warningPOLKSeF

KSEF-008:GTU code missing

Certain goods/services require GTU (Grupy Towarów i Usług) classification codes. Required for alcohol (GTU_01), fuel (GTU_02), heating oil (GTU_03), tobacco (GTU_04), and other specific categories.

Severity
Warning
Rule set
KSeF
Country
POL
Fix type
INPUT REQUIRED

Engine Classification

Business data required · Explicit input workflow · No assumptions made

Required input: GTU Classification Code

What is KSEF-008?

KSEF-008 is a warning validation rule defined in the KSeF specification (POL national rules). It checks whether gtu code missing.

This is a soft validation failure. The invoice may pass initial transmission, but non-compliant values in this field can cause problems during tax audits, buyer-side processing, or downstream VAT reconciliation.

Why This Error Matters

KSEF-008 is a soft failure. The invoice may pass initial validation, but the non-compliant field can cause issues at the receiving end — tax authorities may flag it during audits, buyer ERP systems may fail to process it, or VAT reconciliation may produce mismatches. Fixing warnings before they accumulate prevents larger compliance gaps.

Validator Behavior

  • ·Generates validation warning
  • ·Error returned: KSEF-008
  • ·Specification: KSeF

How to Fix It

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Technical Reference

SpecKSeF

Code Example

<GTU>GTU_01</GTU>

Common Causes

  • ·GTU requirement overlooked
  • ·New product without GTU assignment
  • ·GTU codes changed by regulation

Seeing this in production? The API handles KSEF-008 automatically. See the fix response →

Frequently Asked Questions

Certain goods/services require GTU (Grupy Towarów i Usług) classification codes. Required for alcohol (GTU_01), fuel (GTU_02), heating oil (GTU_03), tobacco (GTU_04), and other specific categories.

Assign GTU codes to products that require them. You can also use Invoice Navigator's automatic Fixer tool to correct this instantly.

KSEF-008 is a warning that may not always cause rejection, but it indicates a potential compliance issue that should be addressed to ensure full compatibility.

Many instances of KSEF-008 can be automatically corrected using Invoice Navigator's Fixer tool. Upload your invoice and the tool will identify and fix common issues, including gtu code missing.

Last updated: 19 January 2026

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Handle KSEF-008 Automatically in Your Pipeline

The compliance engine auto-remediates this error with controlled safety policies and evidence pack generation.