VAT advisors, accountants, data analysts and IT experts in one team. Simplify your compliance, optimise your tax strategy and stay ahead of every mandate.
Founded in 2017 by a VAT advisor and an IT specialist. Today one team of tax advisors, finance professionals, IT experts and tax technologists, looking at every problem from all sides at once.
Hiccups in internal processes and flaws in data, seen from tax, finance and IT perspectives together.
From tailor-made automated solutions to adopting automated data processes that keep working.
For every question your organisation raises, whether it is VAT, finance or IT related.
Trusted by tax teams at
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Partner From strategic planning to hands-on compliance and tax technology. Scroll through them, or see them side by side.
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Mandate-ready e-invoicing and real-time VAT reporting, integrated into your ERP, tax engine and compliance operations.
Illustrative field-mapping exercise: SAP SD billing fields to connect to their EN 16931 business terms.
02 of 07
Indirect tax for ERP implementations and migrations, using native ERP functionality or a best-in-class tax engine.
Four stacked layers: ERP, tax engine, e-invoicing network and tax authority.
03 of 07
We automate VAT data flows and return preparation: better accuracy, less risk, and time back for your team.
Raw records flow through five gates: extract, validate, map, reconcile and file.
04 of 07
Even the best tax system fails on flawed data. We clean, validate and organise it so compliance holds and reporting improves.
A scanning plane sweeps through messy records; behind it they snap into a clean grid.
05 of 07
Strategic VAT advice, brought to life through digital transformation that scales with the business.
A roadmap drawn across a contour map through four milestones.
06 of 07
Senior VAT specialists who step in from day one, keep filings on time and improve the process while they are there.
A filing calendar of six jurisdictions by twelve months settling, on time.
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Custom software, AI and Avalara e-invoicing middleware, built by engineers who sit next to tax specialists.
A network linking ERP systems through middleware, AI checks and APIs to Avalara and e-invoicing networks.
Working with VATWorkx has been a pleasure these last number of years. Joyce’s knowledge, determination and professionalism is second to none. Super team, super company, highly recommended.
CEOMonitor Excel Mining Solutions 
About Joyce ZijlstraPartner, Indirect Tax The team developed a VAT compliance tool which is also MTD compliant for UK reporting. Extremely professional, and their down to earth personalities forged an excellent working relationship.
VAT ManagerJohn Bean Technologies Product screens use illustrative data.
01 Reconciliation
Reconcile your general ledger against your VAT report and VAT return. Spotting differences and deltas was never this easy.
02 VAT number validation
Validate every customer VAT number against VIES, in bulk, with a confirmation code for your audit file.
03 UK VAT returns
Being compliant in the UK has never been so easy. Multiple ERPs? Not an issue. Create and submit your VAT returns to HMRC in minutes.
Two indirect tax specialists and a software engineer, with more than sixty years of VAT and IT experience between them. Every question gets all three points of view.
Meet the whole team Multidisciplinary answers for every question.
Joyce Zijlstra
20+ years
Consulting on indirect tax
Hermen ter Harmsel
20+ years
In IT security, including identity and access management for public sector and healthcare
Hans Rennings
20+ years
In complex VAT environments
The National e‑Invoice System (KSeF) went live in February 2026, and its mandatory use is being introduced in phases. It reshapes how invoices are issued, received and reported.
Digitization, automated compliance and faceless assessments have transformed how businesses interact with tax authorities. Indirect tax can no longer be handled by a single expert.
Data analytics tools and data visualisation tools serve distinct purposes. Treating them as interchangeable undermines both, and your compliance process with them.
