Chart of accounts, dimensions, account structures and the death of the Dimension Set ID
How Business Central's per-company G/L Account table and reusable Dimension Set ID model translate into D365's shared chart of accounts, financial dimensions, account structures and advanced rules — and why the surrogate key must never travel.
What you will be able to do
Map every Business Central G/L Account type to the correct D365 main account type and category
Decompose Dimension Set IDs into business values and validate them against target account structures
Design account structures and advanced rules that reproduce Business Central's dimension combination constraints
Explain why the Dimension Set ID is a source surrogate key that must never become a target business key
Plan the Wave 1 chart-of-accounts migration sequence
Introduction
Business Central's finance model is shaped by a per-company chart of accounts and a dimension system that stores recurring dimension combinations behind a numeric Dimension Set ID.
The Business Central chart of accounts
Each Business Central company owns a distinct G/L Account table. Accounts have a type that governs their posting and presentation role:
Normalising the chart across companies
When multiple BC companies migrate into legal entities that share a single D365 chart, conflicts arise. Two companies may use account 4100 — one for domestic revenue, the other for intercompany revenue. The resolution options are:
Business Central dimensions — architecture and limits
Regardless of exposure level, all dimensions ultimately resolve to Dimension Set Entries on posted transactions. The Dimension Set ID on a G/L Entry, Customer Ledger Entry, Item Ledger Entry or any other posted record is a foreign key to the Dimension Set Entry table, which holds the individual dimension/value pairs.
D365 financial dimensions and account structures
D365 financial dimensions serve the same analytical-tagging role as BC dimensions but under a structural governance layer:
Building account structures from combination rules
Extract all active Dimension Combinations and Dimension Value Combinations from BC. Group dimensions by co-occurrence on actual posted transactions (not only configuration). Identify the primary structure — the most common combination of dimensions across all posting accounts.
The migration algorithm: from Dimension Set ID to valid ledger dimensions
The playbook prescribes a nine-step algorithm for dimension migration. In summary:
Wave 1 sequencing for chart and dimensions
The chart-of-accounts and dimension configuration belongs to Wave 1 — Master configuration, chart of accounts and financial dimensions. The internal dependency order is:
Knowledge check
Summary
Business Central's finance model is compact — a per-company chart and a dimension system optimised for reuse through surrogate set IDs. D365's model is governed — a shared chart constrained by account structures that enforce valid combinations at the segment level.