Web interface, XML upload or M2M: which eVAT channel suits you?

How to decide

For companies

For a company, the channel decision shapes the filing process for years. For many mid-sized and larger businesses, M2M is the more practical option, particularly for the following four reasons:

Workload: on the web interface, NAV’s draft has to be checked item by item every period, tax codes overridden and missing documents recorded. With M2M, the tax records are generated by your own system.

Complexity: the more cross-border, reverse-charge or specially coded transactions you have, the less you can rely on the data NAV already holds.

Corrections: for returns filed over the machine interface, a self-revision within 15 days is surcharge-free.

Reliable taxpayers: NAV may not audit a return filed over the machine interface for 15 days from the due date.

The M2M connection does not have to be developed in-house. Filing software can combine connectivity, validation of VAT records, NAV feedback and submission in a single workflow.

For accounting firms

For an accounting firm, the question is how much of the client portfolio should move to M2M. The more clients run in the same process, the more predictable the 20 January deadline becomes.

M2M: clients with higher volumes, complex transactions, frequent self-revisions or an ERP. For them, the surcharge-free self-revision is a direct benefit, and the return is produced from the accounting data without work on the interface.

Web interface: low-volume clients with simple domestic transactions. Bear in mind that only the client or its permanent representative can approve the draft — a secondary user cannot.

XML upload: suitable as an interim solution where the accounting software produces eVAT XML, but the process stays on the interface every period.

The more channels a firm runs in parallel, the more different processes it has to operate for the same deadline. SimplyX handles the M2M submissions of multiple clients in one interface, in a single workflow. How SimplyX eVAT M2M works

Which eVAT channel suits you?

Six questions based on the legal conditions and practical considerations. Accounting firms: answer with one specific client in mind — you can run it again for each client.

1. Where does the return data come from?
   • Mainly from invoice and receipt data NAV already holds — On the web interface, NAV compiles an automatically tax-coded draft from this data. It has to be checked item by item, amended where needed and approved every period.
   • From accounting software that can generate eVAT XML — XML upload replaces data entry on the interface. Validate the file against the schema before uploading, because supplementary sheet data cannot be added on the interface afterwards. (eVAT XML checker)
   • From an ERP or several source systems — With several source systems, the machine-to-machine connection has the fewest hand-over points: the tax records go to NAV straight from the company’s systems. (How SimplyX eVAT M2M works)
2. What are your transactions typically like?
   • Simple, domestic transactions
   • Mostly domestic, with some more complex ones — For more complex transactions, NAV’s automatic tax coding has to be overridden in several places. On the web interface this has to be redone every period.
   • Regularly complex transactions (cross-border, reverse charge, special tax codes) — NAV considers the web interface most suitable for taxpayers with non-complex domestic transactions. For complex transactions, tax records generated by your own system are the more reliable basis.
3. How many invoices are there in a return period?
   • A few hundred
   • Several thousand or tens of thousands — At this volume, reviewing the draft and recording corrections on the web interface is substantial work every period.
   • 100,000 or more — The web interface can be used with fewer than 100,000 invoices per return period, so at this volume the options are the M2M connection or XML upload. (NAV guidance (in Hungarian))
4. How often do you file self-revisions?
   • Rarely
   • A few times a year
   • Regularly — For a VAT return filed over the machine interface, no self-revision surcharge is charged if the self-revision is filed within 15 days of submission, but no later than 15 days after the due date (Art. 211 (3) c)). (Act on the Rules of Taxation (in Hungarian))
5. Does the company hold “reliable taxpayer” status?
   • No
   • Yes — Among the benefits of reliable taxpayers: NAV may not audit a VAT return filed over the machine interface for 15 days from the due date — unless there are well-founded grounds to suspect concealed income or false documents (Art. 154 (5)–(6)).
6. Do you have the capacity or software to run an M2M connection?
   • No — The M2M connection does not have to be built in-house: filing software built on it provides the technical connection, validation and feedback handling ready to use. (SimplyX eVAT M2M)
   • Partly
   • Yes

• Web interface: The web interface may be enough — as a conscious trade-off. With low volumes and simple domestic transactions, checking and approving the draft compiled by NAV works. Bear in mind, though, that it requires manual steps every period, and the benefits tied to the M2M connection do not apply. The eVAT web interface (NAV, in Hungarian) · What M2M adds
• XML upload or M2M: You have structured data — M2M is closer than you think. XML upload gets your own data to NAV, but the process stays on the interface every period. If you already generate the file, the M2M connection is a smaller step than it seems — and only M2M comes with the surcharge-free self-revision. SimplyX eVAT M2M · eVAT XML checker
• M2M connection: The M2M connection gives you the most. Based on your data sources, transaction complexity or the frequency of self-revisions, the machine-to-machine connection is the best-suited channel: the law ties the surcharge-free self-revision and the 15-day audit protection for reliable taxpayers to it. Start preparing now — registration, tax-code mapping, testing. Request a SimplyX consultation or trial · eVAT M2M registration

Which channel, in which situation?

Pick the answer you think is right. The explanation appears after you choose.

1. For companies: A mid-sized trading company handles around 8,000 invoices per return period. The data comes from an invoicing system and an ERP, and it regularly buys from abroad. Which channel makes most sense?
   • The web interface — It can be used, but NAV’s draft has to be reviewed item by item every period, the tax codes of cross-border purchases overridden, and the data of the two source systems reconciled on the interface. At this volume that is substantial, recurring work.
   • Correct: M2M connection — Correct. With two source systems and complex transactions, the M2M connection has the fewest hand-over points, and the legal benefits are tied to it. The tax records are produced directly from the company’s data.
   • XML upload — It works if the system generates eVAT XML. However, the law ties the surcharge-free self-revision and the reliable-taxpayer audit protection to returns filed over the machine interface.
   Source: NAV: the eVAT web interface (in Hungarian)
2. For accounting firms: One of the firm’s clients is a small service company: domestic transactions only, 60–80 invoices per return period. Which channel makes most sense?
   • Correct: The web interface — For this client alone, the web interface is enough: NAV considers it most suitable for taxpayers with non-complex domestic transactions. But if most of the firm’s clients need M2M, it is simpler to run this client in the same process too.
   • XML upload — Possible, but with so few invoices, generating and checking your own XML is more work than reviewing NAV’s draft.
   • M2M connection — Building a separate connection for one such client is not worth it. It is different if the firm handles its clients on a shared platform built on M2M — then this client can be added with little extra work.
   Source: NAV: the eVAT web interface (in Hungarian)
3. For accounting firms: A member of the firm’s staff works on a client’s eVAT web interface as a secondary user. Can they approve the draft return?
   • Yes, if they made the amendments — No. A secondary user may amend and supplement the data, but their rights do not extend to approving the draft as the return.
   • Correct: No: only the taxpayer or its permanent representative can approve — Correct. The web interface is accessed as primary user by the taxpayer or its permanent representative, with electronic identification. A secondary user can amend and supplement, but not approve. With many clients, this has to be factored into the January schedule.
   • Yes, a secondary user has full rights — No. Their rights cover amendments and additions, not approval.
   Source: NAV: eVAT — a new way to file VAT returns (in Hungarian)
4. For companies: A manufacturer keeps its books in an ERP and files several corrections and self-revisions every month. What speaks most for M2M?
   • Self-revisions can only be filed over M2M — No. A return filed on the web interface can also be corrected by self-revision on the electronic interface. The difference is the surcharge.
   • Tax codes cannot be changed on the web interface — No. On the web interface the automatically assigned tax code can be changed — it is just work done on the interface every period.
   • Correct: The surcharge-free self-revision — Correct. For a VAT return filed over the machine interface, no self-revision surcharge is charged if the self-revision is filed within 15 days of submission, but no later than 15 days after the due date (Art. 211 (3) c)). With frequent corrections, that is a direct saving.
   Source: Art. 211 (3) c) — National Legislation Database (in Hungarian)
5. You send the December tax records over M2M. What feedback does the system give, and when?
   • All check results arrive immediately, on upload — No. Only the technical result of the upload steps arrives immediately; content validation runs asynchronously after finalisation.
   • A return with warnings cannot be submitted — No. Only ERROR-level issues block submission. Warnings do not, but their content has to be reviewed.
   • Correct: Processing decides whether it can be submitted; long-running checks may come later — Correct. After finalisation, processing ends in FINISHED (can be submitted) or ABORTED (has errors, must be corrected). Long-running checks may continue afterwards: they are not a precondition for submission, but a useful signal. According to NAV, full validation can take 3–5 days — if you want to see all feedback before submitting, upload earlier.
   Source: eVAT M2M 2.0 interface specification, pp. 135–139 and 167