What an ERP is, and when a small business in Greece needs one.

ERP stands for Enterprise Resource Planning. It is the software where everything a business does is recorded: what it sold and to whom, what it bought, what’s in the warehouse, what it owes and what it’s owed.

A note on words: in Greece hardly anyone says ERP. Your Greek colleagues and your accountant will usually call it the εμπορικό πρόγραμμα (literally “the commercial program”) or the πρόγραμμα αποθήκης και τιμολόγησης (“the warehouse and invoicing program”). They mean the same thing.

The difference from Excel or from a simple invoicing program is that all of this is tied together. Take an order. It goes in once, and the stock is reserved. The invoice is issued from the order, without being typed again. The warehouse sees what to prepare, and the customer’s balance updates by itself.

In practice, nobody in the office types the same data twice. And when you ask “how many of these do we have?”, everyone sees the same number.

An ERP has parts, and you don’t need all of them from day one. These are the usual ones:

Part	What it does	Who uses it
Sales	Quotes, orders, price lists per customer	Sales team, office
Customers (CRM)	History, contacts and next steps with each customer	Sales team
Purchasing	Orders to suppliers, goods received, purchase invoices	Office, warehouse
Inventory	Stock per warehouse, moves, delivery notes, stock counts	Warehouse
Invoicing	Invoices, receipts and credit notes, through a provider	Office
Accounting	Payments, bank, balances, reports for the accountant	Accounts team or your accountant
Payroll	Salaries, payslips, data for ERGANI (the Greek labour ministry’s system)	Accounts team or your accountant
eshop	The site that sells, with prices and stock from the ERP	Your customers

You usually start with sales, inventory and invoicing, and add the rest when you need it.

Excel is a very good tool for a business that is starting out. At some point, though, it starts to cost hours, and mistakes you pay for. If you recognise three or more of the following, it’s time:

• You type the same data two or three times. The order goes into Excel, then into the invoicing program, then into the courier’s website.
• Only the warehouse knows the stock for sure. To answer a customer, you phone downstairs.
• The eshop shows something as available that has run out, and you cancel orders by phone.
• Prices sit in a file that one person updates. When they’re away, nobody is sure which price applies.
• There are many Excel files, and none agrees with the others. Or there’s one that nobody can make sense of any more.
• Closing the month with the accountant takes days, because invoices, payments and the bank are in different places.
• You don’t know which products make you a profit, because purchases and sales are never in the same table.

Three kinds of software are often confused, because they all have sales and invoices in them.

• Your accountant’s software keeps the books, the VAT and the tax returns. It doesn’t know what’s in your warehouse or which order is waiting to go out.
• The eshop sells. It knows its own orders, but not the shop’s sales, the orders taken by phone or what came in from the supplier today.
• The ERP sits in the middle. Every sale and purchase is recorded there, wherever it comes from, and the eshop and your accountant take their data from it.

AADE’s timologio, the free invoicing app of the Greek tax authority, is something else again: you type each invoice by hand. It doesn’t keep stock, orders or customers with a history.

An ERP doesn’t take only money. It takes time from your team too, and it’s worth working that out beforehand. As a guide, for a first phase with sales, inventory and invoicing, as we set it up in Odoo:

Stage	What you do	When
Mapping	You show us how you work: orders, prices, warehouse, invoices	Weeks 1–2
Cleaning up the data	You check codes, prices and customers before they’re moved	Alongside the setup
Setup	You answer questions and see the first screens	Weeks 3–6
Testing	Your team and your accountant test with real examples	Week 7
Go-live	You work in the new system, with us beside you	Week 8 and the first weeks after

The heaviest part is almost always the data. Codes entered twice, customers without a VAT number, prices in three files: whatever goes into the new system wrong, you’ll keep running into for years. From the start, name one person on your team who knows the products and will have a few hours a week for it.

The first weeks are slower. The team is learning new screens, and some things take an extra click until they become habit. That’s why we avoid starting in the busiest month of your year.

Your accountant is involved from the start. They say what data they need from the system, and they check the first invoices before go-live.

The ERP and the eshop share the work. Usually the ERP has the last word on products, prices, stock and customers, and sends them to the eshop. The eshop has the last word on orders, and sends them to the ERP within seconds.

So an eshop order isn’t typed again in the office, and the stock on the eshop and the marketplaces is what’s on the shelf. See how we set up eshop–ERP integration, and which system decides for each kind of data in the guide which system has the last word.

From 1 February 2027, businesses that issue invoices from an ERP or an eshop must send them through a licensed provider, or else issue them by hand in AADE’s free apps. An e-invoicing provider is a company licensed by AADE that signs your invoices and sends them to myDATA, the tax authority’s platform.

In practice, you issue the invoice in your ERP as always. The software sends it to the provider and the provider to myDATA, and the MARK (the number AADE gives the invoice) comes back with the QR code and is printed on it. If the connection drops, the invoice isn’t lost: it waits and is sent again as soon as the connection is back.

So when you choose an ERP, ask how it connects to a provider. You’ll find more on the page about Greek e-invoicing through a provider and in the guide to choosing an e-invoicing provider.

Whichever ERP you look at, five questions quickly pick out the one that will serve you for years:

1. Does it do what Greek law requires? The right document types for myDATA, a connection to a provider, digital delivery notes, and payroll if you want it inside the system.
2. Does it connect to the eshop and the marketplaces? With a ready-made connection or through an API, and who maintains it.
3. Can I start with one part? For example sales and inventory first, and the rest later.
4. Where does it run, and who keeps the backups? And what happens if you want to move it elsewhere.
5. Who owns the data? The answer must be “you”, with a way to take all of it whenever you like.

Not every business needs an ERP. If you issue a few invoices a month, hold no stock and have no eshop, AADE’s free apps, timologio and myDATAapp, together with your accountant, are enough.

The same goes if you already have an ERP that serves you well. For 1 February 2027 it’s enough to connect it to a provider, and a move to other software can wait. See the guide keep your ERP now, Odoo later.

1. Write down how you work today: where orders come from, where the prices are kept, where invoices are issued from.
2. Note where you lose time: which data you type twice, and which mistakes keep coming back.
3. Talk to your accountant: what data they need from you, and in what form.
4. Start with the part that costs you most, not with everything at once. Usually that’s orders and stock.

We set up Odoo for companies in Greece, with the Greek add-ons for myDATA, delivery notes and payroll. If you’re considering it, see which edition suits you in the guide Odoo Community or Enterprise.