The Portuguese Government now has 180 days to finalize a major overhaul of how vehicle owners pay their annual road tax, a shift that will end the current system tied to individual registration anniversaries and replace it with a unified national calendar starting in 2027.
Why This Matters:
• Fixed deadlines replace registration dates: All vehicle owners will pay on the same dates each year, regardless of when they bought their car.
• Transition year in 2027: A special one-time calendar applies next year to prevent double-billing conflicts.
• Installment options expand: From 2028, taxes above €100 can be spread across multiple months.
• No tax increase: The reform changes when you pay, not how much you owe.
The Legislative Timeline
The Portuguese Assembly of the Republic approved the legislative authorization on April 17, 2026, with support from most parliamentary groups. Chega, the Communist Party (PCP), Left Bloc (BE), and PAN abstained. President Marcelo Rebelo de Sousa promulgated the law on May 26, and it was published in the Diário da República this week. The Cabinet must now draft the technical regulations within six months to implement the new Imposto Único de Circulação (IUC) payment structure.
Currently, Portuguese vehicle owners pay their IUC in the month their car was first registered—a system that has been in place for years but generates administrative friction. The government argued that consolidating payment dates would simplify tax administration and help vehicle owners better manage their obligations across multiple vehicles.
The reform, part of the broader "Agenda for Tax Simplification," seeks to harmonize vehicle taxation with the fixed-date model already used for the Imposto Municipal sobre Imóveis (IMI), Portugal's municipal property tax.
What Changes in 2027
The transition year introduces a temporary calendar designed to prevent taxpayers from being hit with both their 2026 IUC (due on their registration anniversary) and their 2027 IUC within weeks of each other.
For IUC bills up to €500, the entire amount will be due in a single payment in October 2027. This bracket covers the majority of passenger vehicles in categories A, B, C, D, and E—motorcycles, standard cars, light commercial vehicles, buses, and heavy trucks under certain weight limits.
For IUC bills exceeding €500, owners must pay in two installments: July and October 2027. Taxpayers retain the option to settle the full amount in July if they prefer to avoid the second deadline.
Importantly, the 2027 rules include a cancellation provision: if you deregister your vehicle (sell it, export it, or scrap it) before the anniversary date of its original registration, you can request cancellation of that year's IUC liability. This clause addresses a common concern under the old system, where owners who sold cars early in the year still owed the full annual tax.
The Permanent System from 2028 Onward
Starting January 1, 2028, the IUC switches to a calendar-year basis with fixed national deadlines. The number of installments depends on the total annual tax owed per taxpayer, not per vehicle.
IUC up to €100: Pay in full by the end of April. This tier typically includes older, low-emission vehicles, motorcycles under 250cc, and some hybrid models.
IUC between €101 and €500: Split into two installments in April and October. This range covers most family sedans, compact SUVs, and mid-range diesels registered before stricter emissions rules took effect.
IUC above €500: Divided into three installments in April, July, and October. High-displacement engines, luxury vehicles, and older diesel models with elevated CO₂ ratings fall into this category.
The legislation specifies that missing any installment triggers immediate acceleration of the remaining balance, meaning the AT can demand full payment and levy penalties if you default on one portion. The tax authority must also aggregate all vehicles registered to the same taxpayer when determining the total annual IUC, which could push multi-car households into higher installment brackets.
Impact on Residents and Expats
For Portuguese families, the change simplifies budgeting by providing clear, predictable payment dates. Instead of tracking multiple registration dates—particularly important for households with a car, a motorcycle, and perhaps a small commercial van—everyone will know to plan for April, July, and October deadlines.
Foreign residents and expats who own Portugal-registered vehicles should note that the reform does not alter IUC rates or eligibility. Fully electric vehicles remain exempt from IUC under current law, a benefit that continues regardless of the new calendar. Plug-in hybrids and mild hybrids, however, still pay based on their CO₂ emissions and engine displacement.
For those who lease or finance vehicles, responsibility for IUC payment typically remains with the registered owner (often the leasing company), but confirm your contract terms. Some lease agreements pass the IUC obligation to the lessee and may adjust monthly payments to reflect the new installment schedule.
If you plan to import a used car into Portugal, the first-year IUC exemption applies proportionally based on the number of complete months elapsed from January 1 to your vehicle's registration date. Under the 2028 rules, registering a vehicle in May would mean an exemption proportional to the months from January through May, with payment obligations beginning thereafter, settled in the applicable installments.
Why the Government Chose Fixed Dates
Portuguese officials cited the IMI precedent as supporting evidence. The municipal property tax has used fixed April and September deadlines for decades. By consolidating IUC payment dates to a fixed national calendar, the government aims to create a similar predictable system that is easier for taxpayers and the tax authority to manage.
The government also noted that the change aligns with ongoing efforts to simplify tax administration across Europe, where various countries organize vehicle taxation on fixed calendars to improve compliance and reduce administrative burden.
Addressing Policy Questions
Critics from the Left Bloc and PAN abstained from the vote, arguing that while the calendar reform is administratively sound, it does not address underlying concerns about the equity of IUC rates for older vehicles. Pre-2007 cars, taxed on engine displacement rather than emissions, can face disproportionately high rates compared to some newer models. The government countered that rate reform is a separate policy matter and that addressing it within this reform would delay the simplification indefinitely.
What Stays the Same in 2026
For the remainder of this year, nothing changes. Vehicle owners must still pay their IUC in the month their car was originally registered. The AT will send payment notices approximately 30 days in advance, as it does now, and the usual grace periods and electronic payment options apply.
If your IUC due date falls in the second half of 2026, keep in mind that your next payment will follow the new 2027 transitional calendar, potentially shifting your obligation forward or backward by several months. The AT is expected to issue detailed guidance and individualized notices to affected taxpayers, and proactive checking via the Finanças Portal is advisable, especially for multi-vehicle households.
Fully electric vehicle owners can continue to disregard IUC correspondence entirely, as their exemption persists under all iterations of the reform. Hydrogen fuel-cell vehicles also enjoy this waiver, though their market share in Portugal remains negligible.
Administrative Preparations and Outstanding Questions
The 180-day deadline means the Cabinet must publish implementing regulations by early December 2026. These rules will clarify how the AT's systems will aggregate vehicles per taxpayer, how installment notices will be generated, and what happens if ownership changes mid-year under the new calendar framework.
The government will also need to address implementation questions regarding classic and historic vehicles, which qualify for reduced IUC rates under separate legislation, and how these vehicles will be integrated into the new payment schedule.
Planning Ahead
Vehicle owners should mark calendars now for the 2027 transition deadlines—July and October for high-value IUC, October only for most others—and budget accordingly. Those accustomed to spreading payments across the year under the old registration-date system may find the concentrated schedule tighter on cash flow, though the installment options from 2028 onward should ease that pressure.
For anyone considering vehicle purchases in the coming months, the new system means your acquisition date will matter less for tax timing. Buying in January versus December will no longer shift your annual IUC obligation by nearly a full year.
Finally, keep an eye on the AT's website and your tax mailbox in the final quarter of 2026, when detailed 2027 notices are expected. Early checks of the self-service portal are advisable to understand how the new rules will affect your specific situation.
