The Estonian Tax and Customs Board (MTA) is introducing one of the most significant changes to companies reporting obligations in recent years — data-based reporting. We want to give you an overview of what this means, when it takes effect, what specifically changes in the data, and why this will also require changes to the accounting/ERP software of many companies.
What is data-based reporting?
This is part of a national real-time economy initiative, led by the Ministry of Economic Affairs and Communications in cooperation with the MTA. The goal is simple: to enable companies to fulfil their tax and reporting obligations directly from their accounting software, without having to log into the separate e-MTA environment and enter data manually. Declarations will be compiled automatically based on the submitted underlying data, and the data will be transmitted in machine-readable format. According to the MTA’s estimates, this could save Estonian companies more than 4 million working hours.
More details are available on the MTA website: Data-based reporting | Estonian Tax and Customs Board.
When does it take effect, and what does it cover?
The change will take effect in phases:
- October 2026 — TSD Annexes 1 and 2. The submission of payroll data will move to the data-based format. The deadline for submitting October payroll payments under the new format is 10 November 2026. Files in the old XML format can no longer be uploaded.
- April 2027 — the submission of VAT return (KMD) and Employment Register (TÖR) data will also become data-based.
- 2027–2028 — the remaining TSD annexes (3–7) will be added to the transition in phases.
The change affects all businesses that submit TSD, KMD, or TÖR data — in practice, virtually all employers and VAT-liable entities.
What exactly changes for the TSD?
TSD Annexes 1 and 2 cover payroll and other payment data, together with the associated income tax, social tax, unemployment insurance contributions, and mandatory pension contributions. Currently, a company prepares a consolidated declaration by the 10th of each month — essentially totals aggregated over the month by payment type, often checked manually in Excel or on the declaration form. Under the data-based model, the logic changes in several respects:
- Transaction-level reporting: data will be transmitted to the MTA on a transaction basis, and the level of detail will generally remain consistent with current practice. It is important that each transaction or operation is additionally tagged using the values of the new MTA classifiers (including the type of VAT-related transaction or operation; the identifier of the transaction counterparty or invoice). This also means that intra-Community supply data will no longer be requested separately by the MTA in a duplicative manner going forward. Data will be submitted at line-item level within the KMD data structure.
- New file format: via the machine-to-machine interface, data can only be submitted using the new XML format based on the XBRL GL standard. When uploading via the user interface, either the XBRL GL or CSV format can be used. It is important to note that, in connection with the new technical solution, from the April 2027 tax period onward, data uploads will be supported only in the XML or CSV format based on the new taxonomy.
What exactly changes for the TÖR (Employment Register)?
The submission of Employment Register (TÖR) data will likewise move away from manual registration in e-MTA — the goal is for changes relating to the start, end, and other details of an employment relationship to flow directly from HR/payroll software to the MTA in machine-readable form, following logic similar to that of the TSD and KMD. This means that HR data (type of employment relationship, workload, position, etc.) must also be available in the software in structured form from the moment the change in the employment relationship is made, rather than only at the time the report is compiled.
What does this require from your accounting/ERP software?
It is important to understand that this is not merely a cosmetic change to the file format — it represents a substantial development effort on the part of software providers, which will inevitably affect end users as well:
- Software needs to be built to support the XBRL GL standard (an XML-based international standard for exchanging business transaction data) — this will replace the current, simpler XML upload logic.
- Machine-to-machine interfaces (e.g. via the X-Road) need to be updated to provide a direct connection to the MTA’s information system, rather than merely supporting file uploads.
- The software’s chart of accounts and transaction(-type) classifiers need to be mapped to the new codes (e.g. KMD reporting codes, TSD payment types).
In practice, this means that some companies will need to account for both a software update (and a possible additional cost from their software provider) and a review of their internal processes — including their chart of accounts and data-entry practices.
OIXIO has already begun development work
We are pleased to confirm that OIXIO has already launched development work related to support for data-based reporting and is tracking well against the timeline published by the MTA. Our goal is to ensure that our clients can put the new solution into use on time, in line with the relevant declaration submission deadlines.
What does this mean for you?
The most important question, of course, is what this specifically means for your company — and that depends primarily on the software you use, its version, and the additional features currently in use. For some clients, the transition will largely be a smooth and seamless change within their existing solution. For others, moving to data-based reporting may require additional development costs or a greater workload if their current software does not support data-based reporting.
So that you don’t have to work this out on your own, we recommend contacting your client relationship manager today — together, we will review exactly what the change means for your company, whether and what kind of update it requires, and how to get everything done smoothly and on time. If you have any questions, or would simply like more information, please don’t hesitate to get in touch — we’re happy to help!