The first question in most BizTalk migration conversations is simple: what happens to everything we already built? Less gets thrown away than most teams expect, but nothing moves without a decision.
Where each piece goes
| BizTalk | Azure Integration Services |
|---|---|
| Receive ports and locations | Logic Apps triggers and API Management |
| Send ports | Logic Apps actions and connectors |
| Orchestrations | Logic Apps workflows |
| MessageBox | Service Bus topics and Event Grid |
| XSLT maps | Logic Apps XML transforms and Data Mapper |
| XSD schemas | Reused in Logic Apps or an Integration Account |
| Pipelines and custom components | Built-in XML operations and Azure Functions |
| Business Rules Engine | Azure Logic Apps Rules Engine |
| Trading partners, EDI and AS2 | Integration Account |
| BAM and message tracking | Azure Monitor and Application Insights |
| SSO database | Azure Key Vault and managed identities |
What usually carries over easily
Schemas and maps are often the easiest assets to reuse, because they are standard XSD and XSLT. Test them anyway: a map that relies on custom code or scripting will need extra work.
What needs the most thought
Orchestrations. Long-running processes, correlation and compensation logic rarely translate line by line. Treat each one as a chance to ask what the process needs today.
Custom pipeline components and helper classes. These often hold undocumented business rules. Find out what they do before you rewrite them.
Publish and subscribe. In BizTalk, subscriptions can be implicit in the MessageBox. In Azure, you design topics and filters explicitly, which is clearer but needs planning.
Rebuild or re-platform?
Each interface needs its own answer. Simple, stable interfaces can often be re-platformed quickly. Complex ones with years of workarounds may be cheaper to rebuild once you understand what they should do.
You don't have to decide everything up front. Our BizTalk end-of-support plan starts with an inventory and one low-risk pilot, which shows what your own estate needs.