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

Do you have a spare room in your house or apartment in Portugal? In an economic environment 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 to host a tenant can sometimes raise questions, especially regarding administrative and tax matters. Good news: the tax rules for renting a room in Portugal in 2026 have been completely overhauled by the government to your significant advantage. To encourage the supply of housing and rooms for long-term stays, the Portuguese state has deployed an arsenal of highly incentivising tax measures. Gone are the days when taxes ate up the majority of your rental income! Today, renting out a room in your home in Portugal has never been safer, more legal, and above all, 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 personal income tax (IRS), and secure your process through long-term leases.

Housing Law Portugal 2026: The new tax landscape for hosts

To understand the opportunity available to you this year, we must look at the recent Portugal Housing Law 2026. Faced with the 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 traditional residential renting. At Roomlala, we observe that this transition fits perfectly with the expectations of our community, which is looking for stable accommodation for students or young professionals.

See also: 2026 academic year in Portugal: The legal guide to student room rental agreements, Student accommodation Canada 2026: What is the impact of the new cap on room rentals? and Student housing shortage in Switzerland: Homestays as a vital solution for 2026

Historically, rental income (Category F of the IRS) was taxed at an autonomous 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 25% rate would be a strategic error if you intend to rent long-term. The legislator has implemented 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 provide peace of mind to both the tenant and the hosting host.

It is essential to note that renting a room in your home in Portugal falls fully within the scope of these measures. Whether you are renting a converted outbuilding, a spare 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 some cases, reduce your tax to zero.

Long-term rental IRS reduction: The 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 over a full academic year, or multi-year leases for young professionals, to maximise these benefits.

Abatements according to lease duration

If you choose a traditional rental contract, the 25% tax rate drops significantly as the lease duration 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 automatically increases your net profitability.
• From 10 to 20 years: The rate drops to 10%. Ideal if you are hosting a trusted tenant who wants to settle in for the long term.
• More than 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 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 annually (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 "moderate rent" special 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 residential contracts known as "moderate rent". To benefit from this, the rent for the room (or the entire home) must not exceed a monthly ceiling set at €2,300. When renting a room in a home, this ceiling is extremely generous and almost always allows you to be eligible for this 10% rate.

Even better: the new Simplified Affordable Rental Regime (RSAA). If you agree to rent 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 rent for a room in his neighbourhood is €500, and he decides to offer his on Roomlala at €400 with a 3-year lease, he will pay absolutely no tax on that 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.

Taxation for renting a room in Portugal 2026: How to optimise your deductions and make your space profitable?

Beyond rate reductions, the 2026 tax system for renting a room in Portugal 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 homestays, but one that proves highly effective in lowering the tax bill.

Expenses deductible from your gross rental income

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

• IMI (Imposto Municipal sobre Imóveis): The equivalent of property tax.
• Comprehensive home insurance: Mandatory and provides security for your home.
• Condominium fees: If you live in an apartment building.
• Energy certificate: Required for putting a property on the rental market.
• Maintenance and repair work: Painting, plumbing, electricity 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 out 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 keep all your invoices (faturas com NIF) carefully to justify these deductions during your annual IRS declaration.

Enhanced attractiveness for tenants: an asset for hosts

Why is it so crucial to offer a proper contract? Simply because tenants have become extremely demanding on this point, and for good reason: the Portugal Housing Law 2026 also considered them. The tax deduction ceiling on the IRS for tenants has been significantly increased, from €700 to €900 per year. A student or young professional tenant therefore has a major financial interest in demanding an official contract and electronic receipts. By renting your room in a totally transparent and declared manner on Roomlala, you attract the best profiles: those who are solvent, serious, and eager to settle in for the long term to take advantage of their own tax benefits.

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 underground economy, and failure to follow procedures leads to the immediate loss of IRS reductions, with an automatic return to the standard punitive rate, accompanied by potential fines.

The first absolute point of vigilance concerns contract registration. For the long-term rental IRS reduction to apply, your lease contract must be registered on the Portal das Finanças within a maximum of 30 days after signing. It is also mandatory to issue electronic rent receipts (recibos de renda eletrónicos) each month via this same portal. At Roomlala, we make it easy to connect 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 be the tenant's permanent primary residence or long-term student accommodation. Seasonal contracts of a few weeks for holidaymakers are not eligible.

Finally, be vigilant about rent ceilings if you are aiming for the 10% rate or the RSAA exemption. Failure to respect the maximum permitted amounts or failure to communicate contracts to the AT will retroactively cancel 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 strictly following the registration procedures, you ensure yourself a stable, sustainable, and tax-optimised additional income. Do not wait any longer to add value to your spare space and actively participate in the housing solution in Portugal!