SL Dynamics vs Business Central: when to move

SL Dynamics is Microsoft Dynamics SL, the on-premises project and financial ERP many teams still call Solomon. For the 2018 release, Microsoft's Lifecycle FAQ sets the end of mainstream support at January 9, 2024 and the end of extended support at July 11, 2028, and it points customers to Dynamics 365 Business Central online. Extended support still includes security updates and paid support. New features and non-security updates sit outside that phase under Microsoft's Fixed Lifecycle Policy. If your database is on SQL Server 2016, extended support for that SQL version ended July 15, 2026.

Use January 9, 2024 and July 11, 2028 in board materials. The product lifecycle page prints January 10, 2024 6:59:59 AM PT and July 12, 2028 6:59:59 AM PT. The June 5, 2025 blog and the SL directory still say mainstream ended July 11, 2023. Prefer the FAQ.

What the Dynamics SL end of life dates are

Dynamics SL 2018 follows the Fixed Lifecycle Policy. The product page records a start of May 1, 2018, 8:00:00 AM PT. Mainstream support is the phase that included incident support, security updates, and the ability to request non-security updates. That phase is over. The FAQ states Microsoft moved the mainstream end from July 11, 2023 to January 9, 2024. The product table's January 10, 2024 6:59:59 AM PT stamp is the policy clock for that same cutoff.

Extended support runs through July 11, 2028 on the FAQ and the June 5, 2025 blog. The product table shows July 12, 2028 6:59:59 AM PT. Under the Fixed Lifecycle Policy, extended support includes paid support and security updates at no additional cost. Microsoft will not accept requests for warranty support, design changes, or new features in that phase. Non-security updates are not part of extended support.

Business Central online is a different product on the Modern Lifecycle Policy. Its lifecycle listing starts November 1, 2016, and the retirement field is shown as In Support. Microsoft's named path off SL is Business Central online, documented in the SL cloud-migration guides and repeated in the June 2025 blog. Dynamics 365 Project Operations is a separate license, not the target of that tool.

Versions older than SL 2018

Dynamics SL 2015 mainstream support ended January 15, 2020, 6:59:59 AM PT, and extended support ended January 15, 2025, 6:59:59 AM PT, per the SL 2015 lifecycle page. That page says a customer can move to Dynamics 365 Business Central, and that an older version must first be upgraded to Dynamics SL 2018 and then to Business Central. The cloud migration tool accepts Dynamics SL 2015 or later, so a 2015 database can be a technical source only after you meet the SQL prerequisites. If you are still on a release older than 2015, budget the upgrade to 2018 as its own project before anyone talks about a cloud cutover.

The directory describes SL as ERP for project and financial management and names construction, government contracting, professional services, engineering, and nonprofit. That industry list is why a generic cloud pitch fails controllers: the books are organized around projects, tasks, and subaccounts.

Which deadlines hit before July 2028

Three clocks run at once. Mixing them is how a stay-put plan looks safe on a slide and tight on the server.

• July 15, 2026 (What changes: SQL Server 2016 extended support ended. Extended Security Updates are listed for three years after that, through July 17, 2029. · Where Microsoft states it: SQL Server 2016 lifecycle)
• July 11, 2028 (What changes: Dynamics SL 2018 extended support ends on the FAQ. Security updates stop with it. The product-page stamp is July 12, 2028 6:59:59 AM PT. · Where Microsoft states it: Lifecycle FAQ and Dynamics SL 2018 lifecycle)
• January 15, 2030 (What changes: Service plan coverage ends. That date is the last day to license more perpetual users on existing systems. SPLA subscription use is expected to end. · Where Microsoft states it: June 5, 2025 Dynamics 365 blog)

A live SL database still on SQL Server 2016 is past that platform's extended support even while SL 2018 itself remains in extended support until 2028. The migration prerequisite is SQL Server 2016 SP1 or later, compatibility level 130 or higher, TCP/IP enabled, and SQL authentication with sysadmin on the server and db_owner on the database. Meeting the minimum for the tool is not the same as running a supported database engine. If you need Extended Security Updates to keep SQL Server 2016 patched through 2029, get that quote beside the Business Central quote so the stay path has a real number.

The June 2025 blog says "These dates may seem far off, but full cloud migration is not something that can be accomplished overnight". The same post says "You may be wondering how the transition to Business Central will impact your workflows, operations, and reporting." The reporting impact shows up in subaccounts, project history, and open periods, which the next sections cover. Teams comparing notes with a sister company on Great Plains can use the same commercial pattern on our Dynamics GP end of life migration options page. GP is a different product with its own data map.

How Microsoft Dynamics SL differs from Dynamics 365 Business Central

SL is the on-premises application you patch, back up, and keep on a SQL Server you operate. Business Central online is the cloud application Microsoft names as the destination, with Microsoft running the service under the Modern Lifecycle Policy. A public post is titled "Dynamics SL to Business Central Migration Strategies". The names sit in the same Microsoft family, and the documented path is a data migration into a new Business Central company. There is no switch that turns an SL company into a Business Central company.

License shape changes with the product. As of October 2026, Business Central is priced per user per month, paid yearly, on Microsoft's price list below. Project Operations, at USD 135 per user per month paid yearly, is a different Dynamics 365 app. It is not the documented target of the SL cloud migration tool. If a proposal mixes Project Operations users into the SL replacement license count, separate that line and ask which system will hold the general ledger.

Business Central's own project features cover a defined set: projects and tasks, resource scheduling and prices, time sheets, budgets versus actual usage, project supplies on purchase orders, customer invoicing at completion or on a schedule, and work-in-process posting. Documented WIP methods include Cost Value, Cost of Sales, Sales Value, Percentage of Completion, and Completed Contract, on the project management and WIP methods pages. That is enough for many professional services firms that bill time and recognize revenue on percent complete or completed contract. It is a redesign for firms whose SL books depend on allocation methods, burden rates, or government-contract ceilings. Have each bidder show those calculations on your projects before you treat the two systems as equivalent. We do that design work with firms in implementation for professional services.

What project accounting moves, and what you rebuild

This is the point where SL migrations get expensive. From the Project Controller module, Microsoft's tool migrates master records only: projects in Active or Plan status, tasks in Active status, and resources (project employees or other resources) in Active or On Hold status, based on configuration. The data-migrated article does not list project cost transactions, allocations, or WIP history as live Business Central project entries.

Read that as an opening trial balance for jobs. A project subledger would include cost history, and this load stops before that history. A project in a completed status is outside the status list above. Timecards already posted in SL do not become Business Central time sheets. Allocation results do not become live project ledger entries. If your bank, your auditor, or a contracting officer expects to drill from a current WIP figure back through last year's cost detail inside the new system, that drill path is new work. Read-only snapshot tables cover historical GL, receivables, payables, sales orders, purchase receipts, and inventory transactions (SL Hist. GLTran, APDoc, SOHeader, and others). Project cost, allocations, posted timecards, and WIP history are not among them. Archive those items from SL, or rebuild the ones you still need to post.

What you can keep using on day-to-day jobs

After go-live, Business Central can hold the job structure you rebuild: tasks, resource prices, time sheets, a budget, purchase orders for project supplies, and invoices on completion or on a schedule. Percentage of Completion and Completed Contract are both documented WIP methods, so a firm that already thinks in those two policies has a place to configure them. The configuration still has to be proven on your contracts. A cost-plus job with a ceiling, a rate cap, and a funding source is a design session, not a checkbox on the migration wizard.

Ask bidders to split the quote. One line is the master load the tool performs. The next line is the project model: which jobs are reopened, which cost categories exist, how time hits a job, and how WIP posts at month-end. A third line is history: how many years sit in snapshot tables, and which reports read them. Firms that accept a single data-migration line usually discover the project history in testing.

What the Dynamics SL to Business Central tool copies

The built-in cloud migration tool copies data with Azure Data Factory from the on-premises SQL Server database into the Business Central online database. SL stays the system of record until migration is completed. Any existing data in the target Business Central company is overwritten. Microsoft's overview says not to run cloud migration against a Business Central production environment that is already in use. Rehearse in a sandbox. You can rerun replication until the data upgrade. After a successful data upgrade, replication from an earlier version must not be run again.

The Cloud Migration Setup guide is supported only for the United States, Canada, the United Kingdom, and Australia. A US company and a Canadian company both sit inside that supported list. A subsidiary on a chart the guide does not cover does not, and that company needs another load method.

Before replication, Microsoft expects you to run the Dynamics SL Analysis and Repair tools from the microsoft/BCTech GitHub samples. The analysis report lists SL version, SQL version, modules in use, and master and transaction record counts. The repair tool validates data and includes some automated fixes. Those counts are the right attachment to a proposal. A bid that never asks for them is guessing at volume.

Masters, balances, and the open-item rule

Data the tool can bring includes company setup, fiscal periods (as accounting periods), tax groups (as tax areas), inventory sites (as locations), account, customer, vendor, and item masters, open customer and vendor document amounts, account balances by period, and configurable history. If Oldest GL Year is left blank, all years are migrated. Historical years come over as open accounting periods and must be closed in Business Central. Leaving the year blank feels complete until someone has to close a decade of periods in the new ledger. Set the oldest year on purpose, then archive anything older outside the tool.

Open receivables and payables move at the remaining balance, not the original document amount. Microsoft's case: a USD 1,000 invoice with USD 400 remaining is created in Business Central as a USD 600 invoice. Customer and vendor posting groups created by the tool are named SL. Inactive customers, vendors, and discontinued items are excluded unless the inactive-record switches are turned on. Turn those switches on only when you have a reason to carry inactive names into the live company. Otherwise they clutter apply-to lists.

For a selected year, vendor 1099 amounts are totaled by vendor and box, then wash invoices and payments are posted so the 1099 box is populated without changing GL balances, as described in Configure Dynamics SL company migration. Pick the year you still need to report. Confirm the wash batch in the sandbox before anyone files from Business Central.

Inventory moves with the cost valuation method set in Dynamics SL at migration time, plus quantity on hand by location and serial or lot information if tracked. Historical GL, receivables, payables, sales orders, purchase receipts, and inventory transactions can be stored as read-only snapshot tables (SL Hist. GLTran, APDoc, SOHeader, and others), not as live Business Central ledger entries. Snapshot scope is limited by Oldest Snapshot Year. An auditor who wants a 2022 vendor bill will open the snapshot, not the Business Central vendor ledger.

Subaccounts become dimensions

Dynamics SL subaccount segments become Business Central dimensions. When there is more than one subaccount segment, the migration configuration requires you to pick which segments become Global Dimension 1 and 2. Remaining segments become shortcut dimensions 3 to 8. Global dimensions are the ones that show on documents and in more reports. Choose the two segments managers filter on every week, often department and project or department and location. The rest remain available, with a narrower role. Print a subaccount segment list before configuration and mark the two that must be global. Changing that choice after history is loaded is a second migration.

• Chart, customers, vendors, items, sites, tax groups, fiscal periods: Live setup: accounts, customers, vendors, items, locations, tax areas, accounting periods
• Open AR and AP: Live documents at the remaining balance
• GL balances by period: Balances; historical years arrive open and must be closed
• Subaccount segments: Global Dimensions 1 and 2, then shortcut dimensions 3 to 8
• Project Controller: Masters only, and only in the statuses named above
• Older GL, AR, AP, orders, receipts, inventory transactions: Optional read-only snapshot tables, limited by Oldest Snapshot Year
• 1099 for a selected year: Wash invoices and payments that fill the box and leave GL balances unchanged

What Business Central licenses cost in the US

Microsoft publishes no services price and no fixed duration for an SL migration. Duration varies with data volume, SQL Server configuration, and connection speed. The dollars Microsoft does publish are licenses. As of October 2026, the US Business Central price list shows:

• Essentials (Price: USD 80 per user per month, paid yearly · What the page says: Base plan. Copilot is included on the base plans.)
• Premium (Price: USD 110 per user per month, paid yearly · What the page says: Adds service management and manufacturing to Essentials.)
• Team Members (Price: USD 8 per user per month, paid yearly · What the page says: Lower-priced user.)

The pricing page text does not assign project accounting to Essentials only or to Premium only. Do not let a proposal force Premium solely because you run projects. Premium is the plan Microsoft describes as adding service management and manufacturing. If you do not need those, price full users on Essentials and confirm on a formal quote that the project pages you need are in that plan. The Canadian price list, as of October 2026, is CAD 108.50 for Essentials, CAD 149.20 for Premium, and CAD 10.90 for Team Members, per user per month, paid yearly, plus applicable tax. This article's worked math stays in US dollars.

Assume 18 people need a full user and 12 people need Team Members for approvals and light entry. The other staff do not get a license in this sketch. At Essentials, 18 times USD 80 is USD 1,440 per month. Twelve Team Members at USD 8 add USD 96. The license total is USD 1,536 per month, or USD 18,432 per year at the yearly billing basis. The same 18 full users on Premium would be 18 times USD 110, which is USD 1,980, plus USD 96, which is USD 2,076 per month or USD 24,912 per year. Project Operations for those 18 people at USD 135 would be USD 2,430 per month, or USD 29,160 per year, and that figure does not include a Team Member price because the Project Operations page cited here does not list one. None of these totals is an implementation fee.

One publisher, Top Dynamics Partners, on a page last updated June 19, 2026, estimates that an SL to Business Central migration typically takes 3 to 6 months and costs USD 40,000 to USD 200,000 for mid-market companies. The same page prints bands of USD 40,000 to USD 90,000 for companies it labels at USD 5 million to USD 50 million of revenue, USD 125,000 to USD 270,000, and USD 340,000 to USD 730,000 or more for revenue of USD 500 million or more. The page says to add 15 to 25 percent for internal labor. Those figures bundle implementation labor, ETL, testing, training, and first-year licensing on that site's method. Treat them as that site's estimate. Microsoft publishes no services price, and the range is not our fee.

On the USD 40,000 low end, 15 percent internal labor is USD 6,000 and 25 percent is USD 10,000. On the USD 200,000 headline high end, 15 percent is USD 30,000 and 25 percent is USD 50,000. That internal time is your controllers reconciling the USD 600 open invoice, closing historical periods, and signing off WIP. It does not disappear if the partner fee is fixed.

Tax updates while you stay

While a customer is active on an Enhancement Plan or Software Assurance, Microsoft provides tax and regulatory releases that it makes generally commercially available. The Lifecycle FAQ says those updates for supported Dynamics products are released generally each fiscal year, or as needed, for software in the Mainstream Support phase. Mainstream support for SL 2018 has ended, so ask whoever holds your Enhancement Plan which tax and regulatory releases you can still apply. Microsoft publishes a Dynamics SL 2023 year-end update supported on Dynamics SL 2018 through Dynamics SL 2018 CU10, and it has also published a 2022 year-end update for SL 2018 through listed cumulative updates. Put which tax year you can still update on the stay-or-go checklist beside the July 2028 date. Ask your reseller for the SL renewal quote in writing, and compare that number with the Business Central license math above.

When an Odoo path is worth pricing

Odoo is a separate quote. Nothing in Microsoft's SL migration docs loads an SL database into Odoo, and Odoo's price pages do not offer that load either. You would design the opening balances, the project structure, and the history archive as a fresh implementation.

As of October 2026, the Odoo US pricing page shows two monthly figures for the Standard plan, USD 31.10 and USD 38.90 per user per month, and a struck figure near USD 24.90. The page does not label which of the two monthly figures is the annual commitment. A footnote says the discount is valid 12 months for the initial users ordered. Standard includes all apps on Odoo Online. Hosting, maintenance, and support are included. Implementation is not. The Custom plan shows USD 61.00 and USD 76.20 per user per month, with a struck figure near USD 49.00. Custom includes Odoo Online, Odoo.sh, or on-premise, Studio, multi-company, and an external API. Odoo.sh hosting is extra.

Using the same 18 full users, Standard at USD 31.10 is USD 559.80 per month and at USD 38.90 is USD 700.20 per month. Per year those are USD 6,717.60 and USD 8,402.40 before any discount footnote. That is lower than the Essentials total of USD 1,440 per month for those 18 users. The Odoo figure includes the app set on that per-user price. A Light User is listed at USD 8.90 per user. The page does not spell the billing period next to that figure, and the user is sold after an advisor review, not as self-serve checkout. One App Free at USD 0 is one app with unlimited users on Odoo Online. It is not a stand-in for a full project and finance company.

Odoo Success Packs for new customers, with the page's 15 percent off the first pack, list USD 493 for Starter (4 hours), USD 3,060 for Basic (25 hours), USD 5,950 for Standard (50 hours), USD 10,625 for Custom (100 hours), and USD 21,250 for Pro (200 hours). Returning customers are listed at USD 580, USD 3,600, USD 7,000, USD 12,500, and USD 25,000 for the same hour counts. Travel is extra, and extra monthly charges apply for maintenance of extra modules. The Pro pack is 200 hours. At the new-customer Pro price, that is USD 106.25 per listed hour. Those hours buy consulting time. An SL history migration needs its own scope on top of the pack. Two hundred hours will not carry multi-company SL history, a dimension redesign, and a rebuilt project model. Price Odoo licenses as the subscription, then price implementation as its own project. Our Odoo vs Dynamics 365 cost and fit comparison is the longer version of that price gap.

Odoo earns a look when you want all apps on one per-user fee, you can reopen projects from masters and balances, and you accept a designed conversion. Business Central earns the look when you want Microsoft's SL tool for the GL, open AR and AP, inventory quantities, and dimensions, and you are willing to rebuild project history beside that tool. Staying on SL earns the look when extended support through July 11, 2028 still covers your risk, SQL Server is on a supported branch or a priced ESU, you will not need new perpetual users after January 15, 2030, and the project model in SL still matches how you bill.

How to decide whether to stay on Dynamics SL

Stay when four checks are true at the same time.

1. You are on Dynamics SL 2018, with a cumulative update your tax process can live with, and you have a written answer on Enhancement Plan coverage.
2. SQL Server is newer than the 2016 branch, or you have priced Extended Security Updates through the window Microsoft lists to July 17, 2029.
3. You will not need additional perpetual users, and you do not depend on SPLA, after January 15, 2030.
4. Project history can remain in SL for the years you must defend, because you are not opening those jobs in a new system yet.

Move toward Business Central when any of those checks fail, or when the reporting you need next year depends on a feature extended support will not add. Microsoft will not take design-change or new-feature requests during extended support. If the gap is a new billing calculation, waiting until 2028 does not produce that calculation inside SL.

Move toward Odoo when the license comparison above is attractive and you have already accepted a from-scratch project model. If your auditor wants the Microsoft snapshot tables and the remaining-balance open items, Business Central's tool is the one that publishes that map. If your main pain is per-user ERP price and you have a small set of active jobs, put Odoo on the same requirements list and score both on the project rebuild and on the monthly fee.

For a single US professional services company, already on SL 2018 and SQL Server 2017 or newer, with active jobs that fit percent-complete or completed-contract billing, Business Central Essentials plus Team Members is the comparison we start with. The license sketch above is USD 18,432 per year before services, at October 2026 list prices, for 18 full users and 12 Team Members. Government contractors and firms with heavy allocations should expect the services line to dominate that license line, because the tool stops at project masters.

What to put in the first phase

Microsoft does not publish a project length. The 3 to 6 month range above is one site's estimate for a broad migration, and it mixes in first-year licenses. A first phase can be smaller than that whole journey if you define it as the books you will post in.

Our target for a first usable phase is 8 to 12 weeks. We run that phase with the Flectic Accelerated Delivery Framework. The target covers a defined first slice, such as one company, a chosen GL year range, open AR and AP, inventory quantities, and project masters, with history snapshots agreed up front. It is our planning target for that slice, and it covers that slice only.

A practical sequence:

1. Confirm the SL version. A release older than 2015 has to be upgraded to SL 2018 before cloud migration. An SL 2015 database can be a source once SQL Server 2016 SP1, compatibility level 130, TCP/IP, and the SQL login rights are met. SL 2015 extended support ended January 15, 2025.
2. Confirm SQL Server version, compatibility level 130 or higher, TCP/IP, and the SQL login rights the prerequisite page lists. If you are on SQL Server 2016, put the ESU decision in the same week.
3. Run the analysis report and attach the record counts to the statement of work. Run the repair tool in a copy and review what it changed.
4. Choose Global Dimension 1 and 2 from your subaccount segments. Set Oldest GL Year and Oldest Snapshot Year. Decide the inactive-record switches and the 1099 year.
5. Replicate to a sandbox. Reconcile the open AR and AP remaining balances, the GL by period, and the on-hand quantities. Close the historical periods in that sandbox once and record the steps.
6. List every Project Controller need the masters do not cover. Price that list as its own line before you set a go-live date.
7. Complete the data upgrade once. Stop posting in SL on a dated cutover. Do not rerun replication from the old version after that upgrade.

Code you pay for should be yours to keep, with the sandbox trail and the dimension map stored in your tenant. Ask for named consultants, hours per phase, and two references that moved project masters from a project-accounting system. Partner program tiers do not answer those questions. A Business Central implementation for a project firm leaving SL is scoped in those phases: discovery, configuration, the migration settings above, training, and support after you cut over. If you want the wider ERP engagement around process design and the first close, our phased ERP implementation work starts from the same record counts.

The decision is a calendar plus a data map. July 11, 2028 ends extended support for SL 2018. January 15, 2030 ends the commercial extras Microsoft listed for service plans, added perpetual users, and SPLA. SQL Server 2016 is already past extended support. The migration tool will carry your financial masters and open balances, and it will not carry Project Controller history as live jobs. Price licenses from the Microsoft list, price services as a separate scope, and book the call when you want those lines written against your own company.

How Flectic can help

Flectic implements Dynamics 365 Business Central for companies of 20 to 100 people in the US and Canada that are moving off on-premises Dynamics SL. Business Central covers operations and costing, including inventory, projects and jobs, with landed costs and work in progress. We work alongside your team through the first month-end close on the new system. Book a free discovery call with Flectic through our Dynamics 365 implementation service to plan the move before the Dynamics SL deadlines.

Sources

• Lifecycle FAQ - Dynamics, Microsoft, October 2026
• Dynamics SL 2018 - Microsoft Lifecycle, Microsoft, October 2026
• Fixed Lifecycle Policy, Microsoft, October 2026
• Dynamics SL 2015 - Microsoft Lifecycle, Microsoft, October 2026
• Explore migration options for Microsoft Dynamics GP and Microsoft Dynamics SL customers, Microsoft, June 2025
• Microsoft Dynamics SL Directory, Microsoft, October 2026
• SQL Server 2016 lifecycle, Microsoft, October 2026
• Dynamics 365 Business Central lifecycle, Microsoft, October 2026
• Cloud Migration Prerequisites for Dynamics SL, Microsoft, October 2026
• Dynamics SL migration to Business Central online overview, Microsoft, October 2026
• Dynamics SL Data Migrated to Business Central Online, Microsoft, October 2026
• Project management - Business Central, Microsoft, October 2026
• WIP methods, Microsoft, October 2026
• Dynamics 365 Project Operations pricing, Microsoft, October 2026
• Dynamics 365 Business Central pricing (US), Microsoft, October 2026
• Dynamics 365 Business Central pricing (Canada), Microsoft, October 2026
• Dynamics SL 2023 year-end update, Microsoft, October 2026
• Dynamics SL to Business Central migration guide, Top Dynamics Partners, June 2026
• Odoo pricing, Odoo, October 2026
• Odoo Success Packs, Odoo, October 2026
• Dynamics SL to Business Central Migration Strategies, Reddit, October 2026