# From 1 October, B2B e-invoicing is mandatory for the rest of Greek business > From 1 October 2026 remaining Greek businesses must issue B2B e-invoices. What a licensed provider, timologio, ERP, and POS mean in practice, not in a circular. - Canonical HTML: https://fossasoft.com/blog/mandatory-b2b-e-invoicing-greece/ - Markdown: https://fossasoft.com/llms/en/blog/mandatory-b2b-e-invoicing-greece.md - Language: en-GB Fossasoft, Ioannou Metaxa 34, Leptokarya 60063, Greece. Phone +30 2352 031 337. Email info@fossasoft.com. Monday–Friday 09:00–21:00. VAT EL164317738. GEMI 165469048000. Map: https://g.co/kgs/6Lt2hQB If you sell to other businesses in Greece, the invoice has to become an electronic invoice. Not a Word file, not a scanned PDF, not “we will type it into myDATA later”. Decision A.1128/2025 sets the timetable. The second wave starts on 1 October 2026 . Fossasoft is a software studio at Ioannou Metaxa 34 in Leptokarya. We are not a licensed e-invoicing provider. We set up invoicing, ERP, and POS, and we connect them to a provider you actually declare. This note is the operational version: what the rule is, where the free AADE apps stop, and why a till that cannot talk to a provider will hurt you in October. The obligation covers B2B sales of goods and services in Greece, B2B with countries outside the EU, and B2G where a more specific public-procurement rule does not already apply. AADE has also said this mandate does not change how you issue retail receipts to final consumers. Retail stays retail. Wholesale invoices are the job. You fulfil it through a licensed provider of electronic document issuance (πάροχος), as an exceptionally large self-provider, or through AADE’s free timologio and myDATAapp . Those three are not equal on a shop floor. timologio issues and transmits. It does not run your catalogue, your till, or your warehouse. The split is gross revenue on the 2023 income-tax return, not how busy you feel this summer. Do not guess the bucket from a bank balance. The 2023 return is the document. If you started later than 2023, still treat 1 October as the working date until your accountant says otherwise. The AADE myDATA hub is the official place, not a Facebook summary. The law does not say “every business must buy a provider”. It says issued electronic invoices. AADE’s free apps are a real option for a tiny volume of B2B documents typed by hand. The moment you have a POS, an item file, and customers who buy on account, typing each invoice into timologio is how you miss the afternoon queue. A licensed provider is the party AADE recognises to issue and authenticate the document. You sign with them. They appear on AADE’s provider list. Fossasoft connects your software to that provider. If someone sells you “myDATA” without a provider contract and you are not living inside timologio, ask what authenticates the invoice. That is the part owners mix up in Pieria as much as in Athens: myDATA is the platform where data arrives. The provider is how a commercial invoice becomes an electronic invoice in the first place. Connecting POS to myDATA with no issuer in the middle is not a plan. Retail receipts and B2B invoices often sit in the same building. A hotel breakfast till and a company invoice for a coach group. A shop that sells over the counter and also supplies other shops. If those are two programs, staff will invoice from memory after closing. That is the failure mode October punishes. The stack that survives is boring: items and customers in ERP, the till using the same items, B2B documents issued from that file, authentication through the provider, arrival in myDATA. We describe that job on invoicing, ERP and POS . Hospitality operators who already look at Resty should know the product talks to a provider for receipts, it still does not replace a wholesale invoicing setup. Sit with the 2023 return and your accountant. Write down how many B2B invoices you issue in a busy month, which program prints them, and whether the POS catalogue is the same file. Bring that to a conversation with us if the software side is the gap. Bring it to the accountant if you still do not know whether you are in the February group or the October group. Office hours are Monday–Friday, 09:00–21:00, at Ioannou Metaxa 34, Leptokarya 60063. The Maps pin is the same address as the invoice. For the till itself see POS software . For the connection job see invoicing and ERP . ## FAQ **Do I legally have to have a πάροχος for B2B invoices?** You legally have to issue electronic B2B invoices. A licensed provider is the practical way if you run ERP or POS. AADE’s timologio and myDATAapp remain a legal alternative for low-volume, typed documents. They are not a till system. **Does this apply to receipts I give customers at the counter?** AADE has said the e-invoicing mandate does not change how you issue retail receipts to final consumers. B2B invoices are the change. If the same POS also needs to issue wholesale invoices, the systems still have to connect. **Is Fossasoft a licensed e-invoicing provider?** No. We set up invoicing, ERP, and POS software and connect them to a licensed provider you contract with. Your accountant should be in that conversation. **When is the date for a small business in Pieria?** If 2023 gross revenue was €1 million or less, treat 1 October 2026 as the start. If it was above, you were already in from 2 February 2026. Confirm on the 2023 return, not from memory. ## Contact - https://fossasoft.com/contact/ - info@fossasoft.com - +30 2352 031 337 - https://fossasoft.com/company/