Dynamics NAV and GP replacement
Leaving NAV or GP? Move to Odoo, not just the next upgrade.
Microsoft's route for NAV and GP customers is Business Central, which is a new implementation in its own right. If you are re-implementing anyway, compare it with Odoo: one ERP for finance, sales, inventory, manufacturing, CRM and service, with your data reconciled through trial migrations.
- Official Odoo Partner
- Trial migrations before cut-over
- ISO 27001 certified
- UK team in Northampton
In one sentence
What does replacing NAV or GP with Odoo mean?
It means moving your finance and operations from Dynamics NAV or GP into Odoo instead of re-implementing on Business Central. Master data, open entries and balances are extracted, cleansed, mapped and loaded into Odoo, and years of customisations are reviewed so most are replaced by standard features.
- 01Why now
- NAV 2018 extended support ends in January 2028; GP mainstream support ends in December 2029.
- 02What moves across
- Chart of accounts and dimensions, customers, vendors, items, open entries, balances and chosen history.
- 03Customisations
- Each one reviewed: kept as configuration, rebuilt as a clean module, or retired.
- 04Typical timeline
- A few months in phases, depending on modules, add-ons and how much custom code you rely on.
Why it matters
NAV and GP support is running out, and the dates are public.
Microsoft has published end dates for both products. Every year of delay shortens the runway for a calm, well-tested move.
extended support ends for Dynamics NAV 2018, the last NAV release
Microsoft lifecycle →Dynamics GP subscription licences stopped being sold to new customers
GP lifecycle summary →end of mainstream support, tax updates and service packs for Dynamics GP
GP lifecycle summary →final security updates for Dynamics GP end
GP lifecycle summary →Dates from Microsoft's lifecycle policy and a Microsoft partner's summary of the GP announcement. Dates can change, so check your version with your provider.
Migration risks
What is keeping you on NAV or GP?
Most firms stay on NAV or GP for the same few reasons. Every one of them can be planned for.
None of these is unusual. Each one is a planning task, and we show you the order to tackle them in.
Years of custom code
NAV or GP was customised by a partner who has since moved on.
→ Fix: a customisation review, with most needs met by standard Odoo and the rest rebuilt cleanly.
Dimensions everywhere
Reporting relies on dimensions and analysis codes built up over years.
→ Fix: dimensions mapped to Odoo analytic plans and tested against your management reports.
ISV add-ons
Warehouse, EDI or reporting add-ons from third parties sit on top.
→ Fix: each add-on matched to an Odoo app, connector or integration before build starts.
Business Central feels like the default
The obvious route is a move within Microsoft, without comparing alternatives.
→ Fix: an honest comparison of Odoo and Business Central on scope, licences and fit.
Fear of losing history
Years of ledger detail sit in a SQL database nobody else can query.
→ Fix: a history strategy, with the old database archived and still reportable.
We cannot afford downtime
A single untested cut-over leaves no room to learn how long loads really take.
→ Fix: timed trial migrations and a rehearsed cut-over runbook.
After the move
From an ageing NAV or GP to a supported, modern ERP.
See where your data lives today, then flip to see it after the move to Odoo.
TodayYour systems today
A move to Business Central is a new implementation too. Make it the right one.
After migrationNAV or GP data, landed in the right Odoo apps
ContactsCustomers, suppliers
SalesOpen orders
PurchaseOpen POs
InventoryProducts, stock
AccountingBalances, open items
DocumentsArchive linksHow we migrate
Rehearse the move until cut-over is routine.
Within our SCALE method, migration runs as its own workstream with signed-off checkpoints. Data is profiled, cleansed and loaded into a test database several times before anything touches the live system.
Scope
Find out what you really have
CRMInventoryAccountingWe extract data from your current system and spreadsheets, then measure it: record counts, duplicates, blanks and inconsistencies. For upgrades, we review every custom and third-party module. You see the real picture before anyone commits to a date.
- Data quality report by object
- Inventory of every source system
- Custom and third-party module register
- Agreed list of what migrates
- History and archive decision
No surprises later about the state of your data or code.
3,412 records · 172 duplicatesCleanse
860 records · 41 missing VAT numbersCleanse
5,120 records · units checkedReady
1,486 records · aged debt matchesReady
38 found · 12 still usedDecide
Craft
Decide where every field belongs
CRMSalesAccountingEvery source field is matched to its Odoo equivalent, and original references are kept as external IDs so migrated records can always be traced back. Your data owners agree the cleansing rules; we apply them consistently.
- Field-by-field mapping document
- External IDs back to the source system
- Duplicate merge rules agreed
- Chart of accounts and tax mapping
- Import templates per object
A mapping your team understands and signs off.
Account: TRADE0412
Name: Trade Customer Ltd
Terms: 30 days EOM
VAT reg: GB 123 4567 89
Credit limit: 15,000
Build
Replace custom code with configuration
AnalyticsWhile data is cleansed, we configure Odoo: chart of accounts, analytic plans for your dimensions, approvals, warehouses and the flows your NAV or GP customisations used to handle.
- Customisation review and decisions
- Dimensions mapped to analytic plans
- Add-ons replaced by apps or connectors
- Management reports rebuilt
- Integrations retested end to end
A working Odoo your teams can test with their own data.
Assemble
Load, check and repeat
InventoryAccountingWe load the data into a test database, check it with your team, fix what is wrong and load again. Each trial is timed, so the real cut-over window is known long before go-live.
- At least two full trial loads
- Timed load runbook
- Exceptions log with owners
- User checks on real records
- Fixes applied at source or in rules
Go-live is a repeat of something that has already worked.
On plan
Owner: finance
Signed off
Launch
Prove the numbers, then switch
AccountingInventoryBalances, stock values and aged debt are reconciled line by line and signed off by your finance team. Then we follow the rehearsed runbook: freeze, final load, validation checks, and Odoo opens for business.
- Trial balance reconciled
- Aged debtors and creditors matched
- Stock quantities and values matched
- Go or no-go checkpoint
- Hypercare after go-live
A planned switch, not a leap of faith.
Exceptions by object trial 1 to trial 3
Screens show illustrative data. The exact steps depend on whether you are upgrading Odoo or moving to it from another system.
Odoo licence pricing
Which Odoo plan will you land on?
Moving to Odoo, or from Community to Enterprise, means choosing a plan. Your hosting and custom code decide which one fits. UK list prices, billed yearly, excluding VAT.
One App Free
£0/month
One app, unlimited users
- A single app on Odoo Online
- Unlimited users
- No custom modules
Fits a first, single-app step
Standard
£18/user/month
First 12 months, then £22
- All Odoo apps
- Odoo Online only
- No custom Python modules, Studio or external API
Fits standard processes with no custom code
Custom
£32/user/month
First 12 months, then £41
- Everything in Standard
- Studio, multi-company and external API
- Odoo.sh or on-premise for custom modules
- Odoo.sh hosting charged extra
Fits migrations that keep custom code
All plans include Odoo’s unlimited functional support, maintenance and upgrades of standard features. Maintenance of custom code is not included in any plan. Prices checked on odoo.com/pricing in October 2026, per user per month billed yearly, ex VAT. Always check the vendor page before you buy. Migration work is quoted separately. See our Odoo hosting options guide.
Quick check
Is it time to leave NAV or GP?
Tick the statements that are true for your business today.
0/6
Why Thoughtlogik
Why trust Thoughtlogik with your data?
We are a Northampton-based Official Odoo Partner with a delivery team in Coimbatore, India. Our consultants run workshops about your processes, not software jargon, and we stay with you after go-live.
ISO 27001 certified
Customer, supplier and financial data is handled under our certified information security management system.
Rehearsal, not guesswork
We never treat go-live as the first real load. Timed trial migrations show exactly what cut-over involves.
Finance-grade reconciliation
Balances, stock values and aged debt are reconciled and signed off by your finance team before go-live.
Odoo developers in-house
Our developers publish Odoo apps and port custom modules properly, then keep them healthy through Thoughtlogik Shield for Odoo.
How we deliver
SCALE: five phases, clear deliverables.
Scope
Define success and lock the scope
- Success criteria and KPIs
- Approved requirements and process maps
Craft
Design the right solution first
- Solution design blueprint
- Integration and data migration plan
Assemble
Configure, integrate and test
- A configured, working system
- Tested automations and integrations
Launch
Train, go live and stabilise
- Trained, confident users
- Go-live with hypercare
Evolve
Optimise and keep improving
- Continuous improvement roadmap
- Regular health checks
FAQs
NAV and GP to Odoo: common questions
Cannot see your question? Our UK consultants are happy to talk it through.
When does support end for Dynamics NAV and GP?
Microsoft's lifecycle policy lists January 2028 as the end of extended support for Dynamics NAV 2018, the last NAV release. For Dynamics GP, Microsoft has announced the end of mainstream support in December 2029 and of security updates in April 2031. Check your exact version with your current provider.
Do we have to move to Business Central?
No. Business Central is Microsoft’s successor, but moving to it is still a new implementation. If you are re-implementing anyway, compare it with Odoo on scope, licence cost and fit. See our Odoo vs Business Central comparison.
What happens to our NAV or GP customisations?
We review each one. Many are covered by standard Odoo features or configuration, some are rebuilt as clean Odoo modules, and some are no longer needed. You get the list and the decisions before build starts.
Can Odoo handle our dimensions and analysis codes?
Yes. Odoo analytic accounting supports multiple analytic plans, so dimensions such as department, project or region are mapped and tested against your management reports.
How much history should we bring across?
Usually opening balances, open entries and one or two years of summary history. The old NAV or GP database can be kept read-only for reference and audit.
Can Odoo run on-premise like NAV?
Yes. Odoo runs on Odoo Online, on Odoo.sh or on your own servers, so you can choose cloud or on-premise hosting. See our Odoo hosting options.
How long does a move from NAV or GP to Odoo take?
Most run over a few months in phases, depending on modules, add-ons, integrations and data quality. We give you a timeline after a free scoping call.
Do you also support Odoo after go-live?
Yes. Our UK team provides ongoing support and upgrades through Odoo support UK.
Keep exploring
Related Comparisons and migration guides
Start your project
Ready to move off NAV or GP?
Tell us which version you run, what has been customised and when your support ends. An Odoo consultant will come back within one working day with a suggested approach.
- Free, no-obligation consultation
- Official Odoo Partner, ISO 27001 certified
- Clear migration plan before any work starts
Running NAV or GP?Talk to a UK Odoo consultant
Book a free call