diff --git a/CHANGELOG.md b/CHANGELOG.md
index afa8dcea..b0d7b3a6 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -8,6 +8,7 @@
 * [NEW] Added .NET 9 to test matrix
 * [UPDATE] Migrate documentation to docfx platform. https://github.com/dotnet/docfx
 * [UPDATE][BREAKING] Nullability is enabled for public api for .NET Core TFMs
+* [UPDATE] Migrate to slnx format for solution file
 
 ### 5.3.0 (October 2024)
 
diff --git a/NSubstitute.sln b/NSubstitute.sln
deleted file mode 100644
index eae31164..00000000
--- a/NSubstitute.sln
+++ /dev/null
@@ -1,60 +0,0 @@
-Microsoft Visual Studio Solution File, Format Version 12.00
-# Visual Studio Version 17
-VisualStudioVersion = 17.8.34309.116
-MinimumVisualStudioVersion = 10.0.40219.1
-Project("{9A19103F-16F7-4668-BE54-9A1E7A4F7556}") = "NSubstitute", "src\NSubstitute\NSubstitute.csproj", "{F59BF5FC-52D8-492E-BDE8-244C183B4C92}"
-EndProject
-Project("{2150E333-8FDC-42A3-9474-1A3956D46DE8}") = "src", "src", "{CFB6BF4B-381D-4884-A8E8-D1FA71315BDE}"
-EndProject
-Project("{2150E333-8FDC-42A3-9474-1A3956D46DE8}") = "tests", "tests", "{0E2B9095-7548-462F-9BCC-CD6765B3ED60}"
-EndProject
-Project("{2150E333-8FDC-42A3-9474-1A3956D46DE8}") = "build", "build", "{A8AF7D01-6CE4-47B2-9E23-689A53991C3D}"
-	ProjectSection(SolutionItems) = preProject
-		build\build.fs = build\build.fs
-		build\ExtractDocs.fs = build\ExtractDocs.fs
-	EndProjectSection
-EndProject
-Project("{2150E333-8FDC-42A3-9474-1A3956D46DE8}") = "Solution Items", "Solution Items", "{CA2DD4AA-8DCD-42FB-8081-243281AD2956}"
-	ProjectSection(SolutionItems) = preProject
-		.editorconfig = .editorconfig
-		BreakingChanges.md = BreakingChanges.md
-		CHANGELOG.md = CHANGELOG.md
-		Directory.Build.props = Directory.Build.props
-		README.md = README.md
-	EndProjectSection
-EndProject
-Project("{9A19103F-16F7-4668-BE54-9A1E7A4F7556}") = "NSubstitute.Acceptance.Specs", "tests\NSubstitute.Acceptance.Specs\NSubstitute.Acceptance.Specs.csproj", "{8C2300AA-F94C-4005-A359-257C5EAD338E}"
-EndProject
-Project("{9A19103F-16F7-4668-BE54-9A1E7A4F7556}") = "NSubstitute.Benchmarks", "tests\NSubstitute.Benchmarks\NSubstitute.Benchmarks.csproj", "{D2D162D4-EF1D-4B40-8736-9228C2FEA16C}"
-EndProject
-Global
-	GlobalSection(SolutionConfigurationPlatforms) = preSolution
-		Debug|Any CPU = Debug|Any CPU
-		Release|Any CPU = Release|Any CPU
-	EndGlobalSection
-	GlobalSection(ProjectConfigurationPlatforms) = postSolution
-		{F59BF5FC-52D8-492E-BDE8-244C183B4C92}.Debug|Any CPU.ActiveCfg = Debug|Any CPU
-		{F59BF5FC-52D8-492E-BDE8-244C183B4C92}.Debug|Any CPU.Build.0 = Debug|Any CPU
-		{F59BF5FC-52D8-492E-BDE8-244C183B4C92}.Release|Any CPU.ActiveCfg = Release|Any CPU
-		{F59BF5FC-52D8-492E-BDE8-244C183B4C92}.Release|Any CPU.Build.0 = Release|Any CPU
-		{8C2300AA-F94C-4005-A359-257C5EAD338E}.Debug|Any CPU.ActiveCfg = Debug|Any CPU
-		{8C2300AA-F94C-4005-A359-257C5EAD338E}.Debug|Any CPU.Build.0 = Debug|Any CPU
-		{8C2300AA-F94C-4005-A359-257C5EAD338E}.Release|Any CPU.ActiveCfg = Release|Any CPU
-		{8C2300AA-F94C-4005-A359-257C5EAD338E}.Release|Any CPU.Build.0 = Release|Any CPU
-		{D2D162D4-EF1D-4B40-8736-9228C2FEA16C}.Debug|Any CPU.ActiveCfg = Debug|Any CPU
-		{D2D162D4-EF1D-4B40-8736-9228C2FEA16C}.Debug|Any CPU.Build.0 = Debug|Any CPU
-		{D2D162D4-EF1D-4B40-8736-9228C2FEA16C}.Release|Any CPU.ActiveCfg = Release|Any CPU
-		{D2D162D4-EF1D-4B40-8736-9228C2FEA16C}.Release|Any CPU.Build.0 = Release|Any CPU
-	EndGlobalSection
-	GlobalSection(SolutionProperties) = preSolution
-		HideSolutionNode = FALSE
-	EndGlobalSection
-	GlobalSection(NestedProjects) = preSolution
-		{F59BF5FC-52D8-492E-BDE8-244C183B4C92} = {CFB6BF4B-381D-4884-A8E8-D1FA71315BDE}
-		{8C2300AA-F94C-4005-A359-257C5EAD338E} = {0E2B9095-7548-462F-9BCC-CD6765B3ED60}
-		{D2D162D4-EF1D-4B40-8736-9228C2FEA16C} = {0E2B9095-7548-462F-9BCC-CD6765B3ED60}
-	EndGlobalSection
-	GlobalSection(ExtensibilityGlobals) = postSolution
-		SolutionGuid = {230E97F1-5246-4D49-8ED9-065F2B154E93}
-	EndGlobalSection
-EndGlobal
diff --git a/NSubstitute.slnx b/NSubstitute.slnx
new file mode 100644
index 00000000..f4a719ad
--- /dev/null
+++ b/NSubstitute.slnx
@@ -0,0 +1,20 @@
+<Solution>
+  <Folder Name="/build/">
+    <File Path="build/build.fs" />
+    <File Path="build/ExtractDocs.fs" />
+  </Folder>
+  <Folder Name="/Solution Items/">
+    <File Path=".editorconfig" />
+    <File Path="BreakingChanges.md" />
+    <File Path="CHANGELOG.md" />
+    <File Path="Directory.Build.props" />
+    <File Path="README.md" />
+  </Folder>
+  <Folder Name="/src/">
+    <Project Path="src/NSubstitute/NSubstitute.csproj" />
+  </Folder>
+  <Folder Name="/tests/">
+    <Project Path="tests/NSubstitute.Acceptance.Specs/NSubstitute.Acceptance.Specs.csproj" />
+    <Project Path="tests/NSubstitute.Benchmarks/NSubstitute.Benchmarks.csproj" />
+  </Folder>
+</Solution>
diff --git a/README.md b/README.md
index a3210e00..29cfad4f 100644
--- a/README.md
+++ b/README.md
@@ -1,6 +1,6 @@
 NSubstitute
 ========
-[![Build, Test, and Format verification](https://github.com/nsubstitute/NSubstitute/actions/workflows/test.yml/badge.svg)](https://github.com/nsubstitute/NSubstitute/actions/workflows/test.yml)
+[![Build, Test, and Format verification](https://github.com/nsubstitute/NSubstitute/actions/workflows/test.yml/badge.svg?branch=main)](https://github.com/nsubstitute/NSubstitute/actions/workflows/test.yml)
 [![Nuget](https://img.shields.io/nuget/v/NSubstitute.svg)](https://www.nuget.org/packages/NSubstitute)
 
 Visit the [NSubstitute website](https://nsubstitute.github.io) for more information.