diff --git a/crates/cli/src/subcommands/generate/csharp.rs b/crates/cli/src/subcommands/generate/csharp.rs
index 886550dd2a5..a393d05add2 100644
--- a/crates/cli/src/subcommands/generate/csharp.rs
+++ b/crates/cli/src/subcommands/generate/csharp.rs
@@ -814,6 +814,7 @@ pub fn autogen_csharp_globals(ctx: &GenCtx, items: &[GenItem], namespace: &str)
                         "\"{reducer_str_name}\" => new Reducer.{reducer_name}(BSATNHelpers.Decode<{reducer_name}>(encodedArgs)),"
                     );
                 }
+                writeln!(output, "\"<none>\" => new Reducer.StdbNone(default),");
                 writeln!(
                     output,
                     r#"var reducer => throw new ArgumentOutOfRangeException("Reducer", $"Unknown reducer {{reducer}}")"#
diff --git a/crates/cli/tests/snapshots/codegen__codegen_csharp.snap b/crates/cli/tests/snapshots/codegen__codegen_csharp.snap
index 3aa8a72e8ab..bcf33eb8f85 100644
--- a/crates/cli/tests/snapshots/codegen__codegen_csharp.snap
+++ b/crates/cli/tests/snapshots/codegen__codegen_csharp.snap
@@ -1178,6 +1178,7 @@ namespace SpacetimeDB
 				"repeating_test" => new Reducer.RepeatingTest(BSATNHelpers.Decode<RepeatingTest>(encodedArgs)),
 				"test" => new Reducer.Test(BSATNHelpers.Decode<Test>(encodedArgs)),
 				"test_btree_index_args" => new Reducer.TestBtreeIndexArgs(BSATNHelpers.Decode<TestBtreeIndexArgs>(encodedArgs)),
+				"<none>" => new Reducer.StdbNone(default),
 				var reducer => throw new ArgumentOutOfRangeException("Reducer", $"Unknown reducer {reducer}")
 			};
 		}