The overall migration project will time time to complete, however one of the big advantages of Azure Integration Services will be the ability to perform a phased migration where you can iterate over the individual interfaces implemented in BizTalk and migrate them one at a time.  There may be cases where you need to group interfaces but a phase approach is likely to be better than a big bang approach.  It will also reduce your risk.

The timelines below are indicative and will depend heavily on your BizTalk implementations complexity.

Timeline

High-Level Migration Roadmap

Phase 1 – Initiation & Viability (0–3 months)

• Define vision and success criteria.

• Assess current BizTalk landscape (applications, orchestrations, dependencies).

• Build business case and ROI model.

• Conduct feasibility / proof of concept with a simple integration in Azure.

• Secure sponsorship and funding.

Phase 2 – Planning & Design (3–6 months)

• Develop migration strategy (phased, hybrid, or big bang).

• Map BizTalk components → Azure Integration Services equivalents.

• Define architecture, governance, security, and cost management approach.

• Establish PMO oversight, risk register, and change management plan.

• Train team / begin capability uplift.

Phase 3 – Pilot Migration (6–9 months)

• Select low-risk, non-business-critical integrations for pilot.

• Build CI/CD pipeline and monitoring framework in Azure.

• Validate performance, security, and cost assumptions.

• Gather feedback from business stakeholders.

• Refine migration playbook & templates.

Phase 4 – Phased Rollout (9–18 months)

• Migrate workloads in waves (e.g., EDI, API services, partner connections, batch jobs).

• Run BizTalk and Azure in parallel until stable.

• Apply FinOps governance to manage cloud consumption.

• Regular checkpoint reviews with PMO & business owners.

Phase 5 – Decommission & Optimization (18–24 months)

• Retire BizTalk infrastructure and associated SQL servers.

• Reclaim licensing and hardware costs.

• Optimize Azure environment for performance, security, and cost.

• Transition into steady-state support model (CoE or MSP).

• Explore innovation: AI, analytics, event-driven, SaaS integrations.