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Master data and TRNs: the work to do first

Structured invoicing fails on data quality, not on software. Validate customer and supplier TRNs, deduplicate records, standardise tax codes and fix legal names and addresses before you connect to a provider — this takes months, not a weekend.

Last reviewed 2026-09-10

Why this is the real project

When a business connects to a service provider and half its invoices bounce, the cause is almost never the connection. It is a customer record with no TRN, three versions of the same supplier, an item with no tax code, or a legal name that does not match the trade licence. Under PDF invoicing these were cosmetic; under structured invoicing they are hard failures.

What to check

DataWhat good looks like
Customer TRNPresent, correctly formatted, verified against the customer's own records
Supplier TRNPresent for every supplier you claim input VAT from
Legal entity name and addressMatches the trade licence, not the trading name staff use
Tax codesOne standard set, mapped to every item and service
Item catalogueNo free-text-only lines on B2B invoices
Currency and roundingConsistent rules applied by the system, not by the person invoicing

A workable sequence

  • ·Export your customer and supplier lists and sort by missing TRN — that list is your first project.
  • ·Merge duplicates before you enrich them, or you will enrich the same company twice.
  • ·Fix the top 20% of customers by invoice count first; they cause most of the volume.
  • ·Put a validation rule in front of new record creation so the problem stops growing.
  • ·Re-run the missing-TRN report monthly until it is empty, then keep running it.

Groups and firms

Multi-entity groups and accounting firms have the same problem multiplied by the number of ledgers. What helps is a single exception list across all of them, ranked by how many invoices each bad record will block, rather than a clean-up project per entity run at a different pace.

Official sources

General information, not tax or legal advice. Confirm your own position with the Federal Tax Authority or your tax adviser.

See how this looks on a dashboard

TaxFlow Cockpit shows transmission, acknowledgement and rejection across your entities and accounting platforms in one view.

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