The ΑΤΑΚ (the property’s 9- to 11-digit number from the Ε9 form) property number: what it is and where to find it
The official ΑΑΔΕ service «Δήλωση Ε9 / ΕΝΦΙΑ». That is where you read the number; here is what it means and where it is actually needed.
The ΑΤΑΚ is the property identification number ΑΑΔΕ assigns to each right declared in the Ε9. You read it in myAADE (Taxisnet), in column 1 of your property's row in your own Ε9, and it has 9 to 11 digits. In the lease declaration the field is optional and becomes mandatory only under the clause of article 111 of Law 4446/2016.
Last updated: September 2026
In mamaXO's free lease template the ΑΤΑΚ is an optional field — exactly as it is at ΑΑΔΕ. If you do not have it to hand, the agreement still comes out.
What the ΑΤΑΚ is and where to read it
Not the building's number and not the electricity meter: it is a tax number attached to your RIGHT, and it lives inside your Ε9.
Schematic example: find the property row and read its ATAK in column 1. This is not an image of an actual declaration.
What is the ΑΤΑΚ?
The ΑΤΑΚ (Αριθμός Ταυτότητας Ακινήτου) is the property identification number that the Greek tax authority (ΑΑΔΕ) assigns to each real-property right declared in the Ε9. On the Ε9 it is column 1 of Tables 1 and 2, filled in "if one has been granted": a property never declared in an Ε9 has no ΑΤΑΚ.
Where do I find my property's ΑΤΑΚ?
In your Ε9, inside myAADE. Log in at myaade.gov.gr with your TAXISnet codes and follow the path "Εφαρμογές" → "Φορολογικές Υπηρεσίες" → "Ακίνητα" → "Δήλωση Ε9/ΕΝΦΙΑ"; pick the year and, from the available actions, print your property status (περιουσιακή κατάσταση) or the submitted Ε9.
How many digits does the ΑΤΑΚ have, and what does it look like?
Between 9 and 11 digits — not always eleven. The ΑΑΔΕ manual gives the same number as 517728002, 0517728002 or 00517728002: leading zeros change nothing in the lookup.
Do you need the ΑΤΑΚ to file the lease declaration?
The short answer is no — and it is ΑΑΔΕ that says so, not us.
Do I need the ΑΤΑΚ to file the lease declaration in myAADE?
The field is optional — with one exception. The ΑΑΔΕ FAQ answers: "entering the Property Identification Number (Α.Τ.ΑΚ.) is optional and concerns properties that have been given such a number", and the user manual labels it "optional field".
The property is not in my Ε9 and has no ΑΤΑΚ — what do I do?
You can still file the lease declaration: the ΑΤΑΚ field is optional and only concerns properties that have already been given such a number, so leave it blank and type the address, floor and square metres by hand. The obligation that remains is a different one with its own deadline: the Ε9 property declaration for any creation, acquisition or change of a right is filed by 31 January of the following year — and, for inheritance, by the last working day of the month following the end of the renunciation period.
Why does the ΑΤΑΚ "not find" the property when I file the lease declaration?
Because the lookup runs against the Ε9 of the person filing, not against a general property register. The clearest documented case is sub-letting: ΑΑΔΕ instructs sub-lessors not to fill in the ΑΤΑΚ, "because the property will be searched for in the sub-lessor's Ε9, so a property-not-found message will be displayed".
- Lease signedthe day the lease starts
- Declared in myAADE by the landlordby the end of the following monthYou are here
- Accepted by the tenant30 days from the notification
- Proof of declaration (PDF)printed whenever needed: electricity, bank, housing benefit
- Ended or reneweddeclared by the end of the following month
ΑΤΑΚ and ΚΑΕΚ: two numbers, two authorities
They are confused because the same forms ask for both. They are not the same number in another shape.
ΑΤΑΚ vs ΚΑΕΚ — what is the difference?
They are two numbers issued by two different authorities: the ΑΤΑΚ is a tax number granted by ΑΑΔΕ inside the Property Registry, while the ΚΑΕΚ (National Cadastre Code Number) is a cadastral number granted by the Hellenic Cadastre. Their formats differ too: the ΑΤΑΚ is 9 to 11 digits, whereas the ΚΑΕΚ, as ΑΑΔΕ's own application describes it, has 12, 17 or 18 characters (digits and slashes) and may be provisional or final.
Can I find the ΚΑΕΚ from the ΑΤΑΚ (or the other way round)?
There is no public service that converts one number into the other; the two systems are separate and each is queried on its own. The place where they meet is the property's row in the Ε9: the ΑΤΑΚ in column 1 and the ΚΑΕΚ in column 27 sit on the same line, so if you ever filled the ΚΑΕΚ in, you read it there.
When there is more than one number
This is where «one ΑΤΑΚ per property» breaks: the number follows the right, not the walls.
Why does the same property have two (or more) ΑΤΑΚ numbers?
Because the ΑΤΑΚ follows the right, not the walls. ΑΑΔΕ states plainly that a dwelling "may consist of one or more ΑΤΑΚ", and the ΕΝΦΙΑ certificate is issued separately "for each ΑΤΑΚ", because it concerns the real right.
Do a storage room and a parking space have their own ΑΤΑΚ?
It depends on whether they hold their own share of the plot (χιλιοστά). ΑΑΔΕ puts it this way: auxiliary spaces with a share of the plot means that both the dwelling and the storage room have separate ΑΤΑΚ numbers and can therefore be declared separately — and in that case the storage room is declared among the main spaces.
What about the ΑΤΑΚ when the property is co-owned?
The lease declaration is filed by one of the co-owners, and the ΑΤΑΚ entered is that person's own — the one matching their right in their own Ε9. The other co-owners do not file again; they see the declaration and, if they disagree with its contents, they select "ΜΗ ΑΠΟΔΟΧΗ" (non-acceptance) stating the reasons, until the income-tax filing deadline.
What happens to the ΑΤΑΚ after a purchase, parental gift or inheritance?
The new holder sees the property — and its ΑΤΑΚ — in their own Ε9 only after the change is registered, and it is the transferor's ΑΤΑΚ that drives the process. When the notarial deed is uploaded to myPROPERTY, an Ε9 declaration is generated automatically for each party, and the descriptive fields are drawn from the ΑΤΑΚ of the transferred property in the seller's current property status.
Draw up the lease — with the ΑΤΑΚ or without it
Our free template keeps the ΑΤΑΚ optional, exactly as ΑΑΔΕ does. Fill in what you have; the agreement comes out ready to sign and ready for the declaration.
Where the ΑΤΑΚ is actually mandatory
Checked against the sources:
Lease declaration
Optional. It becomes mandatory only if you tick the clause allowing letting through a digital platform under article 111 of law 4446/2016.
ΑΑΔΕ lease FAQ (updated 4/9/2020), Q21 · article 111 of Law 4446/2016
Short-term stay registry
Mandatory: the Α.Μ.Α. is granted «after at least the ΑΤΑΚ of the property has been entered», and the number must correspond to a right other than bare ownership.
ΠΟΛ.1187/2017 (ΦΕΚ Β΄ 4232), articles 2–3
ΕΝΦΙΑ
As an output, not a field you fill in: the assessment notice carries one line per ΑΤΑΚ, and a separate ΕΝΦΙΑ certificate is issued for each ΑΤΑΚ.
Α.1061/2026, article 1 §5 · article 54Α of law 4987/2022
Sources
- ΑΑΔΕ — Έντυπο Ε9 «Δήλωση Στοιχείων Ακινήτων», οδηγίες συμπλήρωσης (Πίνακες 1 & 2, ΣΤΗΛΗ 1 και ΣΤΗΛΗ 27)
- ΑΑΔΕ — Δήλωση Ε9 / ΕΝΦΙΑ (ψηφιακή υπηρεσία, «Βήμα - βήμα», Πιστοποιητικό ΕΝΦΙΑ)
- Α.1099/2023 (ΦΕΚ Β' 4327/06.07.2023) — Αυτόματη δημιουργία και υποβολή ψηφιακής δήλωσης Ε9 μέσω myPROPERTY, άρθρα 2-3
- ΑΑΔΕ — Φορολογία Ακίνητης Περιουσίας (Ε9 - ΕΝΦΙΑ) για ομογενείς & κατοίκους εξωτερικού (διαδρομή στο myAADE)
- ΑΑΔΕ — Οδηγίες Χρήσης εφαρμογής «Δηλώσεις Πληροφοριακών Στοιχείων Μίσθωσης Ακίνητης Περιουσίας» (ενημ. 04-09-2020), σελ. 16-17
- ΑΑΔΕ — Μισθωτήρια Ακινήτων, Συχνές Ερωτήσεις-Απαντήσεις (Τελευταία Ενημέρωση 4/9/2020), ερ. 5, 21, 25, 33
- ΑΑΔΕ — Δηλώσεις μίσθωσης ακινήτων (Βήμα-βήμα, προθεσμίες)
- ΠΟΛ.1187/2017 (ΦΕΚ Β' 4232) — Μητρώο Ακινήτων Βραχυχρόνιας Διαμονής, άρθρα 2-3
- gov.gr — «Τα ακίνητά μου στο Κτηματολόγιο» (Ελληνικό Κτηματολόγιο, είσοδος με κωδικούς TAXISnet)
- Α.1014/2024 — Μείωση ΕΝΦΙΑ για ασφαλισμένες κατοικίες, άρθρα 1-3
- ΑΑΔΕ — Μισθωτήρια ακινήτων, Συχνές ερωτήσεις-απαντήσεις (παλαιότερη έκδοση, αντίγραφο taxheaven), ερ. 21
- ΑΑΔΕ — Έντυπο Ε2 «Αναλυτική κατάσταση για μισθώματα ακινήτων», έκδοση 2026 (φορ. έτος 2025)
- Α.1061/2026 — Τύπος και περιεχόμενο της δήλωσης ΕΝΦΙΑ - πράξης προσδιορισμού φόρου έτους 2026, άρθρο 1
Frequently asked questions about the ΑΤΑΚ
Where do I find my property's ΑΤΑΚ?
How many digits does the ΑΤΑΚ have?
Do I need the ΑΤΑΚ to declare a lease?
Why does one flat have two ΑΤΑΚ numbers?
What is the difference between ΑΤΑΚ and ΚΑΕΚ?
The property has no ΑΤΑΚ — can I still declare the lease?
We are not accountants or lawyers. This page states what the ΑΑΔΕ texts say, with the reference and the date we read them; for your own case ask your accountant.
What next? 3 steps — none of them required
mamaXO is a rental-management company in Athens. The tools are free; we earn only if one day you hand us the flat.
Keep it in a free account
The contract stored, your ΑΑΔΕ deadline worked out, documents in one place. No time limit, no card.
Find a tenant — list it free
A live listing on mamaXO with 3 photos; you run the viewings yourself. Free, for as many flats as you have.
Or hand it all to us — Autopilot, 10% + VAT
Tenant search and checks, contract, ΑΑΔΕ filing, rent collection, repairs, a monthly statement — all by us. Only on rent that arrived; nothing while the flat is empty.
The decisions stay yours, as you set them in the mandate.
What we do
We manage lettings in Athens: we find the tenant, sign the agreement, file the declaration with ΑΑΔΕ and collect the rent. The free lease template is the one we use ourselves.
Send this to whoever is hunting for their ΑΤΑΚ