Top Rated Silverlight to Blazor Migration Services
Compare Silverlight to Blazor partners. Real costs ($100K-$800K), timelines (4-12 months), WebAssembly vs Server strategies. 25+ firms analyzed.
- Market Rate
- $50 - $150 per component
- Typical Timeline
- 6-12 Months
- Complexity
- High
Updated: February 2026 · Based on 150 verified implementations · Author: Peter Korpak · Independent methodology →
Is Silverlight → Blazor the Right Migration?
Migrate if...
- → Silverlight plugin is blocked by all major browsers (Chrome, Edge, Firefox, Safari)
- → Application is inaccessible to users on modern browsers
- → Silverlight end-of-life (October 2021) makes security patching impossible
- → Team has C# expertise — Blazor WebAssembly/Server enables C# in the browser
Don't migrate if...
- ✗ Team wants to exit the .NET/C# ecosystem entirely
- ✗ Application is too complex for Blazor's current state (e.g., complex canvas rendering)
Alternative Paths
| Alternative | Why Consider It | Best For |
|---|---|---|
| Silverlight → React or Angular | JavaScript ecosystem — larger talent pool and component libraries than Blazor | Organizations without strong .NET/C# investment who want the largest frontend ecosystem |
| Silverlight → WPF (desktop-only) | Move to native Windows desktop if browser access isn't required | Internal enterprise tools that only need Windows desktop, not web access |
Why Organizations Migrate
- → Silverlight is effectively broken — modern browsers block plugin execution entirely
- → Blazor WebAssembly enables C# in the browser — preserves team's .NET investment
- → Application becomes accessible on all devices (mobile, tablet) for the first time
- → Eliminates IT support burden of managing Silverlight plugin compatibility workarounds
Market Benchmarks
150 Real Migrations AnalyzedWe analyzed 150 real-world Silverlight to Blazor migrations completed between 2022-2024 to provide you with accurate market intelligence.
Most Common Failure Points
Migration Feasibility Assessment
You're an Ideal Candidate If:
- App requires IE mode to run (Security risk)
- Team is already skilled in C#/.NET
- Rich client interactivity is required
Financial Break-Even
Migration typically pays for itself when current maintenance costs exceed $50k/year.
Talent Risk Warning
Low. C# skills transfer perfectly to Blazor.
Critical Risk Factors
According to Modernization Intel's analysis of 150 Silverlight to Blazor migrations, 4 risk factors are responsible for the majority of project failures. Each factor below includes the failure pattern and a validated mitigation strategy.
Risk 01 Plugin vs. WebAssembly Performance Gap
Silverlight ran as a native plugin with near-native performance. Blazor WebAssembly is 3-10x slower for compute-intensive tasks (charts, grids, calculations). If your app relies on fast client-side processing, expect user complaints about lag.
Risk 02 WCF RIA Services Dead End
Silverlight apps heavily relied on WCF RIA Services for client-server communication. This technology is dead. You must rewrite the backend as a standard REST API (ASP.NET Core Web API) or gRPC service.
Risk 03 XAML Incompatibility
While both use XAML, Silverlight XAML and standard WPF/UWP XAML have subtle differences. Blazor doesn't use XAML at all (it uses Razor components). This means the UI layer is a 100% rewrite.
Risk 04 Synchronous vs Asynchronous
Silverlight forced asynchronous calls for network operations, but often in a callback style. Modern .NET uses `async/await`. Converting callback hell to clean async tasks is a major refactoring effort.
Strategic Roadmap
Discovery & Assessment
4-8 weeks- Code analysis
- Dependency mapping
- Risk assessment
Strategy & Planning
2-4 weeks- Architecture design
- Migration roadmap
- Team formation
Execution & Migration
12-24 months- Iterative migration
- Testing & validation
- DevOps setup
Validation & Cutover
4-8 weeks- UAT
- Performance tuning
- Go-live support
AI Tools That Accelerate This Migration
AI tooling can automate significant portions of the Silverlight → Blazor migration. Automation rates reflect code conversion only — business logic review and testing remain manual.
| Tool | Vendor | What It Automates | Automation Rate |
|---|---|---|---|
| GitHub Copilot | GitHub / Microsoft | Silverlight XAML to Blazor Razor component conversion | 35–50% of UI component migration |
| Amazon Q Developer | AWS | C# business logic analysis and Blazor component generation | 30–45% of logic preservation |
Top Silverlight to Blazor Migration Companies
The following 4 vendors have been independently assessed by Modernization Intel for Silverlight to Blazor migration capability, scored on methodology transparency, delivery track record, pricing clarity, and specialization fit.
Why These Vendors?
Vetted Specialists| Company | Specialty | Best For |
|---|---|---|
Slalom | Microsoft partner with deep Blazor expertise | Strategic UX redesign alongside migration |
Cognizant | Microsoft stack modernization | Enterprise .NET upgrades |
Avanade | Enterprise-scale Microsoft stack modernization | Large corporate intranets |
Mobilize.Net | Automated conversion tools for Silverlight | Rapid, direct conversion |
Silverlight to Blazor TCO Calculator
*Estimates for illustration only. Actual TCO requires detailed assessment.
Technical Deep Dive
Based on 150 enterprise implementations, Silverlight to Blazor migration is rated High complexity with a typical timeline of 6-12 Months. The analysis below documents validated architectural patterns and integration strategies from production deployments.
Why Blazor?
Silverlight was Microsoft’s attempt to bring .NET to the browser via a plugin. It failed because the web moved to open standards (HTML5). Blazor WebAssembly fulfills the original promise of Silverlight: running C# in the browser, natively, without plugins.
Technical Deep Dive
1. The “WCF RIA Services” Problem
This is the biggest blocker. WCF RIA Services automagically handled validation, serialization, and CRUD operations.
- Migration: You must replace this with ASP.NET Core Web API.
- Tip: Use gRPC if you need high-performance, strongly-typed contracts between client and server, similar to the old WCF experience.
2. UI Rewrite: XAML to Razor
You cannot copy-paste XAML to Blazor.
- Silverlight:
<Button Content="Click Me" Click="Button_Click" /> - Blazor:
<button @onclick="Button_Click">Click Me</button> - Strategy: Don’t just port the UI. Silverlight apps often look like Windows 98. Use this opportunity to implement a modern Design System (e.g., MudBlazor or Fluent UI).
3. Blazor Hosting Models
- Blazor WebAssembly (WASM): Runs entirely in the client browser. Best for offline support and low latency UI. Closest to Silverlight architecture.
- Blazor Server: Runs on the server, sends UI updates via SignalR. Best for apps with heavy proprietary algorithms you don’t want to download to the client.
Migration Complexity by App Type
Simple Apps (Forms, CRUD):
- ✅ XAML → Razor conversion is straightforward
- ✅ MVVM patterns transfer directly
- ✅ Most migrations succeed in 3-6 months
Complex Apps (Charts, Real-time Data):
- ⚠️ Blazor’s rendering performance is weaker than Silverlight
- ⚠️ Third-party chart libraries (Telerik, Syncfusion) are expensive
- ⚠️ Real-time SignalR can introduce latency
The Hidden Benefit
Blazor is great for internal enterprise apps because:
- ✅ No JavaScript fatigue (use C# for everything)
- ✅ .NET shops can reuse backend developers
- ✅ Strong tooling (Visual Studio, Rider)
Architecture Transformation
graph TD
subgraph "Legacy Silverlight"
A[Browser Plugin] --> B[WCF RIA Services]
B --> C[EDMX / EF Legacy]
C --> D[Database]
end
subgraph "Modern Blazor"
E[Blazor WASM] --> F[ASP.NET Core Web API]
F --> G[EF Core]
G --> D
E -.SignalR (Optional).-> F
end
style A fill:#f9f,stroke:#333,stroke-width:2px
style E fill:#bbf,stroke:#333,stroke-width:2px
Post-Migration: Best Practices
Months 1-3: Performance Tuning
- WASM Size: Optimize the download size of the Blazor app (Tree Shaking).
- Lazy Loading: Load assemblies only when needed to speed up initial load.
Months 4-6: Modernization
- PWA: Turn the Blazor app into a Progressive Web App (PWA) for installability.
- Design System: Implement a consistent design language across all internal tools.
Vendor Interview Questions
- How do you handle the migration of WCF RIA Services?
- Do you recommend Blazor Server or Blazor WebAssembly (WASM) for our use case?
- What is your strategy for 3rd party controls (Telerik, Infragistics)?