diff --git a/src/IIIFPresentation/API.Tests/Converters/ManifestConverterTests.cs b/src/IIIFPresentation/API.Tests/Converters/ManifestConverterTests.cs
index c3285fd5..7f854433 100644
--- a/src/IIIFPresentation/API.Tests/Converters/ManifestConverterTests.cs
+++ b/src/IIIFPresentation/API.Tests/Converters/ManifestConverterTests.cs
@@ -107,7 +107,7 @@ public void SetGeneratedFields_SetsParentAndSlug_FromSingleHierarchyByDefault()
 
         // Assert
         result.Slug.Should().Be("hierarchy-slug");
-        result.Parent.Should().Be("hierarchy-parent");
+        result.Parent.Should().Be("/0/collections/hierarchy-parent", "Always use FlatId");
     }
     
     [Fact]
@@ -137,6 +137,6 @@ public void SetGeneratedFields_SetsParentAndSlug_FromHierarchyUsingFactory()
 
         // Assert
         result.Slug.Should().Be("other-slug");
-        result.Parent.Should().Be("other-parent");
+        result.Parent.Should().Be("/0/collections/other-parent", "Always use FlatId");
     } 
 }
\ No newline at end of file
diff --git a/src/IIIFPresentation/API.Tests/Helpers/CollectionHelperXTests.cs b/src/IIIFPresentation/API.Tests/Helpers/CollectionHelperXTests.cs
index 7e4784d4..884807f3 100644
--- a/src/IIIFPresentation/API.Tests/Helpers/CollectionHelperXTests.cs
+++ b/src/IIIFPresentation/API.Tests/Helpers/CollectionHelperXTests.cs
@@ -139,7 +139,8 @@ public void GenerateFlatId_Correct_Manifest()
     [Theory]
     [InlineData(ResourceType.StorageCollection)]
     [InlineData(ResourceType.IIIFCollection)]
-    public void GenerateFlatParentId_Correct_Collection(ResourceType resourceType)
+    [InlineData(ResourceType.IIIFManifest)]
+    public void GenerateFlatParentId_Correct(ResourceType resourceType)
     {
         // Arrange
         var hierarchy = new Hierarchy
@@ -156,24 +157,6 @@ public void GenerateFlatParentId_Correct_Collection(ResourceType resourceType)
         id.Should().Be("http://base/0/collections/parent");
     }
     
-    [Fact]
-    public void GenerateFlatParentId_Correct_Manifest()
-    {
-        // Arrange
-        var hierarchy = new Hierarchy
-        {
-            Slug = "slug",
-            Parent = "parent",
-            Type = ResourceType.IIIFManifest
-        };
-
-        // Act
-        var id = hierarchy.GenerateFlatParentId(urlRoots);
-
-        // Assert
-        id.Should().Be("http://base/0/manifests/parent");
-    }
-    
     [Fact]
     public void GenerateFlatCollectionViewId_CreatesViewId()
     {
diff --git a/src/IIIFPresentation/API.Tests/Integration/ModifyManifestTests.cs b/src/IIIFPresentation/API.Tests/Integration/ModifyManifestTests.cs
index b565108c..cf784c88 100644
--- a/src/IIIFPresentation/API.Tests/Integration/ModifyManifestTests.cs
+++ b/src/IIIFPresentation/API.Tests/Integration/ModifyManifestTests.cs
@@ -313,7 +313,7 @@ public async Task CreateManifest_CreatesManifest_ParentIsValidHierarchicalUrl()
         responseManifest.Modified.Should().BeCloseTo(DateTime.UtcNow, TimeSpan.FromSeconds(2));
         responseManifest.CreatedBy.Should().Be("Admin");
         responseManifest.Slug.Should().Be(slug);
-        responseManifest.Parent.Should().Be(RootCollection.Id);
+        responseManifest.Parent.Should().Be($"http://localhost/1/collections/{RootCollection.Id}");
     }
     
     [Fact]
@@ -343,7 +343,7 @@ public async Task CreateManifest_ReturnsManifest()
         responseManifest.Modified.Should().BeCloseTo(DateTime.UtcNow, TimeSpan.FromSeconds(2));
         responseManifest.CreatedBy.Should().Be("Admin");
         responseManifest.Slug.Should().Be(slug);
-        responseManifest.Parent.Should().Be(RootCollection.Id);
+        responseManifest.Parent.Should().Be($"http://localhost/1/collections/{RootCollection.Id}");
     }
     
     [Fact]
diff --git a/src/IIIFPresentation/API/Converters/ManifestConverter.cs b/src/IIIFPresentation/API/Converters/ManifestConverter.cs
index 0061f03c..08156c28 100644
--- a/src/IIIFPresentation/API/Converters/ManifestConverter.cs
+++ b/src/IIIFPresentation/API/Converters/ManifestConverter.cs
@@ -33,7 +33,7 @@ public static PresentationManifest SetGeneratedFields(this PresentationManifest
         iiifManifest.Modified = dbManifest.Modified.Floor(DateTimeX.Precision.Second);
         iiifManifest.CreatedBy = dbManifest.CreatedBy;
         iiifManifest.ModifiedBy = dbManifest.ModifiedBy;
-        iiifManifest.Parent = hierarchy.Parent;
+        iiifManifest.Parent = hierarchy.GenerateFlatParentId(urlRoots);
         iiifManifest.Slug = hierarchy.Slug;
         iiifManifest.EnsurePresentation3Context();
         iiifManifest.EnsureContext(PresentationJsonLdContext.Context);
diff --git a/src/IIIFPresentation/API/Helpers/CollectionHelperX.cs b/src/IIIFPresentation/API/Helpers/CollectionHelperX.cs
index 76ba8d6a..d5f710c8 100644
--- a/src/IIIFPresentation/API/Helpers/CollectionHelperX.cs
+++ b/src/IIIFPresentation/API/Helpers/CollectionHelperX.cs
@@ -35,10 +35,10 @@ public static string GenerateFlatId(this Hierarchy hierarchy, UrlRoots urlRoots)
         $"{urlRoots.BaseUrl}/{hierarchy.CustomerId}/{hierarchy.Type.GetSlug()}/{hierarchy.ResourceId}";
     
     /// <summary>
-    /// Get flat id for hierarchy parent 
+    /// Get flat id for parent of <see cref="Hierarchy"/> 
     /// </summary>
     public static string GenerateFlatParentId(this Hierarchy hierarchy, UrlRoots urlRoots) =>
-        $"{urlRoots.BaseUrl}/{hierarchy.CustomerId}/{hierarchy.Type.GetSlug()}/{hierarchy.Parent}";
+        $"{urlRoots.BaseUrl}/{hierarchy.CustomerId}/{CollectionsSlug}/{hierarchy.Parent}";
     
     public static string GenerateFlatCollectionViewId(this Collection collection, UrlRoots urlRoots, 
         int currentPage, int pageSize, string? orderQueryParam) =>