Gas inspections are mandatory in Portugal under Article 21 of Decreto-Lei n.º 97/2017, de 10 de agosto (DL 97/2017), as amended by Lei n.º 59/2018, de 21 de agosto, required every 5 years. For installations completed after 21 August 2018, the first inspection is due when the installation reaches 10 years. For installations pre-dating that date, the first inspection deadline is 26 August 2028 or when the installation reaches 20 years, whichever comes first. Non-compliance carries fines from €250 to €3,500 for individuals and, after a 3-month DGEG grace period, permanent gas supply disconnection. APEG dissolved on 31 December 2025. InspectOS carries out certified gas inspections for less than the minimum fine, with the Boletim de Inspeção issued on the same day.
Table of Contents
- What is the mandatory gas inspection in Portugal?
- Who is required to have a gas inspection?
- How often is gas inspection required in Portugal?
- What happens if you miss the gas inspection deadline?
- What did the dissolution of APEG change?
- What does a certified gas inspection cover?
- How much does a gas inspection cost in Portugal?
- Gas inspection when buying or selling property
- How does the InspectOS gas inspection process work?
- Frequently Asked Questions
- Conclusion
What is the mandatory gas inspection in Portugal?
The mandatory gas inspection in Portugal is a periodic safety assessment of natural gas and LPG installations required under DL 97/2017 (as amended by Lei 59/2018), with timelines depending on whether the installation pre- or post-dates 21 August 2018, to protect occupants from leaks, carbon monoxide poisoning, and fire.
Decreto-Lei n.º 97/2017, de 10 de agosto (DL 97/2017), as amended by Lei n.º 59/2018, de 21 de agosto, establishes the legal framework governing the quality and safety of gas installations in Portuguese buildings. The law requires all property owners and landlords with gas installations to arrange periodic inspections by DGEG-accredited Entidades Inspetoras de Gás (EIG - authorised gas inspection entities).
This is not a voluntary safety check. It is a legal obligation that falls on the property owner regardless of whether the property is occupied or rented. In a rental property, the legal responsibility rests with the landlord unless there is a specific written agreement to the contrary.
The outcome of every inspection is recorded in a Boletim de Inspeção (gas safety certificate) - the legal document that proves compliance with DL 97/2017. Without a valid Boletim de Inspeção, the installation is not legally compliant and the gas distributor can be notified to suspend supply after the grace period defined in the law.
For foreign buyers completing purchases remotely: no notary, estate agent, or câmara municipal (local authority) checks gas inspection status before a property sale completes. Since Simplex Urbanístico (DL 10/2024) eliminated mandatory municipal verification at the point of sale, a buyer can complete a legally clean transaction and inherit a non-compliant gas installation on the day of the escritura (deed of sale).
Who is required to have a gas inspection?
The periodic gas inspection obligation covers all residential properties with gas installations, with first-inspection timelines varying by installation date: after 10 years for post-August 2018 installations, and by 26 August 2028 (or at 20 years, whichever comes first) for pre-August 2018 installations, plus all commercial, hospitality, educational, health, industrial and other non-residential uses (UT III-XII) with installations older than 3 years.
The obligation applies to any property owner with a natural gas or networked LPG installation. The most common situations are:
Owner-occupied property with gas: For installations completed after 21 August 2018, the first inspection is due when the installation reaches 10 years. If the installation pre-dates 21 August 2018, the first inspection deadline is 26 August 2028 or when the installation reaches 20 years, whichever comes first. Subsequent inspections are every 5 years.
Rented property: The legal responsibility lies with the landlord. Tenants have the legal right to request a valid Boletim de Inspeção before signing a rental contract. A rental contract entered into with a non-compliant gas installation exposes the landlord to fines and potential civil liability in the event of an incident.
Alojamento Local (short-term rental): AL properties are subject to the same gas obligations as residential properties. For AL properties hosting more than 10 guests, full SCIE (fire safety systems) compliance is mandatory, including certification of gas installations.
Condominiums with centralised gas: Where gas serves a building via a collective installation in the common areas, the obligation for those common areas falls on the condominium, represented by the building administrator. The inspection of individual installations inside each unit is the responsibility of each unit owner.
Pre-21 August 2018 installations: DGEG has confirmed that all installations pre-dating 21 August 2018 that have not yet been inspected under DL 97/2017 must complete their first inspection by 26 August 2028 or when the installation reaches 20 years, whichever comes first.
How often is gas inspection required in Portugal?
Residential gas inspection timelines depend on installation date: post-21 August 2018 installations require a first inspection after 10 years; pre-21 August 2018 installations must be inspected by 26 August 2028 or at 20 years, whichever comes first - then every 5 years under DL 97/2017, Art. 21, as amended by Lei 59/2018.
The required frequency depends on the type of installation:
| Installation type | Required frequency | Legal basis |
|---|---|---|
| Residential (installed after 21 Aug 2018) | First inspection after 10 years; then every 5 years | DL 97/2017 with Lei 59/2018 |
| Residential (installed before 21 Aug 2018) | First inspection by 26 Aug 2028 or at 20 years (whichever first); then every 5 years | DL 97/2017, DGEG confirmed |
| Commercial, hospitality, educational, health, industrial and other non-residential uses (UT III-XII) | Every 3 years | DL 97/2017, Art. 21(1)(a) |
One point frequently misunderstood: the periodic inspection is not the same as the inspection required when installing new appliances or modifying an existing installation. These are separate obligations. Installing a new water heater does not substitute for the periodic inspection of the full installation.
What happens if you miss the gas inspection deadline?
Missing the mandatory gas inspection deadline in Portugal results in fines from €250 to €3,500 for individuals under DL 97/2017, Art. 29, followed by permanent gas supply disconnection after a 3-month DGEG notification period.
The enforcement regime under DL 97/2017 operates in two stages:
Stage 1: Fine. The absence of a valid periodic inspection constitutes an administrative offence punishable by a fine of €250 to €3,500 for individuals and €450 to €40,000 for companies (DL 97/2017, Art. 29(1)). DGEG applies the fine following an inspection or complaint.
Stage 2: Supply disconnection. After a DGEG notification, the owner has a 3-month grace period to regularise the situation. If no valid inspection is produced within that period, the gas distributor is notified to proceed with permanent supply disconnection (DL 97/2017, Art. 21(3)). Disconnection is not reversed by paying the fine. It requires a new inspection with a compliant result, a new Boletim de Inspeção, and a formal request to the distributor to restore supply.
There is no public DGEG registry of which individual properties hold a valid Boletim de Inspeção. As a buyer, you have no way of knowing whether the property you are considering is compliant unless you request the document directly from the vendor or commission an independent inspection before the escritura.
What did the dissolution of APEG change?
APEG (Associação Portuguesa de Empresas de Gás) dissolved on 31 December 2025, removing the sector's main information reference point and leaving DGEG as the sole competent authority for all gas installation matters in Portugal.
APEG was the industry association that provided guidance on gas safety obligations, maintained information for property owners, and published lists of authorised inspection entities. With the dissolution on 31 December 2025, that reference point no longer exists. Many articles and pages that still appear in search results reference APEG or link to the apeg.pt portal, which now returns a 404 error. Outdated information about procedures, timelines, and authorised entities continues to circulate and is a genuine source of confusion.
The sole competent authority for everything relating to gas inspections in Portugal is now DGEG. The register of EIGs authorised to carry out inspections under DL 97/2017 is maintained and updated by DGEG at dgeg.gov.pt.
InspectOS is a DGEG-accredited EIG for gas inspections under DL 97/2017. The Boletim de Inspeção issued by InspectOS carries full legal validity and is recognised by all gas distributors operating in Portugal. For property owners who were previously relying on APEG-affiliated entities, it is worth confirming that the specific entity they used is still listed on the current DGEG register.
What does a certified gas inspection cover?
A DGEG-certified gas inspection under DL 97/2017 assesses installation tightness, appliance condition, ventilation and flue gas evacuation, and carbon monoxide levels, concluding with a Boletim de Inspeção issued on the same day.
Installation tightness. A pressure test is carried out on the entire pipework from the connection point to the outlet of each appliance. Any leak, however minor, constitutes a Grade 3 anomaly (immediate safety risk) requiring supply interruption until repaired.
Gas appliances. Visual and functional check of all gas-connected appliances: water heaters (esquentadores), boilers (caldeiras), cookers, stoves, and gas storage heaters. The inspector verifies condition, manufacture date, and compliance with applicable technical standards.
Ventilation and flue gas evacuation. Check of ventilation openings in rooms housing gas appliances and of flue gas evacuation systems (chimneys, evacuation pipes). Blocked or undersized ventilation is the primary cause of carbon monoxide poisoning in residential properties.
Carbon monoxide (CO) detection. Measurement of CO concentration in rooms with gas appliances. Concentrations above safety thresholds constitute a critical anomaly requiring immediate evacuation. InspectOS includes CO detection with calibrated equipment as standard on every inspection.
Anomaly classification. All findings are classified by grade: Grade 1 (advisory, no immediate risk), Grade 2 (intervention required in the short term), Grade 3 (immediate risk, supply must be interrupted). The Boletim de Inspeção records all anomalies by grade with recommended actions. For a complete pre-purchase assessment, structural condition is evaluated separately. A structural and seismic inspection Portugal covers the building envelope risks that a gas inspection does not assess.
How much does a gas inspection cost in Portugal?
A DGEG-certified gas inspection in Portugal includes the Boletim de Inspeção issued on the same day, with coverage across mainland Portugal. Get a quote at inspectos.pt.
For landlords who want to consolidate compliance in a single appointment, the Landlord Compliance Pack combines gas inspection, electrical inspection, and energy performance certificate in one visit.
For buyers conducting pre-purchase due diligence, the gas inspection can be added to the pre-purchase property inspection or the Simplex Safe inspection in the same visit at no additional call-out charge.
Against fines of up to €3,500 and the cost of supply disconnection and restoration, gas inspection is the lowest-cost path to legal compliance and the most straightforward element of any pre-purchase due diligence process.
Regularise your gas compliance before DGEG notifies you. InspectOS gas inspection, Boletim de Inspeção issued the same day.
Gas inspection when buying or selling property
The absence of a valid Boletim de Inspeção transfers to the buyer at the escritura under DL 10/2024, with no post-sale legal recourse - making gas inspection verification a mandatory step in any Portuguese property purchase.
Gas inspection status is not verified by the notary before the escritura. Since DL 10/2024 abolished the mandatory licença de utilização (use permit) as a prerequisite for the escritura, no public authority checks the technical condition of the property before the sale completes. The buyer signs and inherits everything.
For buyers: Request the Boletim de Inspeção from the vendor before signing the CPCV (Contrato-Promessa de Compra e Venda - the promissory purchase contract with deposit). If the Boletim does not exist or has expired, you have documented grounds to negotiate a price reduction corresponding to the regularisation cost, or to require the vendor to carry out the inspection as a condition of the sale. The property inspection before signing the CPCV guide explains how to make gas compliance a contractual condition of the sale.
For sellers: A valid Boletim de Inspeção removes a potential negotiation point and demonstrates that the property is in legal compliance. Given that the inspection costs less than the minimum fine for non-compliance, there is no rational case for leaving this unresolved before listing.
Gas installation efficiency also contributes to a property's overall energy performance rating. Buyers purchasing low-rated properties should review EPBD compliance Portugal 2026. 29 May 2026 is the EU transposition deadline for Directive 2024/1275 rather than a date on which obligations attach to an individual property. Portugal transposed the directive in part through DL 11/2025 and the remainder is pending.
For a complete technical assessment before purchase, the pre-purchase property inspection covers gas installation, electrical installation, structure, and urban planning compliance in a single report delivered within 48 hours. The property due diligence checklist for Portugal lists gas certificate verification alongside the four mandatory documents every buyer should confirm before committing. For document-level due diligence, RealOS's digital cross-referencing of property documents can identify red flags before you commit to a site visit. Already have a RealOS report? If your score indicates elevated risk, confirm physically with an InspectOS inspection.
How does the InspectOS gas inspection process work?
The InspectOS gas inspection runs in three steps: online booking, visit by a DGEG-accredited technician, and Boletim de Inspeção issued on the same day.
Step 1: Book online. Choose your date and location on the InspectOS booking page. InspectOS operates in Lisbon, Porto, the Algarve, and nationwide.
Step 2: DGEG-accredited technician visits. The InspectOS technician visits the property and conducts the full inspection: tightness test, appliance check, ventilation and flue assessment, and CO measurement. A standard T2-T3 apartment inspection takes 45 to 90 minutes.
Step 3: Boletim de Inspeção issued the same day. The Boletim is delivered digitally on the day of the visit. It carries full legal validity with DGEG and all gas distributors. It records all anomalies by grade and provides specific recommendations for any corrective works required.
For property owners who need gas inspection alongside other compliance services, see the full services and pricing page for current bundle options.
Frequently Asked Questions
Do you need a gas safety certificate to sell a house in Portugal?
There is no single pre-sale gas certificate the way the UK treats a CP12 at the point of a tenancy. What Portuguese law requires is that the installation itself is within its inspection period under DL 97/2017, and the document proving that is the Boletim de Inspeção de Gás. In practice a buyer's lawyer or lender will ask for it, and an installation that is out of period becomes the buyer's problem the moment the escritura is signed. Sellers who cannot produce a valid Boletim are the ones who end up negotiating on price.
How much does a gas safety certificate cost in Portugal?
The right way to think about the cost is against what non-compliance costs. Under DL 97/2017 Art. 29.º the fine runs from €250 to €3,500 for an individual and from €450 to €40,000 for a company, and DGEG can order the supply cut off after its notice period expires. The certificate is a fraction of the lower end of that range. Price depends on the installation type and the number of appliances, so it is quoted per property rather than from a fixed list.
Is the Portuguese gas inspection the same as a UK CP12?
No, and the differences matter more than the similarity. In the UK, the Gas Safety (Installation and Use) Regulations 1998, Regulation 36, oblige a landlord to arrange a gas safety check at intervals of no more than 12 months, carried out by a Gas Safe registered engineer, with the record given to tenants within 28 days. Failure is a criminal offence under the Health and Safety at Work etc. Act 1974, carrying an unlimited fine and up to six months' imprisonment.
Portugal runs a different regime. DL 97/2017 sets the cycle at 5 years for residential installations and 3 years for non-residential use types, the inspection is carried out by an Entidade Inspetora de Gás accredited by the DGEG rather than by a Gas Safe engineer, and the document produced is the Boletim de Inspeção rather than a CP12. Enforcement is administrative: a coima of €250 to €3,500 for individuals, then supply disconnection after the DGEG grace period. A British landlord arriving in Portugal on a twelve-month mental clock is working to the wrong calendar in both directions: less frequent, and enforced by a different authority against a different document.
Do homeowners need a gas safety certificate in Portugal?
The obligation applies to all homes with natural gas or networked LPG installations. For installations completed after 21 August 2018, the first inspection is due at 10 years. For installations pre-dating that date, the first inspection deadline is 26 August 2028 or when the installation reaches 20 years, whichever comes first. Properties with no gas installation are not covered by DL 97/2017.
What is a gas safety certificate, and what is the Boletim de Inspeção?
The Boletim de Inspeção is the legal document issued by a DGEG-accredited EIG after a periodic gas inspection. It proves that the installation was inspected, records the outcome and any anomalies found, and is the only document that demonstrates compliance with DL 97/2017. Without a valid Boletim, the installation is in legal default.
How do you get a gas safety certificate in Portugal now APEG has dissolved?
APEG dissolved on 31 December 2025. The sole competent authority for all matters relating to gas installations in Portugal is now DGEG (Direção-Geral de Energia e Geologia). The current list of authorised EIGs is maintained at dgeg.gov.pt. Any APEG-era information about authorised entities should be cross-checked against the current DGEG register.
How long does a gas safety certificate last, and what is my first deadline?
Installations pre-dating 21 August 2018 that have never been inspected under DL 97/2017 must complete their first inspection by 26 August 2028 or when the installation reaches 20 years, whichever comes first - per DGEG's confirmed transitional deadline. After that point, the installation will be in direct non-compliance subject to fines and potential supply disconnection.
Can I have the gas inspection done at the same time as a pre-purchase property inspection?
Yes. InspectOS can carry out the gas inspection alongside the Pre-Purchase Inspection or the Simplex Safe inspection in a single visit at no additional call-out charge. This is the most efficient way to assess the full technical and compliance condition of a property before signing the CPCV.
Who pays for the gas inspection in a rented property?
The legal responsibility for arranging and funding the periodic gas inspection lies with the landlord, unless there is a specific written agreement to the contrary in the rental contract. Tenants have the right to request the valid Boletim de Inspeção from the landlord.
Does the gas inspection cover the boiler and water heater?
Yes. The inspection covers all gas-connected appliances including water heaters (esquentadores), boilers (caldeiras), cookers, stoves, and gas storage heaters. The technician checks condition, manufacture date, compliance with technical standards, and carries out CO detection in all rooms with gas appliances.
What is the difference between a gas inspection and an energy performance certificate?
These are two entirely separate legal obligations. The mandatory gas inspection (Boletim de Inspeção) is required under DL 97/2017 and assesses the safety of the gas installation. The energy performance certificate (certificado energético) is required under Decreto-Lei n.º 101-D/2020 and rates building energy efficiency. Both are mandatory for property sales and rentals and can be arranged in the same visit.
Conclusion
Gas inspection compliance in Portugal is more nuanced than it appears: the timeline depends on when the installation was completed, not just its age. For all pre-21 August 2018 installations, the first inspection deadline is 26 August 2028 or at 20 years, whichever comes first. For post-21 August 2018 installations, the trigger is 10 years. After the first inspection, all installations require renewal every 5 years. With APEG dissolved and its information resources offline, property owners need to verify their obligations directly through DGEG.
InspectOS carries out DGEG-certified gas inspections with the Boletim de Inspeção issued on the same day and coverage across mainland Portugal. For landlords, the Landlord Compliance Pack covers gas, electrical, and energy certificate. For buyers, the pre-purchase property inspection includes gas inspection with a complete technical report within 48 hours. For foreign buyers unfamiliar with Portuguese compliance requirements, the complete guide for foreign buyers in Portugal covers gas certificate verification alongside all other mandatory purchase checks.
Updated August 2026 | Reviewed by the InspectOS Engineering Team | OE Certified · DGEG Accredited | InspectOS Portugal
Sources: Decreto-Lei n.º 97/2017, de 10 de agosto; Lei n.º 59/2018, de 21 de agosto; Decreto-Lei n.º 10/2024, de 8 de janeiro; Decreto-Lei n.º 101-D/2020; DGEG - Direção-Geral de Energia e Geologia; dgeg.gov.pt/faqs; ADENE Energia em Números 2025.