An honest account from our own practice - not about which alternative to pick, but about how the move itself plays out.
We help SMB and mid-market companies move off SAP. The question I want to answer here is not “which system is better” - we have set that out honestly elsewhere - but the question that comes next: what does the switch actually look like? What comes across, what does not, how long does it take, and what does it cost compared to staying?
If you first want to know which alternative fits you, or how Odoo stacks up against SAP head to head, start with our overview of the best SAP alternatives or the full Odoo vs SAP comparison. This article is about the migration itself.
Why companies come to us
Most conversations share the same trigger. SAP is winding down mainstream support for ECC and pushing customers toward S/4HANA via RISE with SAP. That is not an update but a re-implementation: new data models, reconfigure, retrain, pay again. At that point a sensible owner asks: if I have to re-implement anyway, do I want another heavy SAP - or a platform that fits my scale?
The second trigger is wear. The system works, but every change costs a consultant, every report costs a day, and the package was built for multinationals with hundreds of users while you have fifty. The forced migration is the nudge, not the cause.
What the move is and is not
The most important thing I set straight up front: a SAP-to-Odoo migration is not a lift-and-shift. You do not copy SAP configuration into Odoo. You redesign your processes in a lighter system and deliberately leave behind the complexity that crept into SAP over the years.
That feels like more work, but it is the relief. Most SAP frustration we encounter is not about what SAP can do, but about what it costs to make it do anything. By choosing what you actually need during the switch, the system - and running it - gets lighter immediately.
The phases of a migration
Not a generic demo, but a fixed route. Here is how we approach it:
- Process analysis and fit-gap - we walk your process from lead to invoice and decide what fits standard Odoo, what needs configuration, and what genuinely needs customisation or an integration. This is where most risks surface.
- Data migration plan - which master data, open items and live orders come across, and which history you archive. Here it becomes clear early how clean your SAP data really is.
- Configuration - we build the core processes in Odoo: sales, purchasing, stock, production, projects and finance on one platform.
- Parallel running and testing - on real scenarios: quote, order, purchasing, production order, delivery, invoice, post-calculation. Not on paper, but with your own data.
- Go-live, phased - core first, then the rest. We would rather not do a big bang when phasing is safer.
- Optimisation - after the switch, sharpening up on what turns out to chafe in practice.
Realistic hours, cost and lead time per phase are in our implementation benchmark.
What migrates, what does not
A common misconception is that everything has to move. It does not, and usually it should not.
- Across: customers, suppliers, items, bills of materials, open receivables and payables, live sales and purchase orders, current stock levels.
- Not, or only as an archive: years of transaction history, closed financial years, dead items and customers. You keep those in a read-only export or archive. You lose nothing, but you also do not drag pollution into your new system.
The switch is an ideal moment to clean up your data. Almost every SAP export we open contains duplicate customers, dead items and fields nobody uses anymore.
The sum: staying versus switching
The honest question is not only “what does switching cost”, but “what does switching cost compared to the S/4HANA migration that is otherwise coming for you anyway”. Below we put both side by side, as an indication, for an SMB or mid-market company of roughly 30 to 50 users, over five years.
| Cost item (5 years, indicative) | S/4HANA via RISE | Odoo switch |
|---|---|---|
| Licences / subscription | high | low to medium |
| Implementation / reconfiguration | very high | medium |
| Hosting & infrastructure | included, but pricey | low |
| Maintenance, changes & customisation | high (consultant per change) | low to medium |
| Training & adoption | high | medium |
| Total TCO over 5 years | reference (100%) | roughly 30 to 50% |
In our practice the total five-year cost of an Odoo switch for an SMB comes out far lower than an S/4HANA project - often by a factor of 2 to 3. The biggest saving is not in the licence, but in implementation and in the fact that you can make changes yourself instead of hiring a consultant for every adjustment.
Note: these are ranges, not a quote. Actual cost depends on scope, modules, customisation, integrations and how clean your data is. For your situation we make a focused estimate rather than a table.
What goes wrong - and how we prevent it
After dozens of projects you see the patterns. Three things go wrong most often:
- Cleaning data too late. Discover the data quality only during the migration and you lose time. We deliberately start early.
- No internal process owner. An ERP switch is not an IT project you outsource entirely. Without someone internal to make calls, every project stalls.
- A big bang where phasing was possible. Converting everything in one weekend feels decisive, but it stacks risk. Going live in phases is almost always safer.
None of these three is a surprise once you have done it often. So most of our work sits before go-live, not after.
When you are better off staying on SAP
We sell Odoo, but we are honest about the line. If you are genuinely enterprise - dozens of legal entities, multinational consolidation, heavy industry and compliance requirements, with the budget and team to run SAP well - then S/4HANA offers depth a lighter platform does not have out of the box. Then switching is not relief but risk. We say so plainly.
For most of the SMB and mid-market companies we speak to, that is not the situation. There, the forced S/4HANA migration is exactly the moment to choose deliberately rather than be carried along.
Frequently asked questions
How long does a migration from SAP to Odoo take?
In our experience an SMB or mid-market switch runs from a few months to about a year, depending on scope, data quality and how much customisation you actually need. That is far shorter than a typical S/4HANA re-implementation, mainly because you go live in phases instead of one big bang.
What migrates from SAP to Odoo, and what does not?
Master data, open items and live orders come across. Deep transaction history we usually keep in an archive or read-only export instead of moving everything - it saves time, money and risk, and you do not lose the information.
Is a SAP-to-Odoo migration a lift-and-shift?
No. It is a redesign, not a copy. You rebuild processes in Odoo rather than replicating SAP configuration one to one. Precisely because you leave the SAP complexity behind, it gets lighter.
What does switching cost compared to staying on SAP?
In our practice the total five-year cost of an Odoo switch for an SMB is far lower than an S/4HANA migration - often by a factor of 2 to 3, depending on scope. The TCO table above puts both side by side as an indication.
What goes wrong most often in an ERP switch?
Dirty data cleaned up too late, no internal process owner, and a big-bang go-live where a phased approach was safer. All three are avoidable, and that is where most of our work sits up front.
When are you better off staying on SAP?
When you are genuinely enterprise: dozens of legal entities, multinational consolidation and heavy compliance, with the budget and team to run SAP well. Then S/4HANA offers depth a lighter platform does not have out of the box.
Thinking about a switch?
We will think along, with no strings attached, about whether and how a move from SAP to Odoo pays off in your situation - even if that means you are better off staying put. Talk through your situation with us and we will hold your process honestly against both sides.
Read more: The best SAP alternatives, honestly scored · Odoo vs SAP: the full comparison · Why switching to S/4HANA isn’t always the right call