Turn the Accounting Flexfield, its value sets and its cross-validation rules into a main account, a governed financial dimension set and account structures — and re-qualify secondary ledgers, reporting currencies and encumbrance before anyone assumes they carry across.
The Accounting Flexfield is the most recognisable thing about an EBS estate, and it is the construct that survives least intact.
Every segment in every flexfield structure gets exactly one of three classifications.
A D365 account structure permits one main account plus up to ten financial dimensions — eleven segments in total. That is a hard design constraint and it is easy to exhaust, because the target usually needs dimensions the source did not have as segments.
Cross-validation rules in EBS restrict which segment combinations may be used. They read like data, which is why teams try to convert them row by row. That approach fails, because D365 expresses the same policy structurally.
A D365 ledger carries exactly two configurable currencies: the accounting currency and the reporting currency. That is generous for most estates and constraining for a few, and the constraint has to be discovered early because it interacts with the legal-entity design.
The gap register lists encumbrance and public-sector variants as high business impact with a pointed qualifier: only applicable where used, but high-risk when present.
Period mechanics translate more comfortably than most of this module. EBS opens and closes GL periods per ledger, with subledger periods closing ahead of the general ledger. D365 controls period status on the ledger calendar per legal entity, with module-level close activity feeding it.
Chart and dimension design sits in the first wave of the migration plan, before master data and before anything transactional. That ordering reflects a dependency rather than a preference: nothing else can load until main accounts, financial dimensions and account structures exist and are frozen.
The Accounting Flexfield does not migrate; it decomposes. The natural-account segment becomes the main account, approved non-account segments become financial dimensions, value sets supply the permitted values, and cross-validation rules become account structures and advanced rules that express the same policy structurally.