When a company that operates under its own regulatory framework decides to move its accounting to Odoo, the temptation is to open the system and start loading balances. After several migrations, my advice as an accountant is the opposite: the decisions that matter are made before a single journal entry is recorded.
The chart of accounts is not copied, it is redesigned
Copying the chart of accounts from the old system drags along years of accounts nobody uses and sub-accounts that exist out of habit rather than need. In a regulated business, some reports also require specific groupings. First, define the reports the company has to deliver, and build the structure from there, not the other way around.
Analytics from day one
Analytic accounting is the part that gets postponed the most and costs the most to add later. If the business needs to see results by product line, by project or by cost center, those dimensions must exist before the opening balances are loaded. Adding them after months of transactions means reclassifying entries one by one.
Lock periods, even if it feels like red tape
Odoo lets you set a lock date so nobody can change periods that are already closed. In a migration, it is your best protection: once a month's load is reconciled, it gets locked, and the figures stop moving unless someone consciously decides to change them.
Bulk import of journal entries, with a dry run
Loading history in bulk saves weeks, but only if you rehearse it. Test with one month, compare it against the trial balance from the old system, and fix the template before repeating the process with the rest. A difference of a few cents in the dry run is almost always a rounding or currency issue, and it is worth understanding before you multiply it by twelve months.
Checklist before go-live
Required reports defined, along with their account structure.
Analytic dimensions agreed with the decision makers.
Lock date set for the loaded periods.
Import dry run with one month and a balanced trial balance.
A person responsible for validating each close before it is locked.
A well-organized migration goes unnoticed: the first close in Odoo matches the last one from the old system. If you are about to start one, let's talk about the structure before the data load.