diff --git a/src/HttpClientInterception/Bundles/BundleItemConverter.cs b/src/HttpClientInterception/Bundles/BundleItemConverter.cs
index 5bcb3fb2..c19d8eac 100644
--- a/src/HttpClientInterception/Bundles/BundleItemConverter.cs
+++ b/src/HttpClientInterception/Bundles/BundleItemConverter.cs
@@ -16,12 +16,10 @@ public static HttpRequestInterceptionBuilder FromItem(
         IEnumerable<KeyValuePair<string, string>> templateValues)
     {
         // Override the template values in the JSON with any user-specified values
-        if (item.TemplateValues?.Count > 0)
+        foreach (var pair in templateValues)
         {
-            foreach (var pair in templateValues)
-            {
-                item.TemplateValues[pair.Key] = pair.Value;
-            }
+            item.TemplateValues ??= new Dictionary<string, string>();
+            item.TemplateValues[pair.Key] = pair.Value;
         }
 
         ValidateItem(item, out Uri? uri, out Version? version);
diff --git a/tests/HttpClientInterception.Tests/Bundles/BundleExtensionsTests.cs b/tests/HttpClientInterception.Tests/Bundles/BundleExtensionsTests.cs
index 542bb139..fccd5dba 100644
--- a/tests/HttpClientInterception.Tests/Bundles/BundleExtensionsTests.cs
+++ b/tests/HttpClientInterception.Tests/Bundles/BundleExtensionsTests.cs
@@ -249,6 +249,32 @@ public static async Task Can_Intercept_Http_Requests_From_Bundle_File_With_Templ
             .ShouldBe(@"[{""id"":123456,""name"":""httpclient-interception"",""full_name"":""justeat/httpclient-interception"",""private"":false,""owner"":{""login"":""justeat"",""id"":1516790}}]");
     }
 
+    [Fact]
+    public static async Task Can_Intercept_Http_Requests_From_Bundle_File_With_Templated_Json_TemplateValues_Only_Defined_In_Code()
+    {
+        // Arrange
+        var options = new HttpClientInterceptorOptions().ThrowsOnMissingRegistration();
+
+        var templateValues = new Dictionary<string, string>()
+        {
+            ["AvatarUrl"] = "https://avatars.githubusercontent.com/u/1516790?v=4",
+            ["BlogUrl"] = "https://tech.justeattakeaway.com/",
+            ["CompanyName"] = "justeat",
+            ["RepoName"] = "httpclient-interception",
+        };
+
+        // Act
+        options.RegisterBundle(Path.Join("Bundles", "templated-bundle-json-no-parameters.json"), templateValues);
+
+        // Assert
+        string content = await HttpAssert.GetAsync(options, "https://api.github.com/orgs/justeat/repos");
+        content
+            .Replace(" ", string.Empty, StringComparison.Ordinal)
+            .Replace("\n", string.Empty, StringComparison.Ordinal)
+            .Replace("\r", string.Empty, StringComparison.Ordinal)
+            .ShouldBe(@"[{""id"":123456,""name"":""httpclient-interception"",""full_name"":""justeat/httpclient-interception"",""private"":false,""owner"":{""login"":""justeat"",""id"":1516790}}]");
+    }
+
     [Fact]
     public static void RegisterBundle_Validates_Parameters()
     {
diff --git a/tests/HttpClientInterception.Tests/Bundles/templated-bundle-json-no-parameters.json b/tests/HttpClientInterception.Tests/Bundles/templated-bundle-json-no-parameters.json
new file mode 100644
index 00000000..d08c8672
--- /dev/null
+++ b/tests/HttpClientInterception.Tests/Bundles/templated-bundle-json-no-parameters.json
@@ -0,0 +1,25 @@
+{
+  "$schema": "https://raw.githubusercontent.com/justeat/httpclient-interception/main/src/HttpClientInterception/Bundles/http-request-bundle-schema.json",
+  "id": "templated-bundle-json-no-parameters",
+  "comment": "An HTTP request bundle that uses templating for JSON where the parameters are only defined in code.",
+  "version": 1,
+  "items": [
+    {
+      "comment": "An HTTP request for a JSON response that uses templating.",
+      "uri": "https://api.github.com/orgs/${CompanyName}/repos",
+      "contentFormat": "json",
+      "contentJson": [
+        {
+          "id": 123456,
+          "name": "${RepoName}",
+          "full_name": "${CompanyName}/${RepoName}",
+          "private": false,
+          "owner": {
+            "login": "${CompanyName}",
+            "id": 1516790
+          }
+        }
+      ]
+    }
+  ]
+}