ePostman
for mandatory e-invoicing
Send and receive electronic invoices over the Peppol network — with automatic reporting to the Slovak Financial Administration, 5-level validation and optional archiving for up to 10 years. A certified “digitálny poštár” by SLOVAKODATA.
MINI plan free up to 5 invoices a month · No credit card · Sign in at postman.slovakodata.com
Registration starts on the Financial Administration portal
Choosing a certified delivery provider is a mandatory step on the Slovak FA portal. Pick SLOVAKODATA, we receive your verified company data, send you an activation invitation and you finish onboarding with us in minutes.
What happens after you click
- On the FA portal you sign in via Slovensko.sk and confirm the pre-selected SLOVAKODATA.
- The Financial Administration sends us your verified company data.
- You get an “Activate your account” e-mail — the link is valid for 7 days.
- On one page you add your company ID, contact, password and consents. Done.
Everything for your e-invoicing
From invoice delivery to tax authority reporting — one application, portal and API
Sending and receiving via Peppol
Delivery over the secure AS4 protocol. For every invoice we keep a cryptographically signed transport receipt and the business MLS acknowledgement from the receiver’s Access Point.
5-level validation
Every document is checked against XML, UBL, EN 16931, Peppol rules and the Slovak national rules — exactly as the legislation and the Peppol network require.
Tax authority reporting
The tax data report (TDD) is derived automatically from your invoice and sent to the Financial Administration in parallel with delivery. Data leaves within the statutory deadline with no manual work.
Web inbox
Received and sent invoices in one place — PDF preview, status history, full-text search including Peppol IDs, CSV export and e-mail notifications.
API for your ERP
REST API and the standardised SAPI-SK interface with a public OpenAPI specification. Webhooks notify you of every status change — invoices flow straight from your accounting system.
Secure archive for up to 10 years
The original XML and a human-readable copy with optional archiving for up to 10 years. An auditable delivery trail — receipts and statuses for every document.
Validation API for testing documents — before you send for real
Every provider validates invoices because the law requires it. On top of that, we give you a validation API to test your ERP exports during preparation — no invoice is created, no credit is consumed, and findings include the exact location of each issue. One more call tells you whether your customer is already registered in the Peppol network.
Submitting an invoice in the portalPaste a ready-made XML document into the portal with no integration at all.
Take the UBL invoice generated by your accounting system, paste it into the portal, pick the receiver, and we validate and deliver it. The ideal start before connecting your ERP via the API.
Sending from your ERP via APIInvoices leave straight from your accounting system via REST or SAPI-SK.
Submission in a single call with replay protection (Idempotency-Key). SAPI-SK is the standardised Slovak interface, so the integration carries over between providers.
API documentation →Delivery via Peppol (AS4)Documents travel encrypted and signed over the Peppol network protocol.
AS4 transport signed with a Peppol certificate. The receiver is discovered automatically through an SMP lookup in the network.
Receipts for every invoiceA transport receipt plus the business MLS acknowledgement from the receiver’s provider.
We keep the signed AS4 receipt and the MLS acknowledgement — proof that the receiver’s Access Point took the document and accepted it. Both are visible in the invoice detail and via the API.
Receiver check before sendingBefore every dispatch we verify the receiver can actually accept the document.
An automatic SMP lookup confirms the receiver is in the network and supports the document type. If not, the invoice stops with a clear error instead of getting lost.
Duplicate controlThe same document cannot be submitted twice by mistake.
A business key per the Financial Administration methodology (supplier, type, invoice number, date) blocks duplicates on the portal and API alike, while an honest retry after an outage still goes through.
Automatic delivery retriesAn outage on the receiver’s side is handled for you.
Failed deliveries are retried with growing back-off. You learn the final outcome through a notification and the document status.
Receiver outside PeppolA document for an unregistered receiver does not get stuck.
The domestic substitute flow per the FA methodology: the tax report still goes out and you deliver the document by an agreed channel — with a “Delivered outside Peppol” status.
Status history timelineThe document’s whole life from submission to acceptance on one axis.
The History tab shows every step with a timestamp: Pending, Validated, Sent, Delivered, Accepted — including any errors along the way.
Web inbox for received invoicesAll incoming invoices in one place, whoever sends them.
Documents from any provider in the Peppol network land in your inbox — with a preview, a status and the original available for download.
E-mail on new invoicesYou learn about every incoming invoice immediately.
Notifications go to the addresses you choose; every user manages their own preferences.
Acknowledgement of receiptConfirm collection with a click or an API call.
An acknowledge with a recorded timestamp — useful for internal processes and as proof of when you collected the document.
Automatic response to the senderThe sender gets an acknowledgement without any action from you.
After an incoming document is received and validated, the system sends the MLS response to the sender’s provider — positive, or carrying the error reasons.
Collection into your ERPYour accounting system fetches incoming invoices automatically.
REST API or the standardised SAPI interface for retrieving incoming documents including acknowledgement — no manual forwarding.
API documentation →Invoice and credit noteThe standard Peppol documents per BIS Billing 3.0.
Invoice (code 380) and credit note (381) with a reference to the original document — full support of the EN 16931 European norm.
Self-billingThe buyer issues the invoice on the supplier’s behalf.
Full Peppol Self-Billing 3.0 support — self-billed invoice and credit note with the party roles correctly reversed. Great for logistics, buy-back and commission models.
PDF visualisationEvery document also in a human-readable form.
A clean PDF is generated from the XML automatically — for printing, e-mailing, or colleagues who would rather not read XML.
Original XMLThe legally binding original, always available.
The original UBL document, unaltered — exactly what courts and auditors require as the primary record.
5-level validationEvery document is checked from XML syntax down to the Slovak rules.
XML well-formedness, the UBL 2.1 schema, EN 16931, Peppol BIS rules and the Slovak national rules — an invalid document never leaves us for the network.
Validation reportEvery finding with its rule, severity and exact location in the document.
A per-level summary with error and warning counts, plain-language explanations and fix advice. Export to CSV or print to PDF.
Pre-flight validation APIEXTRATest your documents before you send them for real.
Validation with no invoice created and no credit consumed, on a separate rate limit. The same validation engine as live traffic — ideal for tuning your ERP export.
See the example →Receiver registration checkEXTRAOne call tells you whether a partner is in the Peppol network.
The reachability API returns whether the receiver is registered and which document types they accept — before you even issue the invoice.
See the example →Automatic tax authority reportingThe tax report leaves in parallel with invoice delivery.
The TDD is derived automatically from your invoice and sent to the Financial Administration — data leaves within the statutory deadline with no manual work.
Report status with reasonsSee whether the Financial Administration accepted the report.
The TDD status in the invoice detail and via the API; on rejection, the concrete reason from the FA response.
Archiving for up to 10 yearsOriginals stored safely for the statutory period.
The original XML and the PDF copy with optional archiving for up to 10 years, encrypted at rest with managed retention.
Full-text searchFind a document by anything — including its contents.
Search by number, partner, line contents or a full Peppol ID in the 0245:… form — instant results, archive included.
Filters and CSV exportLists exactly by your criteria, exported in one click.
Filter by status, direction, dates, amounts and partners; download the result as CSV for accounting or reporting.
Delivery evidence trailMaterial for audits and potential disputes.
Receipts, statuses and timestamps for every document; cryptographically signed transport receipts are provided on request.
OpenAPI and documentationA precise machine contract plus guides in English and Slovak.
A public OpenAPI specification (REST and SAPI-SK), a quick start, sample documents and a status reference — your vendor can generate a typed client straight from the spec.
Open the documentation →WebhooksLearn about status changes instantly, no polling.
Push notifications into your system on significant events — delivery, rejection and more — for automated processing.
Documentation →API key and SAPI client managementAccess under control, with expiry and rotation.
Create and revoke keys in the portal; SAPI clients are managed separately. Any credential can be withdrawn at any time.
Users and rolesInvite colleagues or an external accountant, each with their own role.
E-mail invitations, roles with distinct permissions, instant access removal — your accountant works directly, no forwarding.
Two-factor authenticationSign-in protected by a second factor.
Every user enables MFA on their own account — protection even if a password leaks.
Overview dashboardYour account and invoices at a glance.
Daily and monthly counts, pending and rejected documents, a recent-days chart, alerts for low credit or failed deliveries, and quick actions.
Nothing found — try a different term.
How an invoice flows
The user’s view of sending and receiving — from submission through validation and tax reporting to the receipt
Get started in three steps
From choosing a provider to your first invoice
Choose us on the FA portal
On the Financial Administration portal (vpds.financnasprava.sk) select SLOVAKODATA as your certified provider.
Finish onboarding
We receive your verified company data and send an activation invitation. On one page you complete your details, pick a plan and give the consents.
Start invoicing
Once you consent, we register you in the Peppol network. Send and receive invoices in the portal or straight from your ERP via the API.
Test your invoices before go-live
The validation API checks your XML against all five rule levels — the Slovak national rules included — in seconds, without creating an invoice or consuming credit. Ideal for tuning your ERP export while preparing for 2027.
# validate an invoice before submission
POST /api/v1/documents/validate
# response within seconds
{
"valid": true,
"overall_severity": "WARNING",
"validation_levels": {
"L1_xml": "OK", "L2_xsd": "OK",
"L3_en16931": "OK", "L4_peppol": "OK",
"L5_sk": "WARNING"
},
"findings": [{
"rule_id": "SK-W-011",
"severity": "WARNING",
"title": "The seller's legal form and commercial
register entry should be stated",
"location": "/Invoice/cac:AccountingSupplierParty"
}]
}
# is the customer registered in the Peppol network?
GET /api/v1/participants/0245:1234567890/reachability
{ "registered": true, … }Is your customer already on Peppol?
Enter the customer’s Slovak tax ID (DIČ). The answer comes straight from the Peppol network (SML and SMP) — the same check we run before every dispatch.
Plans and pricing
All prices are excluding VAT
Discounted rates with annual billing
Up to 500 invoices a monthExtra invoice €0.15Choose plan
You choose your package in the portal when setting up your account — you start on the free MINI package and can move to a higher one at any time, billed monthly or annually.
Mandatory e-invoicing begins on 1 January 2027.
Frequently asked questions
Is an e-invoice the same as a PDF invoice?
No. A PDF is just a visual document, whereas an e-invoice is a structured XML file built for automated processing — exactly the format ePostman delivers.
Is the application enough without an ERP integration?
Yes — for receiving, previews, status tracking and archiving. Invoices you send are pasted into the portal as ready-made XML documents (UBL) from your accounting system; the portal validates and delivers them. An API integration is an optional next step once your volume grows.
How are credit notes and corrective invoices handled?
A credit note is a standard Peppol document and ePostman supports it, including the reference to the original invoice — self-billing included.
What if I use an external accountant?
You can invite additional users with their own roles — your accountant works with the invoices directly, no e-mail forwarding.
Where is the invoice original stored?
In the service’s secure archive — the original XML and the readable copy, with optional archiving for up to 10 years and a delivery evidence trail for every document.
What do I need on the Financial Administration portal?
A sign-in to the FA portal via Slovensko.sk by a person authorised to act for the company. The link from this page takes you straight to the pre-selected SLOVAKODATA — you only confirm it.
How long does account activation take?
We send the “Activate your account” invitation as soon as the Financial Administration confirms your choice. Activation itself is one page that takes a few minutes; we then start the Peppol network registration automatically.
Can I start after 1 January 2027?
Yes. 1 January 2027 is when the obligation begins, not a deadline for choosing a provider — you can pick us and activate your account at any time. The earlier you start, the more time you have to test your ERP export with pre-flight validation.
Ready for e-invoicing?
Start by choosing your provider on the Financial Administration portal. The rest takes care of itself.