Odoo Implementation Timeline: How Long a Rollout Really Takes
Most Odoo implementations for a mid-market company take 12–20 weeks. Here is where every one of those weeks goes, what shortens them, and what quietly doubles them.
Typical duration by project size
| Project profile | Elapsed time |
|---|---|
| Small (5–20 users, 2–4 modules) | 6–10 weeks |
| Mid-market (20–75 users, 5–8 modules) | 12–20 weeks |
| Complex (75+ users, MRP, multi-entity, integrations) | 5–9 months |
| Project rescue (existing broken rollout) | 2 weeks audit + 6–14 weeks remediation |
Budget ranges for each profile are broken down in our Odoo implementation cost guide.
The six phases, week by week
Phase 1 — Discovery & process mapping
Weeks 1–2Workshops per department, current-state process maps, module scope, integration list, and a written gap register. Nothing gets configured until the gap register is signed off.
Phase 2 — Configuration & prototype
Weeks 3–6Company, chart of accounts, taxes, products, warehouses, and workflows configured in a staging database. Key users see a working prototype with their own sample data by the end of week 6.
Phase 3 — Data migration
Weeks 5–9 (overlaps)Master data first (partners, products, BoMs), then balances and open transactions. Two dry runs minimum, with reconciliation reports compared against the legacy system.
Phase 4 — Custom development & integrations
Weeks 6–11Only the gaps that survived Phase 1 scrutiny: custom reports, e-invoicing or tax connectors, payment gateways, EDI, or shop-floor screens. Each item is estimated and approved separately.
Phase 5 — UAT & training
Weeks 10–13Scripted user-acceptance tests per role, defect triage, and role-based training with your own data. Go-live is gated on UAT sign-off, not on the calendar.
Phase 6 — Go-live & hypercare
Weeks 13–16Cutover at a period end, opening balances loaded, then 2–4 weeks of hypercare with same-day response while users settle and reports are validated.
Why timelines slip
Master data is dirty and nobody owns cleaning it — the single most common cause of slippage.
Scope grows during configuration because gaps were never written down in Phase 1.
Key users have no allocated project hours, so UAT and training slip week after week.
Integrations depend on a third party whose API access or sandbox takes weeks to obtain.
Go-live is scheduled mid-period, forcing manual opening balance corrections.
If a rollout has already slipped badly, the fix is an audit before more configuration — see the five signs a project needs rescuing and our project rescue service.
How to compress the timeline safely
- Phase the go-live: finance and sales first, manufacturing or e-commerce in phase two.
- Adopt standard Odoo behaviour wherever a process is not a competitive advantage.
- Assign one internal data owner per master-data set before week one.
- Freeze scope after the gap register is signed; queue everything else for post-go-live.
- Book key users for two half-days a week and protect that time.
Want a dated plan for your rollout?
We will map phases, owners, and a realistic go-live date for your scope.