Unauthorized construction in Greece: 2026 Guide
✦ Key Takeaways
- What it is: any construction or change of use carried out without a building permit, or in excess of one.
- What can be regularized: only unauthorized works completed before 28 July 2011, which fall into five categories.
- Deadline: for Categories 1 to 4, the deadline has been extended to 31 March 2028; Category 5 (major violations or buildings with no permit at all) has remained closed since 2020.
- New law: since 8 June 2026, Greece's new Spatial Planning and Urban Planning Code "Nikolaos Tagaras" (Law 5306/2026) has been in force. It codified the former Law 4495/2017 without creating any new general route to legalization.
- The practical takeaway: a property with unauthorized construction cannot be transferred, and cannot safely be used in any legal transaction, until the required technical and legal review — regularization and the building's electronic identity — has taken place.
What counts as unauthorized construction
Unauthorized construction is any building addition or works carried out without a building permit, in excess of the permit granted, or under a permit that has since been revoked or annulled. An unauthorized change of use, similarly, is converting the use of a space — for example, turning a basement or storage area into living space — without the required permit.
In practice, the most common violations you'll come across in a property are:
- an enclosed semi-outdoor space or balcony turned into a room,
- an attic or mezzanine not shown on the approved plans,
- exceeding the permitted building coverage, floor area, or height,
- internal layout changes or added space (e.g. an extra bathroom),
- a change of use without a permit (e.g. a basement or pilotis turned into living space).
The key point: an unauthorized construction issue is rarely just a paperwork matter. It's the single most common reason a property transfer falls through at the last minute — which is exactly why it's worth understanding before you get anywhere near a notary.
Deadline for regularization: 31 March 2028
The single most important date for any owner is the cut-off for filing. For Categories 1 to 4, the regularization deadline has been extended from 31 March 2026 to 31 March 2028.
Two things to know from the outset:
- The cut-off date is 28 July 2011. Only unauthorized constructions or changes of use that were completed before this date can be brought into the scheme at all.
- Category 5 remains closed. For "major" violations — overruns of more than 40%, or buildings with no permit whatsoever — the option to regularize has been suspended since October 2020 and has not been reinstated on a general basis.
Tip — Terra Property: The later you file, the higher the fine: the law provides for escalating surcharges depending on when the declaration is submitted. If you're planning to sell or transfer the property, don't wait until 2028 — the inspection and regularization process takes time, and leaving it late rarely works out cheaper.
What changed in 2026: the new Code (Law 5306/2026)
Since 8 June 2026, Greece's new Spatial Planning and Urban Planning Code "Nikolaos Tagaras" (Law 5306/2026) has been in force. It brought the former Law 4495/2017, the New Building Regulation, and dozens of other pieces of legislation together into a single text.
An important clarification: this is not a new general route to legalizing unauthorized construction. The categories, fines, and deadlines that were already in place remain unchanged — what has mainly changed is the numbering of the articles, as the provisions of the former Law 4495/2017 were incorporated into the new Code. In practice, everything that applied to unauthorized construction continues to apply; the correct legal reference simply now points to the Code's articles.
Regularization vs. legalization: what's the difference
In everyday language, the two terms are often used as if they were synonyms. Legally, however, they are not always the same thing — and the distinction matters for what you actually end up with.
- Regularization (inclusion in the scheme): you declare the violation and, by paying the fee and the fine, demolition and penalties are suspended for 30 years. In some cases (very old constructions, or minor violations) the exemption from demolition is permanent. In every case, regularization does not automatically turn the unauthorized construction into a fully legal, "clean" building.
- Legalization: a legalization permit is issued when the construction can genuinely be brought into compliance — that is, it meets (or can be made to meet) the applicable planning regulations. This is the "fuller" outcome, but it isn't always available.
In plain terms: legalization assumes the construction can actually become lawful; regularization simply "freezes" the consequences. When someone tells you a property is "regularized," that doesn't automatically mean it's also legalized.
Which unauthorized constructions can be regularized: the cut-off and the exceptions
The scheme covers unauthorized constructions whose load-bearing structure was completed, and unauthorized changes of use that took place, before 28 July 2011.
Even when the date is met, there are areas and circumstances where inclusion in the scheme is not permitted. As a rule, unauthorized constructions are not regularized when they are located:
- in forests or forest land,
- on the coastline (aigialos) or the former coastline,
- in streambeds or sensitive coastal or water-related zones,
- in publicly designated open spaces within an approved town plan,
- in Zone A archaeological sites,
- in areas subject to expropriation/realignment, or outside the limits of buildable plots, under certain conditions.
Because these exceptions involve many specific scenarios and local parameters, classifying a property as "not eligible" should always be confirmed by a qualified engineer.
The 5 categories of unauthorized construction
The law sorts unauthorized constructions into five categories. One important distinction: Categories 1 and 2 are defined by the date of construction, while Categories 3, 4 and 5 are defined by the severity of the violation.
| Category | What it covers | What applies |
|---|---|---|
| 1 | Residential constructions completed before 9 June 1975 | Fee of €250, no special fine — permanent exemption from demolition |
| 2 | Unauthorized works before 1 January 1983 | Fee* + unified special fine |
| 3 | Minor violations (e.g. small reduction in planted area, façade insulation, minor changes to balconies) | Fee of €250, no special fine |
| 4 | Medium-sized overruns (up to 40% in coverage/floor area and up to 20% in height) | Fee* + special fine — 30-year suspension of penalties |
| 5 | Major overruns (above 40%) or buildings with no permit at all | Inclusion in the scheme closed since 2020 — not regularized as a rule |
What applies specifically to Category 5
This is the category that confuses most people. It covers the "heavier" violations — major overruns, or structures with no permit at all. The option to bring these into the scheme has been suspended since October 2020 and has not been reinstated on a general basis; since then, it has applied only to a limited set of specific cases. In practice, a Category 5 violation today creates a serious obstacle to transferring or making use of the property, unless it falls under a specific exception.
How to find out if your property has unauthorized construction
Before any move to sell or transfer a property, the first step is finding out whether — and what — needs to be regularized. The check is carried out by an engineer and rests on three things:
- Building permit and approved plans: compared against the property's actual current condition.
- On-site inspection: the engineer measures and records what actually exists in the space today.
- Electronic Building Identity (EBI): the property's "passport," mandatory for every transfer, which records the building's true, lawful status.
As a quick reference, the table below shows whether some of the most common cases typically require regularization:
| Case | Does it typically need regularization? |
|---|---|
| Enclosed semi-outdoor space | Yes |
| Attic/mezzanine not on the plans | Yes |
| Enclosed pilotis | Yes |
| Basement or storage space converted to living space | Yes |
| Change of use | Yes |
| Extra floor / addition | Yes |
| Pergola | Depends* |
| Minor layout change | Depends* |
| Balcony extension | Depends* |
Step-by-step: the regularization process through TEE
The declaration is filed electronically through the system of the Technical Chamber of Greece (TEE) and is linked to the property's Electronic Building Identity. The typical process is:
- Engaging an engineer — they take on the inspection and the filing.
- On-site inspection of the property.
- Checking the building permit and approved plans against the actual condition.
- Calculating the fine through the electronic system.
- Filing the declaration in the TEE system.
- Paying the fee and fine (in full or in instalments).
- Completion of the inclusion in the scheme and updating the property's records.
Documents needed for regularization
Before you start, it's worth having the following gathered together:
- Title deeds
- E9 tax declaration
- Building permit (where one exists)
- Approved plans / floor layouts
- Topographical survey
- Photographs of the property
- Evidence of the construction's age (e.g. aerial photographs, older documents)
- Engineer's technical report
The exact documents required vary by category and by case; your engineer will confirm exactly what your property needs. If you're preparing for a sale, our guide to property transfer documents in Greece walks through the broader paperwork the deal itself will require.
Cost of regularizing unauthorized construction
The total cost isn't a single figure — it's the sum of several components:
- Fee: a flat €250 for Categories 1 and 3; scaled (€250–€10,000) according to floor area for the others.
- Unified special fine: the main cost. As a simplified rule of thumb, it's calculated as floor area × zone price × 15% × coefficients that depend on the type and age of the violation.
- Engineer's fee: for the inspection, surveys, plans, and the filing itself.
- Plans/survey costs: where new studies are required.
Worked example
For an unauthorized construction of 50 sq.m. in an area with a zone price of €2,000/sq.m., the basic calculation of the special fine is:
50 sq.m. × €2,000 × 15% = €15,000 (base amount)
The final figure is shaped by the applicable coefficients (age, type of violation, etc.) and may come out lower or higher. On top of this, you'd add the fee (€250 here, for a construction up to 100 sq.m.) and the engineer's fee.
The law also provides for some relief: payment in up to 100 instalments, a 20% discount for paying in full upfront, and a 10% discount for an advance payment of 30% of the fine.
Engineer's fee
There's no single "minimum" rate. The fee depends on the property, the type and complexity of the violation, the surveys and plans required, and the level of professional liability the engineer is taking on. Always ask for a detailed quote before commissioning the work.
How unauthorized construction affects a property's value and its transfer
This is where the real stakes lie for an owner. Unauthorized construction isn't just a legal loose end — it has a direct effect on the property's value and how easily it can be sold:
- It lowers market value: buyers discount the price to account for the cost and time of regularization.
- It narrows the pool of buyers: anyone relying on a mortgage is often excluded, since banks won't lend against properties with unresolved unauthorized construction — on top of the usual costs buyers already budget for when purchasing in Greece.
- It delays or derails the transfer: without an engineer's certificate and an Electronic Building Identity, the notary cannot proceed with the deed.
- It creates leverage in negotiation: the violation becomes a bargaining chip used to push the price down.
The new Code (Law 5306/2026) reaffirmed this strict framework: as confirmed by Greece's tax authority (AADE), any transfer or creation of a real right over a property with unauthorized constructions or changes of use is prohibited and is absolutely void (Article 367, Law 5306/2026). The only way through is prior regularization, where permitted, and completion of the property's Electronic Building Identity.
Expert View — Terra Property: In practice, the biggest cost of unauthorized construction is rarely the fine itself. It's the lost time and the lost negotiating position. A buyer who discovers a violation midway through a deal will either walk away or demand a discount far larger than the cost of regularization would have been. Anyone planning to sell or transfer a property in the coming years comes out ahead by regularizing before putting it on the market — not after finding a buyer.
This applies just as much within families: if the property is moving to a child or relative rather than a buyer, our guide to parental property transfers in Greece covers the tax rules and legal steps involved.
Common mistakes owners make
- "My place is old, so I'm fine." Age helps determine the category, but it doesn't remove the obligation to file a declaration.
- "It's on my E9, so it's legal." The E9 is a tax declaration — it has no bearing on planning legality.
- "No one's checking, so I don't need to bother." The check arrives, without fail, the moment you try to transfer the property — and by then, time is against you.
- "I'll deal with it once I find a buyer." Regularization typically takes weeks or months; buyers rarely wait that long. The same is true in reverse — many owners only discover a planning issue when a property passes through inheritance or a family transfer; our guide to inheriting property in Greece covers what that process involves.
- "The notary will sort it out." A notary cannot proceed with the deed without an engineer's certificate and an Electronic Building Identity.