The Building Identity Certificate (HTK) has now become an essential procedure for every property owner who wishes to proceed with a sale, legalization, or new building permit. It is essentially a complete “digital file” of the property, containing all the necessary documents and data, with the goal of ensuring transparency and security in real estate transactions.
Correct and timely registration of the HTK is not just a formal obligation; it guarantees that the property is fully legal and ready to be utilized, without the risk of hidden violations or missing documentation.
When the Building Identity Certificate is Mandatory
The Building Identity Certificate has now been established as mandatory for a series of cases related to the management and transfer of real estate. Every time a property transaction takes place, whether it concerns a residence, a commercial space, or a plot of land, the existence of an updated HTK is necessary in order for the contract to be completed.
In addition, when an owner proceeds with the legalization or settlement of unauthorized constructions, the HTK serves as the official file where the related changes are recorded. It is also required when a new building permit or small-scale permit is issued, ensuring that there is a complete record of the property and its development. Finally, its connection with other documents, such as the Energy Performance Certificate (EPC), makes it a tool that touches almost every aspect of real estate.
Overall, the completion and registration of the HTK is required in cases such as:
- Property sale (residence, commercial building, plot of land).
- Legalization or settlement of unauthorized constructions.
- Issuance of a new building permit or small-scale construction permit.
- Entry of data in the Building Identity Certificate for buildings that are about to obtain an Energy Performance Certificate (EPC).

Required Documents for the Building Identity Certificate
In order to correctly complete the HTK, a set of documents that reflect the actual and legal status of the property is required. At the top of the list is the building permit along with any revisions, since it forms the basic legal framework of the building’s existence. Equally important are the floor plans, sections, and architectural drawings, which accurately show the layout and features of the property.
The E9 tax form of the owner is also often required, to confirm that the details declared to the tax authorities match the actual property data. If an Energy Performance Certificate (EPC) has been issued, it is also included in the file, while the engineer issues a certificate of no violations or records any legalizations that have been carried out. Finally, property photographs are requested for full documentation, while in some cases a Structural Adequacy Study (SAS) is required, especially when the property includes violations that affect the load-bearing structure.
In summary, the main documents usually required are:
- Building permit and any revisions.
- Floor plans, sections, and architectural drawings.
- Owner’s E9 tax form (to confirm ownership details).
- Energy Performance Certificate (EPC).
- Engineer’s certificate of no violations.
- Property photographs.
- In certain cases, Structural Adequacy Study (SAS), as required by Law 4495/2017.
Registration Process in the TEE System
The completion of the HTK is carried out exclusively by an authorized engineer through the electronic system of the Technical Chamber of Greece (TEE). The process begins with the collection of all required documents, something that often requires cooperation with services or the retrieval of old files from the owner. The engineer then performs a detailed legality check to ensure that there are no discrepancies between the drawings, the permit, and the actual state of the property.

Once the material has been gathered and verified, the engineer logs into the electronic system and proceeds with the registration of all data, uploading the documents and filling in the relevant forms. The process is completed with the issuance of the HTK, which receives a unique identification number. This number accompanies the property in every future transaction, making the HTK a living and continuously updated file.
- Collection of all required documents from the owner.
- Legality check and identification of discrepancies.
- Engineer’s login to the TEE system.
- Registration of all documents and property details.
- Issuance of the Building Identity Certificate with a unique number.
The Importance of the Building Identity Certificate for Owners and the Real Estate Market
The Building Identity Certificate is not simply another administrative document. It is a process that radically changes the way we deal with real estate in Greece. For decades, the lack of a central digital record resulted in countless ambiguities, omissions, and often serious problems during property transactions. The HTK fills this gap by creating a “lifetime file” for each building, bringing together all data from the original building permit to the most recent modifications.
For the property owner, this means greater transparency but also greater security. Having a complete and updated file ensures that the property is ready for any future transaction without surprises. On the other hand, the buyer has in their hands all the data on the actual condition of the property, which minimizes the risk of hidden issues.
Although the process may seem complex, in reality it is an organized workflow that, with the proper guidance from an engineer, can be completed smoothly. The key lies in the cooperation between the owner and the engineer, so that all documents are collected on time without omissions. In many cases, delays in completing the process are due solely to the difficulty of retrieving old documents.
It is also important to emphasize that the HTK is not a static document. It is a living file that must be updated with every new intervention or modification of the building. This ensures that the record always remains current, offering security not only to the owner but also to future buyers.
In the final analysis, the Building Identity Certificate is an investment in the value and transparency of the property. It embodies the philosophy that real estate is not just a means of housing or investment, but an asset that requires responsibility, accuracy, and consistency in its management.
Frequently Asked Questions (FAQ)
Is the Building Identity Certificate required for all properties?
Yes, the HTK applies to all categories of buildings, with variations in the required documents.
How much does it cost?
The cost depends on the size of the property, the completeness of the file, and any missing plans or permits.
How long does it take to complete?
Usually within a few weeks, provided all documents are available.
Contact Us
If you need support for the completion of the Building Identity Certificate, our team undertakes the entire process, from document verification to final registration in the TEE system.




