How does RGS (referentiegrootboekschema) work?
The link is a translation, not a replacement. You keep your own account numbers and your own descriptions; you only attach a code that has meaning outside your bookkeeping.
The benefit only becomes visible at handover. As long as you do everything in one package, you notice nothing. As soon as you export to an adviser, switch to another system or have to deliver a report, an empty code field is the difference between reading in and retyping.
In an auditfile the codes hang on the general ledger account in optional fields. Optional here means the file is valid without them, not that it is just as usable without them.
Where is RGS (referentiegrootboekschema) in the law?
For this term there is no statutory basis to refer to, and that is not an omission but the state of affairs. It is a term from bookkeeping practice, not a legal obligation with its own article.
What does apply sits one level higher: under Article 52 of the Dutch General State Taxes Act (Algemene wet inzake rijksbelastingen, AWR), your bookkeeping must be verifiable within a reasonable time. How you set that up is not prescribed by law.
What does basestep do with RGS (referentiegrootboekschema)?
Linking the chart of accounts to RGS codes belongs with the auditfile export and is planned together with it. The basestep chart is small and fixed, which makes the linking simpler than with a chart every user sets up themselves.
All calculations, explanations and signals in basestep are calculation support and instruction, not tax or legal advice. Amounts are estimates based on your own input; the Dutch tax authority (Belastingdienst) sets the assessment.
Where does it go wrong with RGS (referentiegrootboekschema)?
The two mistakes you run into most often in practice with this term, and what they cost you.
Ignoring empty codes until the switch
By the time you switch, it is too late to link calmly. An empty code field then costs the recipient manual work.
Guessing codes
A code that roughly fits gives a translation that is roughly right. In a report to a bank, that is a problem.
Further reading
Three places this term is tied to, inside this glossary and beyond.