diff --git a/tests/ScadaLink.CentralUI.Tests/Forms/OpcUaEndpointEditorTests.cs b/tests/ScadaLink.CentralUI.Tests/Forms/OpcUaEndpointEditorTests.cs
new file mode 100644
index 0000000..e6b1da0
--- /dev/null
+++ b/tests/ScadaLink.CentralUI.Tests/Forms/OpcUaEndpointEditorTests.cs
@@ -0,0 +1,85 @@
+using Bunit;
+using ScadaLink.Commons.Types.DataConnections;
+using ScadaLink.Commons.Types.Flattening;
+using ScadaLink.Commons.Validators;
+using OpcUaEndpointEditor = ScadaLink.CentralUI.Components.Forms.OpcUaEndpointEditor;
+
+namespace ScadaLink.CentralUI.Tests.Forms;
+
+public class OpcUaEndpointEditorTests : BunitContext
+{
+    [Fact]
+    public void Renders_All_Four_Section_Labels()
+    {
+        var config = new OpcUaEndpointConfig();
+        var cut = Render<OpcUaEndpointEditor>(p => p
+            .Add(c => c.Config, config)
+            .Add(c => c.Title, "Primary Endpoint"));
+
+        Assert.Contains("Primary Endpoint", cut.Markup);
+        Assert.Contains("Timing", cut.Markup);
+        Assert.Contains("Subscription", cut.Markup);
+        Assert.Contains("Heartbeat", cut.Markup);
+    }
+
+    [Fact]
+    public void Binding_MutatesPassedConfigInstance()
+    {
+        var config = new OpcUaEndpointConfig();
+        var cut = Render<OpcUaEndpointEditor>(p => p.Add(c => c.Config, config));
+
+        cut.Find("input[type='text']").Change("opc.tcp://new-host:4840");
+
+        Assert.Equal("opc.tcp://new-host:4840", config.EndpointUrl);
+    }
+
+    [Fact]
+    public void EnableHeartbeat_CreatesSubObject()
+    {
+        var config = new OpcUaEndpointConfig();
+        var cut = Render<OpcUaEndpointEditor>(p => p.Add(c => c.Config, config));
+
+        Assert.Null(config.Heartbeat);
+        cut.FindAll("button").First(b => b.TextContent.Contains("Enable Heartbeat")).Click();
+
+        Assert.NotNull(config.Heartbeat);
+    }
+
+    [Fact]
+    public void RemoveHeartbeat_NullsSubObject()
+    {
+        var config = new OpcUaEndpointConfig
+        {
+            Heartbeat = new OpcUaHeartbeatConfig { TagPath = "Hb", MaxSilenceSeconds = 30 }
+        };
+        var cut = Render<OpcUaEndpointEditor>(p => p.Add(c => c.Config, config));
+
+        cut.FindAll("button").First(b => b.TextContent.Contains("Remove Heartbeat")).Click();
+
+        Assert.Null(config.Heartbeat);
+    }
+
+    [Fact]
+    public void Errors_Parameter_RendersPerFieldRedText()
+    {
+        var config = new OpcUaEndpointConfig { EndpointUrl = "" };
+        var errors = OpcUaEndpointConfigValidator.Validate(config, "Primary.");
+        var cut = Render<OpcUaEndpointEditor>(p => p
+            .Add(c => c.Config, config)
+            .Add(c => c.Errors, errors));
+
+        Assert.Contains("Endpoint URL is required.", cut.Markup);
+        Assert.Contains("text-danger", cut.Markup);
+    }
+
+    [Fact]
+    public void IsLegacy_True_RendersWarningBanner()
+    {
+        var cut = Render<OpcUaEndpointEditor>(p => p
+            .Add(c => c.Config, new OpcUaEndpointConfig())
+            .Add(c => c.IsLegacy, true));
+
+        Assert.Contains("alert-warning", cut.Markup);
+        Assert.Contains("migrated from a legacy format", cut.Markup);
+    }
+}