.NET 6 is Out of Support – How to Safely Migrate to .NET 8

.NET 6 approaches its end of support. So, many enterprises that run mission-critical workloads should plan their next steps. Luckily, .NET 8 is an LTS version. Microsoft worked on its performance, cloud-native features, and also improved developer productivity compared to previous versions. If the company migrates to .NET 8, it will secure its applications and ensure their long-term maintainability. 

In this article, we are talking about why and when you should upgrade, what the key steps of the migration process are, and we are giving a practical checklist to ensure a smooth transition. For tailored assistance, explore our .NET migration services.

Key Takeaways from the Article

• .NET 6 reached end-of-support in November 2024.
• .NET 8 is an LTS release with extended support.
• Migration is a necessary step for improved performance, security and cloud readiness.
• A structured approach reduces risks during migration.

Where and How to Start Your Migration

First of all, as always, you should understand the scope of migration: which applications and services are in play – the more details you understand, the better. Also, think about what success will look like – what are the criteria? Performance baselines, SLAs, and compliance requirements are just some of the examples. 

At early stages, involve key stakeholders: product owners, developers, security teams, and DevOps engineers. Clarity allows for reducing risks later.   

Why Upgrade to .NET 8 LTS for Mission-Critical Applications

Here’s the list of reasons why migration to .NET 8 from .NET 6 is an effective solution:

• Long-Term Support (LTS). Unlike .NET 6 or .NET 7, .NET 8 will receive security updates until 2026.
• Performance Gains. Ahead-of-Time (AOT) compilation improves startup times and reduces memory footprint.
• Container and Cloud Readiness. Smaller container images, better orchestration, and Azure optimizations ensure faster releases and more resilient workloads.
• Security. Regular fixes and improved observability help maintain compliance.
• Modern Developer Experience. Enhanced APIs, EF Core 8 improvements, and cross-platform support which give faster feature delivery and a wider deployment range. These things matter both to CTOs and dev teams.

Decision Matrix: When to Move from .NET 6 to .NET 8

Scenario	Recommendation	Notes
Running mission-critical production apps	Migrate now	Ensure security, support, and SLAs.
Apps with medium SLA and active updates	Defer with guardrails	Patch, containerize, and prepare dependencies.
Legacy apps with a limited roadmap	Partial re-platform	Upgrade core services; wrap non-critical components in compatibility layers.

Steps to Safely Migrate from .NET 6 to .NET 8

Let’s break down the migration process into steps – we will explain what to do and how to do that. 

#1 Prepare your development environment

Ensure that your local and CI environments support .NET 8. How?

• You should install .NET 8 SDK from the official page.
• Update IDEs (especially Visual Studio 2022 (17.8 or later)).

As a result, developers will be able to build, run and test project files locally.

#2 Audit codebase and dependencies

The next step is to check all NuGet packages, SDKs, and third-party dependencies for .NET 8 compatibility. 

What will help?

• Run dotnet list package –outdated.
• Review third-party libraries in GitHub/Docs.

In the end, you should have a dependency status report and blockers identified.

#3 Update SDKs, Target Framework, CI/CD Pipelines, and containers 

So, all the files and pipelines should be changed to .NET 8. This is how:

• Go to .csproj:
  <TargetFramework>net8.0</TargetFramework> 
• Also, update CI/CD runners and container base images.

#4 Update ASP.NET Core hosting and APIs

To run your web apps and APIs with .NET 8 runtime, adopt new hosting solution and middleware updates. To do that, replace deprecated APIs and leverage minimal APIs and middleware improvements. 

#5 Manage breaking changes without breaking releases

When you upgrade from .NET 6 to .NET 8, Microsoft introduces breaking changes. This means some old APIs, behaviors, or defaults no longer work the same way. So, you should mitigate the impact of .NET 8 breaking changes. 

• Review .NET 8 breaking changes
• Use feature flags and backward-compatibility layers.

When done right, you should have stable releases without production downtime.

#6 Roll out and monitor 

When you move from .NET 6 to .NET 8, the code may work in test, but production traffic is always the real test. So, you need to deploy safely with controlled rollout strategies.

• Use blue-green deployments, running two production environments side by side – Blue, which is current .NET 6, and Green, which is .NET 8. When it is stable, flip traffic to Green, but if anything breaks, roll back to Blue.
• Release via canary users, deploying the .NET 8 version to a small percentage of users (say 5%). Monitor how they behave, and if everything looks good, expand to 25%, 50% and then all 100%. 
• Monitor performance and error metrics. Track such metrics as latency, throughput, and memory usage. Compare before & after baselines to ensure that .NET 8 improves performance.

This is how you can minimize risks when going into production.

.NET 6 to .NET 8 Migration Checklist

Automated tests and observability are in place
Dependencies reviewed and compatible
Security review complete
CI/CD and container images updated
Environment parity confirmed (dev, staging, prod)
Release and rollback plan defined
Success metrics and stakeholder sign-off 

Useful Resources for Migration

These official Microsoft resources might be helpful:

https://dotnet.microsoft.com/en-us/download/dotnet/8.0 – official download page for .NET 8 SDKs, runtimes, and installers. 

https://learn.microsoft.com/en-us/dotnet/core/whats-new/dotnet-8/overview – here, you will find documentation on new features and improvements in .NET 8. 

https://learn.microsoft.com/en-us/previous-versions/dotnet/ – archive of older .NET releases. Use it to compare version differences, check support status, or reference legacy API documentation during migration. 

How Softacom Can Help with Your Migration

If you want to migrate critical applications, you need planning and execution expertise. Softacom has been helping companies with migration and modernization for years. We can help reduce risks, optimize costs, and ensure business continuity during migration. Request your free .NET modernization consultation.

Drawing the Line

If you are planning migration to .NET 8, be ready to spend time and effort. But the right approach can make the process straightforward. Moving from .NET Framework or .NET Core will require a lot more resources. But .NET 6 to .NET 8 migration can be done with confidence when there is a plan, testing, and the right expertise.