Poland Einvoice

Poland E-Invoicing -- KSeF (Krajowy System e-Faktur) Skill v1.0

General reference only. This skill is general tax/accounting reference material for AI-assisted workflows. It has not been reviewed for any specific person's facts, documents, elections, deadlines, residency, filing status, or local procedures. Do not rely on it to file, pay, amend, or take a tax position without review by a qualified professional in the relevant jurisdiction.

Section 1 -- Quick Reference

Section 2 -- Mandate Scope

Who Must Comply

Exemptions

• Invoices issued by taxpayers not registered for Polish VAT
• Tickets and simplified invoices for amounts up to PLN 450 (EUR ~100) -- exempt from KSeF but subject to Veri*factu-like fiscal printer rules
• Invoices from the agricultural flat-rate scheme (rolnik ryczałtowy) issued by the buyer (RR invoices use a separate FA_RR(1) schema)

Timeline Summary

Section 3 -- Technical Format

FA(3) Schema

FA(3) Root Structure

Key Differences from EN 16931

Section 4 -- Mandatory Fields

Naglowek (Header)

Podmiot1 (Seller)

Podmiot2 (Buyer)

Fa (Invoice Body)

Adnotacje (Annotations -- Mandatory Booleans)

GTU Codes (Goods/Services Classification)

Section 5 -- Transmission Method

KSeF API 2.0

Submission Flow

1. Authenticate -- open a KSeF session using certificate, trusted profile, or token
2. Submit -- send FA(3) XML file via API endpoint
3. Validate -- KSeF performs XSD and semantic validation
4. Accept or Reject -- if valid, KSeF assigns a unique KSeF number and timestamp; if invalid, returns error
5. UPO -- download Urzędowe Poświadczenie Odbioru (official receipt of acceptance) as proof of issuance
6. Buyer access -- buyer retrieves invoice from KSeF using their NIP credentials

Alternative Submission Methods

Offline Mode

If KSeF is unavailable (system downtime declared by MF), businesses may:

1. Issue invoices outside KSeF with offline numbering
2. Submit to KSeF within 7 days of system restoration
3. The date of issue (P_1) remains the original date; the KSeF date is the submission date
4. Offline invoices require specific handling and must reference the offline period

KSeF Number Format

Format: {NIP}-{YYYYMMDD}-{sequential number} -- assigned by KSeF upon acceptance. This number becomes the primary legal identifier of the invoice.

Section 6 -- Validation Rules

XSD Validation (First Layer)

KSeF validates every submitted XML against the FA(3) XSD. Approximately 70% of rejections are XSD validation errors.

Semantic Validation (Second Layer)

Common Rejection Scenarios

Section 7 -- Tax Computation Rules

VAT Rates (2025/2026)

Rounding

• Line net amount (P_11): 2 decimal places
• Unit price (P_10): up to 8 decimal places
• Quantity (P_9A/P_9B): up to 6 decimal places
• VAT amount per line (P_11A): 2 decimal places
• Gross total (P_15): 2 decimal places
• Use banker's rounding (round half to even) for consistency with KSeF validation
• Sum of line amounts must exactly equal the corresponding summary field -- no tolerance

Multi-Rate Invoice Handling

• Each applicable VAT rate has dedicated summary fields (P_13_1/P_14_1 for 23%, P_13_2/P_14_2 for 8%, etc.)
• Line items reference the rate via P_12
• If a single invoice has lines at 23%, 8%, and exempt, all three summary pairs must be populated
• P_15 (gross total) = sum of all P_13_x + sum of all P_14_x

Split Payment (Mechanizm Podzielonej Płatności -- MPP)

• Mandatory for transactions > PLN 15,000 gross involving goods/services listed in Annex 15 to the VAT Act
• Set annotation P_18A = 1 when MPP applies
• Invoice must include the phrase "mechanizm podzielonej płatności"
• Payment is split: net amount to seller's account, VAT amount to seller's VAT account

Corrective Invoices (Faktury Korygujące)

• Must reference the original KSeF number of the corrected invoice
• Show both "before" and "after" values, or the difference
• Use same FA(3) schema with corrective-specific fields populated
• KSeF validates that the referenced original invoice exists and belongs to the same seller NIP

Section 8 -- Archiving Requirements

Section 9 -- Penalties for Non-Compliance

Financial penalties take effect from 1 January 2027. During 2026, the practical consequences of non-compliance are primarily operational (invoices not legally valid for VAT deduction).

Practical Risks During 2026 (Before Penalty Enforcement)

• Invoices not submitted through KSeF are not legally valid for VAT deduction purposes
• Trading partners may refuse non-KSeF invoices
• Audit exposure increases as KAS cross-references KSeF data

Section 10 -- Interaction with Tax Skills

VAT Return Integration

• KSeF data directly feeds into JPK_VAT (Jednolity Plik Kontrolny) -- the standard audit file for VAT
• JPK_V7M (monthly) and JPK_V7K (quarterly) declarations must reconcile with invoices in KSeF
• KSeF invoice numbers are used as references in JPK records
• GTU codes from KSeF invoices must match GTU markings in JPK_VAT
• Split payment (MPP) markers from KSeF feed into JPK_VAT classification
• Tax authorities can automatically cross-check KSeF invoices against JPK declarations in real-time

e-Urząd Skarbowy Integration

• The e-mikrofirma module in e-Urząd Skarbowy connects directly to KSeF
• Taxpayers can issue invoices in KSeF and transfer data directly to VAT records without manual re-entry
• Pre-filled VAT returns based on KSeF data are progressively being developed

Income Tax Integration

• For sole proprietors (JDG -- jednoosobowa działalność gospodarcza), KSeF invoice data feeds into the annual PIT-36/PIT-36L return
• Revenue and cost figures must reconcile with KSeF records
• KSeF provides an authoritative source for income verification during audits

Cross-Border Considerations

• All invoices issued by Polish VAT payers, including intra-EU and export invoices, must be reported through KSeF
• Intra-EU supplies must be reported in both KSeF and the EU VAT Information Exchange System (VIES) via VAT-UE declaration
• Import VAT (from customs declarations) is handled separately but must reconcile with purchase invoices in KSeF

PEF (Platforma Elektronicznego Fakturowania) Integration

• B2G invoices previously submitted through PEF are being migrated to KSeF
• From 1 February 2026, PEF forwards invoices to KSeF production environment
• Public entities receive invoices through KSeF with PEF acting as an intermediary during transition

Disclaimer

This skill and its outputs are provided for informational and computational purposes only and do not constitute tax, legal, or financial advice. Open Accountants and its contributors accept no liability for any errors, omissions, or outcomes arising from the use of this skill. All outputs must be reviewed and signed off by a qualified professional (such as a doradca podatkowy, biegły rewident, or equivalent licensed practitioner in your jurisdiction) before filing or acting upon.

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Source: OpenAccountants — open tax Guides for AI, reviewed by named CPAs/CAs/EAs. Quality: source-cited draft. For always-current figures and named-accountant backing, connect the OpenAccountants MCP server (openaccountants-mcp).