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PN Scripts

Business apps

Zaverka

by PN Scripts

A Windows app that checks EU VAT numbers in VIES, one at a time or a whole list from a CSV file, with the name, the address and a consultation number you can keep as proof, after catching typing mistakes offline.

  • .NET 10
  • C#
  • Windows Forms
  • VIES REST API
  • Coming soon

Coming soon

Not published on its store yet, so there is no buy or download link. PN Scripts does not take payment for it here.

Business apps
The Zaverka window with a German VAT number marked valid, the demo company name and address and a consultation number

What it solves

The gap

Checking client VAT numbers one by one on the VIES website is slow, keeps no record and lets typing mistakes through, while a missed invalid number can cost the VAT exemption on an intra-EU invoice.

What it is

Zaverka checks single numbers or whole lists in VIES from a small Windows app, keeps the consultation number and a history of every answer, and catches impossible numbers offline first.

How you use it

Every client VAT number checked, explained and on record, without the VIES website.

A careful, private VIES checker for accountants and businesses that invoice other EU companies.

Who it is for

Use it when

  • An accountant who checks the VAT numbers of all clients before the monthly VIES declaration
  • An online shop that verifies a business customer's VAT number before invoicing without VAT
  • An office that keeps the consultation number of every check for a tax audit

Built for

  • Accountants and bookkeeping offices in the EU, especially in Bulgaria
  • Small businesses and online shops that invoice companies in other EU countries

What is inside

Asked straight from VIES

Zaverka uses the European Commission's VIES REST service. A valid number shows the name and address the member state shares; with your own VAT number entered, VIES also returns a consultation number, shown and saved with the time of the check.

Typos caught first

Formats for the 27 member states and Northern Ireland and check digits for 25 of them are checked before any request. Wrong digits, unknown country codes and missing codes are explained in words and never sent.

Lists from Excel

Open or drop a CSV, or paste a column. Separators, UTF-8 and Windows-1251 are recognised, and so are column names such as VAT number or ИН по ДДС. Results are saved as CSV that Excel opens with Cyrillic intact, with formulas in outside data neutralised.

A record of every check

Every VIES answer is appended to history.csv in your profile and shown in the History tab. Busy or offline member states are marked try later and can be retried with one click.

Specs

Availability
Coming soon
Vendor
PN Scripts
Type
Software
Pricing
One-time purchase Price to be announced.
License
Commercial license
Deployment
Download (zip with a self-contained Zaverka.exe, and the source code)
Maturity
v1.0.0

Compatibility

Platform or runtime Supported versions Tested up to
Windows 10 (64-bit) or newer Wine 11 (Windows 10 mode)
.NET 10.0 (included) or newer 10.0.12

Stack

  • .NET 10
  • C#
  • Windows Forms
  • VIES REST API

Zaverka is coming soon

It is finished and tested. It is not on sale yet; this page will say where to get it when it is.

Coming soon

Not published on its store yet, so there is no buy or download link. PN Scripts does not take payment for it here.

Questions

A Windows desktop app that checks EU VAT numbers in VIES, one at a time or a list from a CSV file, with a history of every answer and a command line for scripts. It comes as a zip with a self-contained Zaverka.exe, a README in English and Bulgarian, a sample CSV and the source code.

Windows 10 or 11, 64-bit, and an internet connection to ec.europa.eu. The .NET 10 runtime is inside the program, so nothing else is installed. Installing for the current user is optional and needs no administrator rights.

It does not file VIES declarations, check numbers outside the EU and Northern Ireland, or say anything about a trader beyond what VIES returns. It was tested under Wine on Linux, not yet on a real Windows 10 or 11 computer, and the live VIES service was not part of the automated tests; the Commission's test service was.

Made by PN Scripts, a Sofia studio that builds games and tools, in C# with .NET 10 and Windows Forms. Created with AI assistance; PN Scripts checked it with 81 xUnit tests, including 7,600 check-digit cases compared with an independent library, and an automated check of the release zip on a fresh Wine prefix: install, command line, the VIES test service and the window in English and Bulgarian.

It is not on sale yet. When it is, this page will link to the store; PN Scripts does not take payment on this site.