Integration Guide - Oxygen Accounting (myDATA)

For car rental businesses in Greece, staying compliant with the country’s electronic invoicing and reporting regulations — especially the myDATA government system — is critical. With RentSyst’s new integration with Oxygen Accounting, managing financial reporting becomes easier, faster, and fully automated.

The documents you issue through the Oxygen application are certified. Application is a Licensed Electronic Invoicing application by the A.A.D.E., and supports the issuance of certified documents, in accordance with applicable laws and regulations.

In this article, we’ll guide you step by step through integrating RentSyst with Oxygen, and explain how this integration supports Greek businesses with seamless reporting directly to the Independent Authority for Public Revenue (AADE).

Why Integrate RentSyst with Oxygen?

Oxygen is a powerful online accounting platform widely used by businesses across Greece. It provides:

• Real-time invoice management
• Direct communication with the myDATA platform
• Tools for accountants and business owners to automate compliance
• Cloud-based access for secure and flexible usage

By integrating RentSyst with Oxygen, car rental companies can:

• Automatically sync invoices and customer data
• Ensure every transaction is correctly reported to myDATA
• Reduce human error and save time on manual submissions
• Stay fully compliant with Greek tax regulations
• Offer transparency for auditors and accountants

INTEGRATION GUIDE:

Step 1: Activate Your Oxygen Account

If you haven’t already, create an Oxygen (Pelatologio) account. Choose the appropriate plan based on your business needs.

Step 2: Log in to RentSyst

Go to your RentSyst admin panel and navigate to the Integrations section.

Step 3: Enable Oxygen Integration

Find "Oxygen Accounting" in the integrations list and click Activate.

You’ll be prompted to enter your Oxygen API key. You can request it in your Oxygen support manager:

you will need to send a message through the application's internal messaging system so that Oxygen Team can generate it and send it to you directly.

Press “Connect”.

Step 4: Configure Data Sync

Choose data categories for synchronization:

• Taxes
• Rental
• Delivery
• Penalties
• Equipment
• Insurance
• Payment method

Activate checkbox “Send Invoice” and select start delivery date for Invoices (records).

Make sure your tax profiles in RentSyst match the required format for myDATA reporting. It should be a 24% tax rate.

Step 5: Mapping

Now it's time to connect RentSyst units with Oxygen units entities.

On the left side = Rentsyst units.

On the right side = Oxygen units.

You need to connect the same products here.

If you do it first time – the best & fastest way is using RentSyst automation called “Create new service”. It will automatically create a product list with the same Rentsyst entities in your Oxygen account.

If you want to make it manually, you may create your product list on the Oxygen side, follow the Warehouse - Products > Categories & Variations tab.

Here is a sample how complete mapping should looks like – all product should be linked:

Delivery category

Penalties category

Equipment category

Insurance сategory

Payment method category

By clicking the SAVE button, Oxygen integration is completed!

Step 6: Integration logic

6.1. All set. Oxygen Accounting has been successfully integrated into RentSyst!

Now your Invoices will be sended to Oxygen automatically after the status of the order is changed to "Done".

You will see Oxygen icon nearby the reservation:

• - if Oxygen logo is highlighted grey - means Invoice was not sended
• - if Oxygen logo is highlighted green - means Invoice was successfully sended into your Oxygen account

6.2. You may also send request to integrate Invoice manually directly from Rentsyst now.
Simply press on grey icon, the system will double check if you wanna upload Invoice to your Oxygen Accounting.

6.3. And finally,
you can also open Invoice on your Oxygen side directly from Rentsyst as well.

Special benefits for Greek car rental business

The integration is designed with the Greek market in mind, offering:

• Full myDATA compliance
• Automatic e-invoice generation
• Smooth collaboration with Greek accountants
• Less paperwork, more automation

Whether you're managing a small car rental agency or a multi-location fleet, this integration simplifies your accounting process and keeps your business in line with local legal requirements.

Final thoughts

RentSyst continues to support car rental businesses with tools that save time, reduce errors, and ensure full compliance. The integration with Oxygen Accounting is a game changer for Greek rental operators looking to modernize their workflows and meet tax requirements without hassle.

Ready to integrate? Reach out to the Support team or follow the steps above to get started today!

Contact to Rentsyst support

Contact to Oxygen support