myDATA is the electronic books platform of AADE, the Greek Independent Authority for Public Revenue. Business software sends it the data of each invoice issued, as InvoicesDoc XML through a REST API, and myDATA answers with a unique registration number, the MARK. Classifications follow. The current API is version 2.0.2. myDATA data is not the e-invoice itself. Klarbon plans to open myDATA XML; this is not available yet.
What does myDATA carry?
| API call | What it does |
|---|---|
SendInvoices |
sends one or more invoices, including corrections, in an InvoicesDoc |
SendIncomeClassification |
classifies income on invoices already sent |
SendExpensesClassification |
classifies expenses on invoices received |
SendPaymentsMethod |
adds payment methods to invoices already sent |
CancelInvoice |
cancels an invoice without sending a new one |
RequestDocs |
fetches documents that others have sent about the business |
RequestTransmittedDocs |
fetches documents the business has sent |
| Property | Value |
|---|---|
| Authority | AADE, the Independent Authority for Public Revenue |
| Current version | 2.0.2, September 2026, with an XSD package |
| Format | XML over HTTPS, with user identification in each call |
| Identifier | MARK, the unique registration number of each document |
AADE's technical description lists the calls, the XML and the technical requirements (AADE API description). The versions page publishes the XSDs, separate specifications for e-invoicing providers and for digital goods movement documents, and the changes in each release (AADE versions).
myDATA and Greek e-invoicing
| myDATA report | Greek e-invoice | |
|---|---|---|
| What it is | tax data about a document | the invoice itself |
| Issued through | business software, a provider or AADE forms | a certified provider or timologio |
| For public buyers | MARK on the invoice | Greek Peppol BIS through Peppol |
According to AADE, e-invoicing is mandatory from 2 March 2026 for businesses with gross revenue above 1,000,000 euros in tax year 2023, and from 2 November 2026 for the rest, with a gradual transition until 31 January 2027 (AADE FAQ).
What does Klarbon do with myDATA?
Opening myDATA XML is planned, not available yet. Klarbon does not report to AADE or issue MARK numbers. It opens Peppol BIS invoices; see the invoice viewer.
Related
Frequently asked questions
What is myDATA?
myDATA, my Digital Accounting and Tax Application, is the electronic books platform of AADE, the Greek Independent Authority for Public Revenue. Businesses send it the data of the invoices they issue and the classification of their income and expenses.
What is a MARK number?
The unique registration number that myDATA gives each document it accepts. Greek e-invoices carry it, and later calls, such as classifications or a cancellation, refer to it.
Is a myDATA XML an e-invoice?
No. The InvoicesDoc XML is the data a business reports to AADE. The e-invoice itself is issued through a certified provider or AADE's free timologio application, which also send its data to myDATA.
When did e-invoicing become mandatory in Greece?
For businesses with gross revenue above 1,000,000 euros in tax year 2023, from 2 March 2026. For all others, from 2 November 2026, with a gradual transition until 31 January 2027 for businesses that declared it in time.