IRS reduction in 2026: Why renting out a room in your primary residence in Portugal is becoming highly profitable

Do you have an unused room in your house or apartment in Portugal? In an economic climate marked by inflation and an unprecedented housing crisis, many hosts are looking for ways to generate extra income. At Roomlala, we know that taking the step of renting out a room in your home can sometimes raise questions, particularly regarding administrative and tax matters. Good news: the Portugal room rental tax system for 2026 has been completely rethought by the government to benefit you considerably. In order to encourage the supply of housing and rooms for long-term stays, the Portuguese state has rolled out an arsenal of highly incentive-based tax measures. Gone are the days when taxes gobbled up the majority of your rental income! Today, renting out a room in your home in Portugal has never been safer, more legal, and, most importantly, more profitable. In this comprehensive article, we break down the latest legislative developments for you. You will discover how to optimise your returns, drastically reduce your income tax (IRS), and secure your process through long-term leases.

Portugal housing law 2026: The new tax landscape for hosts

To understand the opportunity available to you this year, you need to look at the recent Portugal housing law 2026. Faced with a shortage of affordable housing, particularly in cities like Lisbon, Porto, or Faro, the government has enacted Decree-Law no. 97/2026. This new tax package has a clear objective: to discourage short-term tourist rentals in favour of standard residential rentals. At Roomlala, we observe that this transition perfectly matches the expectations of our community, which is looking for stable accommodation for students or young professionals.

Read also: Start of the 2026 academic year in Portugal: A legal guide to student room rental agreements, Student housing Canada 2026: What is the impact of the new cap on room rentals? and Student housing shortage in Switzerland: Homestay, a vital solution for 2026

Historically, rental income (category F of the IRS) was taxed at a flat rate of 28%. In 2026, the standard rate was lowered and set at 25%. This is already a first victory for your purchasing power. However, applying this standard rate of 25% would be a strategic error if you intend to rent out for the long term. The legislator has indeed put in place an extremely powerful system of sliding scales. The longer you commit to your tenant, the lighter your tax burden becomes. This philosophy aims to stabilise the market and offer peace of mind to both the tenant and the host.

It is essential to note that renting out a room in your home in Portugal fully falls within the scope of these measures. Whether you are renting a converted outbuilding, an unoccupied master suite, or a simple student room, the income generated is eligible for these tax reductions, provided that the declaration rules are respected. We will look in detail at how these scales work and how you can, in certain cases, reduce your tax to zero.

Long-term rental IRS reduction: Detailed scales for 2026

The long-term rental IRS reduction is the heart of the new tax system. The Portuguese government has segmented the benefits based on the duration of the lease contract you sign with your tenant. At Roomlala, we often encourage our hosts to prioritise student rentals for a full academic year, or multi-year leases for young professionals, in order to maximise these benefits.

Abatements according to the lease duration

If you opt for a traditional rental contract, the 25% tax rate literally melts away as the duration of the lease increases. Here are the official scales in force for 2026:

• From 5 to 10 years: The tax rate drops from 25% to just 15%. This is a massive reduction that mechanically increases your net profitability.
• From 10 to 20 years: The rate drops to 10%. Ideal if you are hosting a trusted tenant who wishes to settle down for the long term.
• Over 20 years: The rate is reduced to a symbolic level of 5%.

Let's take a concrete example to illustrate this. Imagine that Maria, a host in Lisbon, rents out a room in her apartment for €400 per month to a master's student, with a 5-year renewable contract. Instead of paying €1,200 in IRS per year (at a 25% rate), she will only pay €720 (at a 15% rate). That is a net saving of €480 per year, simply by formalising a contract for the right duration.

The special "moderate rent" rate and total exemption (RSAA)

But the real revolution of the 2026 law lies in the affordable rent schemes. The government has introduced a special ultra-reduced rate of 10% for all so-called "moderate rent" residential contracts. To benefit from this, the rent of the room (or the entire home) must not exceed a monthly cap set at €2,300. In the context of renting a room in your home, this cap is extremely wide and allows you to almost systematically be eligible for this 10% rate.

Better still: the new Simplified Affordable Rental Regime (RSAA). If you agree to rent out your room at a rate 20% lower than the median rent in your municipality, and you sign a lease of at least 3 years, you benefit from a total IRS exemption (0% rate). For example, if João in Porto notes that the median rental for a room in his neighbourhood is €500, and he decides to offer his at €400 on Roomlala with a 3-year lease, he will pay absolutely no tax on this income. It is a win-win strategy: the tenant gets access to affordable housing, and the host maximises their net return while avoiding rental vacancies.

Portugal room rental tax 2026: How to optimise your deductions and make your space profitable?

In addition to rate reductions, the Portugal room rental tax 2026 allows you to optimise your taxable base. Indeed, the Portuguese Tax Authority (AT) allows hosts to deduct a certain number of expenses from their gross rental income. This is an often-overlooked aspect of renting in your home, but it proves to be incredibly effective in lowering the tax bill.

Deductible expenses from your gross rental income

When you rent out a part of your primary residence, you cannot deduct all the costs of the house. However, you are perfectly entitled to deduct these expenses in proportion to the rented surface area. Expenses eligible in 2026 include:

• IMI (Imposto Municipal sobre Imóveis): The equivalent of the council tax.
• Multi-risk home insurance: Mandatory and provides security for your home.
• Condominium fees: If you live in an apartment building.
• Energy certificate: Required for letting.
• Maintenance and repair work: Painting, plumbing, electrical work for the rented room.

Imagine that your apartment is 100 m² and the rented room represents 15 m², with shared access to common areas valued at an additional 10 m². You are therefore renting approximately 25% of your living space. You will be able to legally deduct 25% of your IMI bill, 25% of your condominium fees, and 25% of your insurance premium from your gross rental income before the tax is calculated. At Roomlala, we advise you to carefully keep all your invoices (faturas com NIF) to justify these deductions during your annual IRS declaration.

Enhanced appeal for tenants: an asset for hosts

Why is it so crucial to offer a proper contract? Quite simply because tenants have become extremely demanding on this point, and for good reason: the Portugal housing law 2026 also thought about them. The tax deduction ceiling on the IRS for tenants has been significantly upgraded, rising from €700 to €900 per year. A student tenant or a young professional therefore has a major financial interest in demanding an official contract and electronic receipts. By renting your room in a completely transparent way and declaring it on Roomlala, you attract the best profiles: those who are solvent, serious, and eager to settle in for the long term to benefit from their own tax advantages.

Legal points of vigilance to secure your tax benefits with Roomlala

While the legal framework is particularly generous, it requires impeccable administrative rigour in return. The Portuguese government is actively fighting against the black economy, and non-compliance with procedures leads to the immediate loss of IRS reductions, with an automatic return to the punitive standard rate, accompanied by possible fines.

The first point of absolute vigilance concerns the registration of the contract. For the long-term rental IRS reduction to apply, your lease contract must imperatively be registered on the Portal das Finanças within a maximum period of 30 days after its signing. It is also mandatory to issue electronic rent receipts (recibos de renda eletrónicos) each month via this same portal. At Roomlala, we facilitate the connection with trusted tenants, but it is up to you to finalise this simple but mandatory administrative step with the Tax Authority.

Next, it is crucial to distinguish residential renting from tourist renting. Short-term rentals under the Alojamento Local (AL) regime are strictly excluded from these tax benefits. To benefit from the reduced rates (15%, 10%, 5%, or 0% via the RSAA), the room must mandatory serve as the permanent primary residence for the tenant, or as long-term student housing. Seasonal contracts of a few weeks for holidaymakers are not eligible.

Finally, be vigilant regarding rent caps if you are aiming for the 10% rate or the RSAA exemption. Failure to comply with the maximum authorised amounts or failure to communicate the contracts to the AT retroactively cancels your benefits. In conclusion, renting out a room in your primary residence in Portugal in 2026 is a fantastic financial opportunity. By relying on a secure platform like Roomlala to find the ideal tenant and by scrupulously respecting the registration procedures, you ensure yourself a stable, sustainable, and tax-optimised additional income. Do not wait any longer to add value to your unused space and actively participate in the housing solution in Portugal!