diff --git a/tests/MaterialColorUtilities.Tests/CustomSemanticSwatchTests.cs b/tests/MaterialColorUtilities.Tests/CustomSemanticSwatchTests.cs
new file mode 100644
index 0000000000..8d2dfbbe0d
--- /dev/null
+++ b/tests/MaterialColorUtilities.Tests/CustomSemanticSwatchTests.cs
@@ -0,0 +1,170 @@
+using System.Windows.Media;
+
+namespace MaterialColorUtilities.Tests;
+
+public sealed class CustomSemanticSwatchTests
+{
+    [Test]
+    [Arguments(true)]
+    [Arguments(false)]
+    public async Task CustomSemanticSwatches_ExtractExpectedThemeColors(bool isDark)
+    {
+        var materialDynamicColors = new MaterialDynamicColors();
+
+        foreach (var semanticColor in GetSemanticColorExpectations())
+        {
+            foreach (var isDark in new[] { false, true })
+            {
+                var expected = isDark ? semanticColor.Dark : semanticColor.Light;
+                var scheme = CreateSchemeWithCustomErrorSwatch(semanticColor.Swatch, isDark);
+
+                await Assert.That(materialDynamicColors.ErrorPaletteKeyColor.GetColor(scheme))
+                    .IsEqualTo(expected.PaletteKey)
+                    .Because($"{semanticColor.Name} palette key did not match for {(isDark ? "dark" : "light")} mode.");
+
+                await Assert.That(materialDynamicColors.Error.GetColor(scheme))
+                    .IsEqualTo(expected.Role)
+                    .Because($"{semanticColor.Name} role color did not match for {(isDark ? "dark" : "light")} mode.");
+
+                await Assert.That(materialDynamicColors.OnError.GetColor(scheme))
+                    .IsEqualTo(expected.OnRole)
+                    .Because($"{semanticColor.Name} on-role color did not match for {(isDark ? "dark" : "light")} mode.");
+
+                await Assert.That(materialDynamicColors.ErrorContainer.GetColor(scheme))
+                    .IsEqualTo(expected.Container)
+                    .Because($"{semanticColor.Name} container color did not match for {(isDark ? "dark" : "light")} mode.");
+
+                await Assert.That(materialDynamicColors.OnErrorContainer.GetColor(scheme))
+                    .IsEqualTo(expected.OnContainer)
+                    .Because($"{semanticColor.Name} on-container color did not match for {(isDark ? "dark" : "light")} mode.");
+            }
+        }
+    }
+
+    private static DynamicScheme CreateSchemeWithCustomErrorSwatch(Color semanticSwatch, bool isDark)
+    {
+        var sourceColor = Color.FromArgb(255, 106, 156, 89);
+        var baseScheme = DynamicSchemeFactory.Create(
+            sourceColor,
+            Variant.TonalSpot,
+            isDark,
+            0.5,
+            Platform.Phone,
+            SpecVersion.Spec2025,
+            primary: null,
+            secondary: null,
+            tertiary: null,
+            neutral: null,
+            neutralVariant: null,
+            error: null);
+
+        return new DynamicScheme(
+            baseScheme.SourceColorHct,
+            baseScheme.Variant,
+            baseScheme.IsDark,
+            baseScheme.ContrastLevel,
+            baseScheme.PlatformType,
+            baseScheme.SpecVersion,
+            baseScheme.PrimaryPalette,
+            baseScheme.SecondaryPalette,
+            baseScheme.TertiaryPalette,
+            baseScheme.NeutralPalette,
+            baseScheme.NeutralVariantPalette,
+            TonalPalette.FromInt(ColorUtils.ArgbFromColor(semanticSwatch)));
+    }
+
+    private static SemanticColorExpectation[] GetSemanticColorExpectations()
+    {
+        return
+        [
+            new SemanticColorExpectation(
+                "WarningHigh",
+                Color.FromArgb(255, 212, 69, 41),
+                new ExtractedSemanticColors(
+                    PaletteKey: Color.FromArgb(255, 212, 69, 41),
+                    Role: Color.FromArgb(255, 111, 15, 0),
+                    OnRole: Colors.White,
+                    Container: Color.FromArgb(255, 198, 59, 32),
+                    OnContainer: Colors.White),
+                new ExtractedSemanticColors(
+                    PaletteKey: Color.FromArgb(255, 212, 69, 41),
+                    Role: Color.FromArgb(255, 255, 210, 201),
+                    OnRole: Color.FromArgb(255, 80, 8, 0),
+                    Container: Color.FromArgb(255, 247, 94, 63),
+                    OnContainer: Colors.Black)),
+            new SemanticColorExpectation(
+                "WarningLow",
+                Color.FromArgb(255, 252, 163, 41),
+                new ExtractedSemanticColors(
+                    PaletteKey: Color.FromArgb(255, 252, 163, 41),
+                    Role: Color.FromArgb(255, 80, 47, 0),
+                    OnRole: Colors.White,
+                    Container: Color.FromArgb(255, 156, 95, 0),
+                    OnContainer: Colors.White),
+                new ExtractedSemanticColors(
+                    PaletteKey: Color.FromArgb(255, 252, 163, 41),
+                    Role: Color.FromArgb(255, 255, 213, 169),
+                    OnRole: Color.FromArgb(255, 57, 32, 0),
+                    Container: Color.FromArgb(255, 205, 127, 0),
+                    OnContainer: Colors.Black)),
+            new SemanticColorExpectation(
+                "Information",
+                Color.FromArgb(255, 0, 46, 122),
+                new ExtractedSemanticColors(
+                    PaletteKey: Color.FromArgb(255, 0, 46, 122),
+                    Role: Color.FromArgb(255, 5, 49, 125),
+                    OnRole: Colors.White,
+                    Container: Color.FromArgb(255, 76, 106, 184),
+                    OnContainer: Colors.White),
+                new ExtractedSemanticColors(
+                    PaletteKey: Color.FromArgb(255, 0, 46, 122),
+                    Role: Color.FromArgb(255, 210, 219, 255),
+                    OnRole: Color.FromArgb(255, 0, 33, 93),
+                    Container: Color.FromArgb(255, 112, 142, 222),
+                    OnContainer: Colors.Black)),
+            new SemanticColorExpectation(
+                "Safe",
+                Color.FromArgb(255, 41, 138, 64),
+                new ExtractedSemanticColors(
+                    PaletteKey: Color.FromArgb(255, 41, 138, 64),
+                    Role: Color.FromArgb(255, 0, 64, 21),
+                    OnRole: Colors.White,
+                    Container: Color.FromArgb(255, 24, 126, 53),
+                    OnContainer: Colors.White),
+                new ExtractedSemanticColors(
+                    PaletteKey: Color.FromArgb(255, 41, 138, 64),
+                    Role: Color.FromArgb(255, 145, 242, 155),
+                    OnRole: Color.FromArgb(255, 0, 45, 12),
+                    Container: Color.FromArgb(255, 69, 163, 86),
+                    OnContainer: Colors.Black)),
+            new SemanticColorExpectation(
+                "Error",
+                Color.FromArgb(255, 163, 23, 26),
+                new ExtractedSemanticColors(
+                    PaletteKey: Color.FromArgb(255, 163, 23, 26),
+                    Role: Color.FromArgb(255, 115, 0, 9),
+                    OnRole: Colors.White,
+                    Container: Color.FromArgb(255, 201, 53, 49),
+                    OnContainer: Colors.White),
+                new ExtractedSemanticColors(
+                    PaletteKey: Color.FromArgb(255, 163, 23, 26),
+                    Role: Color.FromArgb(255, 255, 210, 205),
+                    OnRole: Color.FromArgb(255, 84, 0, 4),
+                    Container: Color.FromArgb(255, 251, 89, 80),
+                    OnContainer: Colors.Black))
+        ];
+    }
+
+    private sealed record SemanticColorExpectation(
+        string Name,
+        Color Swatch,
+        ExtractedSemanticColors Light,
+        ExtractedSemanticColors Dark);
+
+    private sealed record ExtractedSemanticColors(
+        Color PaletteKey,
+        Color Role,
+        Color OnRole,
+        Color Container,
+        Color OnContainer);
+}