What is invoice decreeing and when is it necessary?

Invoice assignment is a mandatory activity for all entrepreneurs. It results from the provisions of the Accounting Act. We explain what it is and how the issue of assigning invoices will change when the obligation to use the National e-Invoice System comes into force.
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What is the posting of accounting documents?


Invoice declaring is another way of saying that the evidence of transactions carried out is checked and classified in the books of account. Among other things, every company must check all cost invoices and bills it pays regularly in this way.

What should I pay attention to when verifying invoices?

  • On whether the document is complete – contains all the necessary data, amounts, filled fields, signatures, stamps, etc.
  • On whether the document is reliable – consistent with the real state of affairs, confirming a real transaction.
  • On whether the document is error-free – filled out with the correct data, annotated with the correct amounts and annotations, and free of mistakes that prevent further processing of the invoice.

Types of accounting evidence


Although it is customary to talk about invoice decertification, the process involves not only invoices, but all accounting evidence. The collection includes:

  • textures,
  • RR VAT invoices,
  • customs documents,
  • Documents specifying a reduction in deductible expenses or an increase in revenue,
  • accounting notes,
  • daily statements of evidence,
  • evidence of transfers,
  • proofs of postage and bank charges,
  • other evidence of fees.

What must the accounting evidence contain?


  • Specifying the type of proof and its identification number,
  • identification of the parties carrying out the business operation – including contact information and names of the entities, participating in it,
  • A description of the operation and its value,
  • date of operation,
  • The date of the proof (if different from the date of the operation),
  • signature of the issuer of the evidence and the person to whom the assets were issued or from whom they were accepted,
  • a statement confirming the verification and qualification of the document for inclusion in the books of account, including an indication of the month and the method of inclusion of the evidence in the books of account – this is the point we call decertification,
  • Signature of the person responsible for these indications.

Storage of accounting documents – electronic or traditional


Invoices and other accounting evidence must be stored and archived in a strictly defined manner, as stated in Art. 112a of the VAT Law. According to the regulations, taxpayers are required to keep the invoices that they themselves have issued and received. These documents should be divided into accounting periods – so that they can be easily found, and the authenticity of their origin, integrity of content and legibility can be confirmed until the expiration of the statute of limitations on tax liability.

If an entrepreneur collects accounting documents in paper form, he should keep them in the country – as long as he has a place of business in the country. This provision does not apply if the taxpayer stores invoices in an electronic form that allows granting access to these documents to the head of the tax office, the head of the National Tax Administration or the director of the Tax Administration Chamber.

It is the taxpayer’s responsibility to provide immediate access to stored invoices to the relevant authorities:

  • To the head of the tax office,
  • To the head of the customs and tax authority,
  • To the director of the Tax Administration Chamber,
  • To the head of the National Tax Administration.

In addition to access, the taxpayer must also provide the above. institutions the ability to download and process electronically stored documents.

How is invoice decreeing done?


The invoice decreeing process can be done manually or electronically. The traditional way is usually supported by the use of ready-made stamps – then it is enough to fill in the missing information. The electronic way is used by companies that keep their accounts using specialized software.

Regardless of whether the taxpayer decrements manually or with the use of software, it must verify that the data on the invoices (in particular, the parameters of the transactions entered into) are consistent with the facts.

Searching for information on invoice decreeing, you may come across a description of four types of decreeing:

  • Omnibus decreeing involves making a combined entry of all source evidence listed individually in the omnibus evidence.
  • Corrective decreeing involves making corrections to previous accounting evidence.
  • A substitute decree is issued if the taxpayer does not have external, third-party source evidence.
  • The billing decree applies to previously made entries, but takes into account the new criteria – if any.

How will the National e-Invoicing System affect the obligation to decree invoices?


Verification of attachments in invoices

There is, however, a spoonful of tar in this barrel of honey. The standardization of the invoice format has forced changes in the number of fields, or more precisely: its limitation. Within the National e-Invoice System, it will not be possible to add an attachment or note to a structured invoice, but only to add an annotation or link to the attachment in fields such as AdditionalDescription and AdditionalInfo. In this situation, it is expected that some taxpayers will use the option of sending an invoice attachment outside the System – for example, via email.

This could potentially generate a problem just during the invoice decreeing process – some companies will add a link to the attachment on the invoice, in the AdditionalDescription field, other taxpayers will use the AdditionalInfo field, and still others will send the attachment by email. From the perspective of the person doing the decrementing, this can prove to be quite a handicap – especially if he or she has to handle dozens or even hundreds of invoices in a given accounting period in this way.

Errors found on online invoices

If the decreeing person encounters an error on an invoice, it will be necessary to contact the purchaser of the invoice and communicate this information to him. This one, in turn, will have to contact the invoice issuer and ask not for a correction note, but for a correction invoice. This is another of the changes that the introduction of the National e-Invoicing System will trigger. Correction notes will not be allowed – correcting invoices are required instead. For obvious reasons, it will take a little longer.

A correction invoice must contain a number of information in order to be recognized by the National e-Invoice System:

  • The identification number of the original invoice issued in KSeF,
  • own identification number,
  • date of issue.

What if the TIN turns out to be wrong on the invoice?

It may happen that a taxpayer receives an invoice for a transaction that he does not recognize. An invoice entered into KSeF with an incorrect TIN will go to a taxpayer who has nothing to do with the transaction in question.

When the parties to the transaction notice the mistake, the invoice issuer must zero it out and then issue an adjustment invoice, reducing the value of the tax base to zero. Only then can the issuer of an invoice with an incorrect TIN number issue another invoice, this time taking care to enter the correct TIN number.

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