diff --git a/.gitignore b/.gitignore
index df37204..5acd52d 100644
--- a/.gitignore
+++ b/.gitignore
@@ -1,4 +1,4 @@
-IntelliJ IDEA   
+IntelliJ IDEA
 *.swp
 *.*~
 project.lock.json
@@ -38,4 +38,6 @@ msbuild.wrn
 .vs/
 
 #Generator logs
-AutomaticInterfaceGenerator_log.txt
\ No newline at end of file
+AutomaticInterfaceGenerator_log.txt
+
+*.received.*
\ No newline at end of file
diff --git a/AutomaticInterface/AutomaticInterface/AutomaticInterface.csproj b/AutomaticInterface/AutomaticInterface/AutomaticInterface.csproj
index 5efb0d5..4de54bd 100644
--- a/AutomaticInterface/AutomaticInterface/AutomaticInterface.csproj
+++ b/AutomaticInterface/AutomaticInterface/AutomaticInterface.csproj
@@ -25,7 +25,7 @@
         <PackageLicenseExpression>MIT</PackageLicenseExpression>
         <EnableNETAnalyzers>True</EnableNETAnalyzers>
         <AnalysisLevel>latest-Recommended</AnalysisLevel>
-        <Version>5.1.2</Version>
+        <Version>5.1.3</Version>
         <PackageReadmeFile>README.md</PackageReadmeFile>
         <TreatWarningsAsErrors>true</TreatWarningsAsErrors>
         <NoWarn>1701;1702;NU5128</NoWarn>
diff --git a/AutomaticInterface/AutomaticInterface/RoslynExtensions.cs b/AutomaticInterface/AutomaticInterface/RoslynExtensions.cs
index b31827a..09a77ee 100644
--- a/AutomaticInterface/AutomaticInterface/RoslynExtensions.cs
+++ b/AutomaticInterface/AutomaticInterface/RoslynExtensions.cs
@@ -64,6 +64,12 @@ SymbolDisplayFormat typeDisplayFormat
                 isFirstConstraint = false;
             }
 
+            if (typeParameterSymbol.HasNotNullConstraint)
+            {
+                constraints += "notnull";
+                isFirstConstraint = false;
+            }
+
             foreach (var constraintType in typeParameterSymbol.ConstraintTypes)
             {
                 // if not first constraint prepend with comma
diff --git a/AutomaticInterface/Tests/Methods/Methods.WorksWithGenericTypeConstraintsForMethods.verified.txt b/AutomaticInterface/Tests/Methods/Methods.WorksWithGenericTypeConstraintsForMethods.verified.txt
new file mode 100644
index 0000000..f7bace4
--- /dev/null
+++ b/AutomaticInterface/Tests/Methods/Methods.WorksWithGenericTypeConstraintsForMethods.verified.txt
@@ -0,0 +1,18 @@
+//--------------------------------------------------------------------------------------------------
+// <auto-generated>
+//     This code was generated by a tool.
+//
+//     Changes to this file may cause incorrect behavior and will be lost if the code is regenerated.
+// </auto-generated>
+//--------------------------------------------------------------------------------------------------
+
+namespace AutomaticInterfaceExample
+{
+    [global::System.CodeDom.Compiler.GeneratedCode("AutomaticInterface", "")]
+    public partial interface IDemoClass
+    {
+        /// <inheritdoc cref="AutomaticInterfaceExample.DemoClass.AddFilter{T}(IQueryable{T})" />
+        IQueryable<T> AddFilter<T>(IQueryable<T> qry) where T : notnull;
+        
+    }
+}
diff --git a/AutomaticInterface/Tests/Methods/Methods.cs b/AutomaticInterface/Tests/Methods/Methods.cs
index 6542a4d..957f8e2 100644
--- a/AutomaticInterface/Tests/Methods/Methods.cs
+++ b/AutomaticInterface/Tests/Methods/Methods.cs
@@ -329,6 +329,27 @@ public string CMethod<T, T1, T2, T3, T4, T5>(string x, string y)
         await Verify(Infrastructure.GenerateCode(code));
     }
 
+    [Fact]
+    public async Task WorksWithGenericTypeConstraintsForMethods()
+    {
+        const string code = """
+
+            using AutomaticInterface;
+
+            namespace AutomaticInterfaceExample;
+
+            [GenerateAutomaticInterface]
+            public class DemoClass
+            {
+                public IQueryable<T> AddFilter<T>(IQueryable<T> qry) where T : notnull => qry;
+            }
+
+
+            """;
+
+        await Verify(Infrastructure.GenerateCode(code));
+    }
+
     [Fact]
     public async Task GeneratesOverloadedMethodInterface()
     {
diff --git a/AutomaticInterface/Tests/test.cs b/AutomaticInterface/Tests/test.cs
new file mode 100644
index 0000000..1357849
--- /dev/null
+++ b/AutomaticInterface/Tests/test.cs
@@ -0,0 +1,13 @@
+namespace Tests;
+
+public interface Itest
+{
+    IQueryable<T> AddFilter<T>(IQueryable<T> qry)
+        where T : notnull;
+}
+
+public class test : Itest
+{
+    public IQueryable<T> AddFilter<T>(IQueryable<T> qry)
+        where T : notnull => qry;
+}
diff --git a/README.md b/README.md
index 4bf2e76..2789cac 100644
--- a/README.md
+++ b/README.md
@@ -186,6 +186,10 @@ Note that we use [Verify](https://github.com/VerifyTests/Verify) for testing. It
 
 ## Changelog
 
+### 5.1.3.
+
+- Emit `notnull` type constraints on generic type parameters
+
 ### 5.1.2
 
 - Fixing enums in method signatures