CIEC article 93 and Portaria 50/2020) was not changed. As of October 2026 we found no regulation or published procedure explaining how quarries apply for the card.
• Before filling up, confirm with the CCDR, DGADR or the sector association (ASSIMAGRA) that your application has been recognised. Without a card, the fine for buying without a card applies.

How marked diesel is bought (by those entitled to it)

1. Have the right activity. A declared farming, forestry or aquaculture activity under one of the codes in Annex II of Portaria 50/2020, or agricultural or forestry contracting (codes 01610, 01620, 02400), with tax and social security affairs in order.
2. Apply in person. At the regional CCDR (which absorbed the former regional agriculture directorates in 2024) or a partner organisation. There is no online application, and you can apply all year.
3. Submit the machine manifest. Tractors and backhoes with registration document and number plate; other machines with the purchase invoice, rental contract or declaration of transfer. Some CCDRs ask for photos of make, model, year and chassis number.
4. Receive the card. It is issued by DGADR, costs €30 (the first one), is valid for five years and is personal and non-transferable. Lending it leads to suspension.
5. Fill up only in the authorised network. At stations with a “Gasóleo Verde” pump or a mobile terminal on site, using the card and PIN. The invoice must carry the holder’s name and tax number.
6. Respect the allowance. Each machine has an indicative annual volume (table above) and irrigation counts 150 litres per irrigated hectare. You may exceed it, but you will be inspected. Consumption can be checked online on DGADR’s website.
7. Report changes within 5 working days. Sale or transfer of a machine, end of the activity (the card must be returned) or changes in your details.

For fishing boats the card is requested from DGRM. In Madeira no card is needed.

Fines and other consequences

In practice, anyone caught with green diesel in a construction machine faces three things at once: the fine (one per machine with illegal fuel), the duty they avoided and, if they hold a card, loss of the benefit. If the amounts are large and there was intent, it becomes a crime: at October 2026 rates, €15,000 of unpaid duty corresponds to about 60,000 litres.

Companies are liable for offences committed in their name by managers and representatives, and managers are secondarily liable for the company’s fines. A company only escapes liability for an employee’s acts if it proves it took the necessary steps to ensure the law was followed (RGIT articles 7 and 8).

How enforcement works

Enforcement is done by the Tax and Customs Authority (AT) and the GNR’s Tax Action Unit, which is legally tasked with policing marked diesel “in unauthorised vehicles or equipment”. On the spot, inspectors may use a portable detector, but proof comes from the laboratory: they take three sealed samples, two go to the AT lab and the third stays with the machine’s owner for a counter-test. The lab reports the percentage of marked diesel in the mix, so old residue in the tank shows up too.

Three real court cases show what is at stake:

• Telehandler and backhoe (Central Administrative Court South, case 5446/01). The GNR seized a company’s Manitou telehandler with a tank full of green diesel, plus a backhoe. The company was fined and both machines were declared forfeit to the State. The court rejected the appeal and said the machines did not need to be working for an offence to exist. The case predates the current law, but shows that fuel in the tank is enough to start proceedings.
• Used generators, compressor and dumper (Central Administrative Court South, case 07799/14). The GNR found two generators, an Atlas Copco compressor and a Volvo dumper in a yard with 55% to 67% marked diesel. Customs imposed €4,500 (nine €500 fines). The court acquitted because the company proved it had bought the machines second-hand to resell, without batteries and without using them, and that the fuel came from previous owners. The lesson: purchase invoices and proof that the company did not fill the machine matter.
• Shared pump on a farm (Central Administrative Court North, case 00401/20.8BECBR). A company with a card used the same pump for normal and marked diesel and had green diesel in a machine that was not registered. A €2,000 fine, annulled in 2025 only because of a procedural error.

What we recommend to construction and rental companies

There is no official guidance for rental companies. These are the precautions that, in our reading of the law and the cases above, reduce the risk:

• Ban marked diesel in the rental contract, except agricultural rentals with a declaration of transfer, and state that the customer is liable for fines and cleaning.
• Check the fuel colour at delivery and return and record the level. Greenish diesel in a tank is a warning sign.
• Drain the tank and change the filters after an agricultural rental with marked diesel, before the machine goes to a building site, and keep a record.
• Keep road-diesel invoices linked to each machine; they are the best defence if a test is positive because of old residue.
• Train whoever refuels: never fill site machines from a farm tank, or from a neighbour “who has a card”.

What about other countries?

In Spain, gasóleo B (the equivalent of Portugal’s marked diesel) may be used in all engines except vehicles authorised to drive on public roads (other than farm vehicles) and leisure boats. So unregistered construction machines, including aerial platforms, may use it there. A machine that works in Spain on gasóleo B and comes back to Portugal with a full tank is exposed here. In the UK, construction lost its red-diesel entitlement in April 2022 and companies had to flush their tanks.

Legal ways to spend less on fuel

If the goal is to cut fuel costs on a site, marked diesel is not the way. What works:

• Switch to electric or hybrid whenever ground and height allow. An electric scissor lift uses less than €2 of electricity a day; see the guide diesel or electric aerial work platform.
• Don’t oversize: a 16 m articulating boom burns around 5.7 l per engine hour, a 40 m telescopic more than 9 l.
• Switch the engine off instead of idling; on construction machines, idling can reach a third of engine hours.

“Professional diesel” (a partial fuel-duty refund) does not apply either: it is only for licensed goods trucks from 7.5 t and buses, not for machines.