Poland KSeF E-Invoicing

The problem

Polish businesses are required to issue invoices through KSeF (Krajowy System e-Faktur) in the mandated national XML structure. SAP Business One posts a perfectly good A/R Invoice, prints a perfectly good Crystal Report, and then stops. There is no native export in the required schema, no session handling against the national platform, no place to store the KSeF reference number that becomes the legal identifier of the invoice, and no way for an accountant to see at a glance which of yesterday's 140 documents were accepted and which were rejected for a missing NIP or a malformed line-level tax code.

The workaround most sites fall into is a spreadsheet: export invoices, hand them to a bookkeeper, upload them somewhere else, then type reference numbers back into a UDF one at a time. That is fine for five invoices a day. It is a liability at fifty, and it collapses entirely when a correction invoice has to reference the KSeF number of the original.

This is a fixed-deadline problem with no partial credit. Either the document reached KSeF and you hold the reference, or you have not legally issued it.

What ECOSIRE builds

We build a per-tenant SAP Business One add-on that closes the loop between your marketing documents and KSeF, using SAP's supported extensibility surfaces only — no direct writes to base tables, no unsupported schema changes.

Document capture and mapping

The add-on reads A/R Invoices, A/R Credit Memos and A/R Correction Invoices through the Service Layer (Invoices, CreditNotes, CorrectionInvoice) and maps them into the KSeF structured XML. Mapping is explicit and reviewable: Business Partner master data (NIP, address, GLN where used), document header fields, line-level item codes, quantities, unit prices, discount handling, and the VAT breakdown assembled from the document's tax codes. Where a required field has no natural home in standard SAP B1, we create a UDF on the correct object (OINV, OCRD, ODLN as relevant) and drive it from a validated dropdown or a formatted search rather than free text.

Submission and session handling

A dedicated UDO holds the submission record: one row per attempt, carrying the source document key, the generated XML payload, the timestamp, the session identifier, the response body and the resulting status. Authentication and session lifecycle against the national platform are handled inside the add-on service, with credentials held outside the company database. Retries are idempotent — a document that already carries a confirmed KSeF number cannot be resubmitted by accident.

Status tracking and the reference number

On acceptance, the KSeF reference number and issue timestamp are written back to UDFs on the source document and locked against manual edit. On rejection, the platform's error payload is parsed into a readable reason and surfaced on the submission record, so the person fixing it sees "buyer NIP missing on BP C10023" rather than a raw fault code. A Crystal Report layout is delivered showing submitted, accepted, rejected and pending documents for any date range, with drill-through to the offending document.

Corrections and the reference chain

Correction invoices must point at the KSeF identifier of the document they correct. The add-on resolves that chain automatically from the SAP B1 base-document link, so a user issuing a correction from the original invoice does not have to know or type the reference.

Controls before the document leaves

Pre-submission validation runs against the same rules as the schema: mandatory Business Partner tax identifiers, tax code completeness on every line, currency and rounding consistency, and document numbering series integrity. Failures are shown before submission, not after rejection. Where you want a human gate, the add-on hooks into standard approval procedures so that an invoice above a threshold requires sign-off before it is transmitted.

Logging and audit

Every request and response is retained on the UDO with its payload, so an auditor asking "prove this invoice was issued and when" gets an answer from inside SAP B1 rather than from a mailbox.

Who this is for

Companies running SAP Business One with a Polish legal entity that issue A/R Invoices in Poland — manufacturers, distributors, wholesalers and services businesses. It is equally relevant to multi-country groups where the Polish subsidiary is one company database among several and the group wants Poland handled without a separate finance system running beside SAP B1.

It is not for you if your invoice volume is a handful per month and you are content to key them into the government portal by hand. The value of this add-on is in removing repeated manual handling and in making the reference number a first-class field on the document.

Technical framing

Built as a SAP Business One add-on and integration layer using the Service Layer (REST) for document read and UDF write-back, the DI API where a transaction requires it, and UDO/UDF/UDT for the submission ledger and configuration. Compatible with SAP Business One 10.0 on Microsoft SQL Server and on SAP HANA, on-premise or cloud-hosted. Configuration — endpoints, credentials reference, numbering series in scope, threshold rules — lives in a setup UDT rather than in code, so a change of environment does not need a new build.

How delivery works

Nothing here is pre-built and there is no instant download. Every deployment is built for your company database and your document flow.

1. Scoping call. We walk your actual invoice types, numbering series, tax codes, Business Partner master data quality and correction process. We identify what is missing for the schema before anything is quoted. 2. Fixed quote. You receive a written scope and a fixed price. No hourly drift. 3. Build. Typical lead time is 2 to 4 weeks from signed scope, depending on how many document types and how much master-data remediation is in scope. 4. Install into your test company. We install into your test database first and run your own real documents through it end to end, including a rejection and a correction, so you see the failure path as well as the happy path. 5. Install into production. Once you sign off on test, we install into the production company database and run a supervised first submission window. 6. Support. A support window follows go-live for defect fixes and for adjustments arising from real use.

You own the deployment. Source is delivered with it, documented, and installable by your own team or your SAP B1 partner.