myDATA is the online platform of AADE (the Greek tax authority) where business income and expenses are recorded. For an e-shop this simply means: every sale needs a tax document (receipt or invoice), and that document must reach myDATA.
This guide is practical, not tax advice. Your accountant settles the details of your own case.
Three ways to do it
1. Manually, from your accountant's software
For every order you issue a receipt or invoice in separate software. It works for a few orders a month, but it takes time and increases mistakes.
2. Connecting the e-shop to an e-invoicing provider
The e-shop automatically sends the details of each order to a certified provider, which issues the document and transmits it to myDATA. The customer gets the receipt by email. This is the solution we recommend for most e-shops.
3. Connecting to business management software (ERP)
If you already use an ERP for stock and accounting, orders go there and the ERP issues the documents. It suits larger businesses or anyone who also has a physical store.
What needs to be set up in the e-shop
- Receipt or invoice: the customer chooses at checkout, and if they want an invoice they fill in their VAT number and company details.
- Correct VAT per product: not all products have the same rate.
- Shipping and cash on delivery fees as separate lines on the document.
- Cancellations and returns: a credit note when a paid order is cancelled.
Common mistakes
- The e-shop opens before agreeing with the accountant which software will be used.
- Documents are issued only for card payments, and cash on delivery orders are forgotten.
- A product's VAT rate changes and is not corrected in the e-shop.
How much it costs
E-invoicing providers usually charge a small monthly subscription based on the volume of documents. Connecting the e-shop is a one-off job. In the e-shops we build, the myDATA connection is optional and works with whichever provider or software your accountant already uses.
See also the full guide on what you need to open an e-shop: tax office, KAD (business activity code), payments and couriers.
