In short: Accounting in Odoo 20 needs less typing and enforces more control. Vendor bills are filled in for you, you pay bills from Odoo where your bank supports it, and bank entries must now come from bank transactions. The chart of accounts becomes simpler: parent accounts replace account groups and account codes are no longer mandatory. For your accountant and your upgrade, that means a few concrete points of attention.
Every new Odoo version brings something new to accounting, but in Odoo 20 the changes are bigger than usual. They affect the daily work of the bookkeeper, the way the bank is processed and the structure of the chart of accounts. In this article we list the most important changes, based on the official release notes. After that you can read what this means for your accountant and what to watch out for during the upgrade. An overview of all new features in Odoo 20 can be found in Odoo 20: the most important new features for SMEs.
1. Vendor bills: bill line prediction
Entering vendor bills still costs many companies hours every month. Odoo 20 takes over a large part of that work with bill line prediction. Based on previous bills and the description on the line, Odoo suggests which product, which account, which VAT rate and which analytic distribution belong to a bill line.
That saves typing, but the main benefit is consistency. The same kind of cost always ends up on the same account, even when a different colleague does the booking. Do check the suggestions, especially in the first weeks. A prediction is only as good as the history it is based on. If mistakes were made in the past, you don't want them repeated.
The link with purchase orders has also improved. You can unlink a bill from a purchase order again, and you get a summary of the matching. You can also split items on invoices.
2. Paying from Odoo via PISP
Where your bank supports it, in Odoo 20 you pay vendor bills directly from Odoo. This works through a payment initiation connection, also called PISP (Payment Initiation Service Provider). You no longer need to export a payment file and upload it to your banking environment.
Don't simply assume your bank supports this. Check it beforehand, and agree internally who may prepare payments and who may approve them. Paying from your ERP is convenient, but only when the access rights are set up properly.
3. Parent accounts instead of account groups
One of the biggest changes in substance is in the chart of accounts. Account groups disappear and are replaced by parent accounts. In addition, account codes are no longer mandatory.
For new companies this makes setting up a chart of accounts easier. For existing users it is mainly something to check. Many Dutch and Belgian companies work with a fixed numbering scheme their accountant knows, and reports are often built on those numbers. Our advice: keep using account codes, even though they are optional. Your accountant, your integrations and your own reports usually rely on them.
4. Bank: consistency and a reconciliation summary
Odoo 20 enforces bank consistency. Entries on a bank account must come from bank transactions. A manual journal entry that hits the bank account directly no longer fits that model. When closing statements you get clearer warnings.
There is also a new report: the bank reconciliation summary. It shows in one overview where the reconciliation between bank and books stands. That is exactly the overview an accountant asks for at year-end closing.
Do you currently post manual entries on the bank, for example for corrections or opening balances? Then discuss before the upgrade how you will handle that from now on.
5. Matching rules with payment tolerance
Customers don't always pay the exact invoice amount. A few cents difference due to rounding, or a small bank charge, then causes manual work. In Odoo 20, matching rules can have a payment tolerance. Small differences are then still matched automatically.
Set the tolerance deliberately and agree with your accountant on which account the differences are posted. Manual reconciliation has also been extended: it is now possible on any account.
6. Prices including or excluding VAT
On quotations, purchase orders and invoices you can switch between prices including and excluding VAT in Odoo 20. Useful if you sell to both businesses and consumers, or if a supplier quotes prices including VAT. Withholding tax handling has also improved.
7. Duplicate detection and bulk reset
A bill entered twice, or paid twice, is a classic mistake. Odoo 20 recognises duplicates better and uses warning levels, so you can see how likely it is to be a duplicate bill. Need to reset several entries? That can now be done in bulk with "Reset to Draft".
8. Simpler payment reminders
Reminding customers about open invoices has been simplified. That makes it easier to set up a fixed, predictable reminder routine. After the upgrade, do check whether your current texts and terms are still correct.
9. Depreciation models and stock valuation
Asset models have been simplified into depreciation models. The principle stays the same: you define how a type of asset is depreciated, and Odoo creates the entries. The setup has become simpler, though.
Also new: stock valuation is possible without the Inventory app. That is interesting for companies that do want to record stock in the books, but don't need full warehouse management.
10. AI insights into your figures
Odoo 20 can provide financial insights with AI. As with all other AI features in Odoo 20, you need IAP credits for this. See it as help in reading your figures, not as a replacement for the review by your bookkeeper or accountant.
What does this mean for your accountant?
For the accountant, Odoo 20 is more pleasant on a number of points. The bank reconciliation is easier to check thanks to the reconciliation summary, and bank consistency prevents loose corrections on the bank. Bill line prediction leads to more consistent entries. At the same time enough changes to have the conversation beforehand:
- Chart of accounts: agree whether you keep using account codes and how the new parent accounts are structured.
- Bank corrections: agree how corrections and opening balances are processed now that bank entries must come from bank transactions.
- Tolerances: define which deviation may be matched automatically and where the difference is posted.
- Payments: decide who may prepare and approve payments from Odoo.
Your chart of accounts during the upgrade
The change from account groups to parent accounts is the point to watch most closely during the upgrade. So always run the upgrade on a copy of your database first and then check:
- whether your balance sheet and profit and loss give the same result as before the upgrade;
- how your accounts are now arranged under the parent accounts;
- whether your own reports and exports to the accountant still work;
- whether integrations that work with account numbers still find the right accounts.
Do you have integrations through the external API, for example with a bank, webshop or payroll package? Have those checked too. In Odoo 20 the "db" service of the old XML-RPC/JSON-RPC API has been removed. For new integrations the External JSON-2 API is the replacement. Our full step-by-step plan is in Upgrading Odoo to the latest version.
And e-invoicing via Peppol?
Accounting and e-invoicing are increasingly connected. In Belgium, domestic B2B e-invoicing via Peppol has been mandatory since 1 January 2026. In the Netherlands, Peppol is already mandatory towards government, but there is no legal domestic B2B obligation in 2026 and 2027. At EU level, e-invoicing for cross-border B2B becomes mandatory on 1 July 2030. How to set up Peppol in Odoo is explained on Odoo and Peppol and in Peppol in Odoo: sending and receiving electronic invoices.
Frequently asked questions
Are account codes still mandatory in Odoo 20?
No. In Odoo 20 account codes are optional and parent accounts replace account groups. For Dutch and Belgian companies we recommend continuing to use account codes, because accountants, reports and integrations usually rely on them.
Can I pay vendor bills from Odoo in Odoo 20?
Yes, where your bank supports it. Odoo 20 pays vendor bills through a payment initiation connection (PISP). Check beforehand whether your bank supports this.
What is bill line prediction in Odoo 20?
On vendor bills, Odoo itself suggests the product, the account, the VAT rate and the analytic distribution, based on previous bills and the description on the line.
What should I watch out for when upgrading my accounting to Odoo 20?
Test the upgrade on a copy first. Check whether your balance sheet and result stay the same, how your accounts fall under the new parent accounts, how you will process manual bank entries from now on and whether your integrations still work.
In conclusion
Odoo 20 makes accounting faster and easier to verify, but only if the setup is right. Want to know what the upgrade means for your administration, or have your accounting set up in Odoo? At DAADit, AI builds and a consultant checks, at a fixed price of €1,000 per app. See our prices, contact DAADit Group or take the free Business Scan.