diff --git a/src/ifcparse/file.h b/src/ifcparse/file.h
index 03d85c7243..b63f755d0f 100644
--- a/src/ifcparse/file.h
+++ b/src/ifcparse/file.h
@@ -112,6 +112,7 @@ private:
     std::vector<bool> types_to_bypass_materialized_;
 
     void initialize_header();
+    void materialize_bypass_types();
     spf_header& ensure_header();
 
   public:
diff --git a/src/ifcparse/parse.cpp b/src/ifcparse/parse.cpp
index 680a0e0045..18053da370 100644
--- a/src/ifcparse/parse.cpp
+++ b/src/ifcparse/parse.cpp
@@ -1938,6 +1938,27 @@ spf_header& ifcopenshell::instance_streamer<Reader>::ensure_header() {
     return *owned_header_;
 }
 
+template <typename Reader>
+void ifcopenshell::instance_streamer<Reader>::materialize_bypass_types() {
+    if (!schema_) {
+        return;
+    }
+
+    types_to_bypass_materialized_.assign(schema_->declarations().size(), false);
+    for (auto& bp : types_to_bypass_) {
+        std::function<void(const ifcopenshell::entity*)> mark;
+        mark = [&](const ifcopenshell::entity* e) {
+            types_to_bypass_materialized_[e->index_in_schema()] = true;
+            for (auto& subtype : e->subtypes()) {
+                mark(subtype);
+            }
+        };
+        if (auto* e = bp->as_entity()) {
+            mark(e);
+        }
+    }
+}
+
 template <typename Reader>
 void ifcopenshell::instance_streamer<Reader>::initialize_header() {
     storage_.file = owner_;
@@ -1959,21 +1980,7 @@ void ifcopenshell::instance_streamer<Reader>::initialize_header() {
 
     storage_.schema = schema_;
 
-    if (schema_) {
-        types_to_bypass_materialized_.resize(schema_->declarations().size(), false);
-        for (auto& bp : types_to_bypass_) {
-            std::function<void(const ifcopenshell::entity*)> mark;
-            mark = [&](const ifcopenshell::entity* e) {
-                types_to_bypass_materialized_[e->index_in_schema()] = true;
-                for (auto& subtype : e->subtypes()) {
-                    mark(subtype);
-                }
-            };
-            if (auto* e = bp->as_entity()) {
-                mark(e);
-            }
-        }
-    }
+    materialize_bypass_types();
 }
 
 template <typename Reader>
@@ -2132,6 +2139,7 @@ void ifcopenshell::instance_streamer<Reader>::bypass_types(const std::set<std::s
             continue;
         }
     }
+    materialize_bypass_types();
 }
 
 template <typename Reader>
diff --git a/src/ifcparse/tests/test_ifcopenshell_parse.cpp b/src/ifcparse/tests/test_ifcopenshell_parse.cpp
index c15f9dc537..d0f9c0c2ff 100644
--- a/src/ifcparse/tests/test_ifcopenshell_parse.cpp
+++ b/src/ifcparse/tests/test_ifcopenshell_parse.cpp
@@ -25,3 +25,13 @@ TEST_CASE("IfcPropertySetDefinitionSet references are resolved without replacing
     CHECK(definitions[0].id() == 136);
     CHECK(definitions[1].id() == 138);
 }
+
+TEST_CASE("Bypassed entity types include their subtypes", "[ifcparse]") {
+    const std::string fixture = std::string(IFCOPENSHELL_TEST_FIXTURES) + "/ColumnPSetsOfSets.ifc";
+    ifcopenshell::file file(ifcopenshell::uninitialized_tag{});
+    file.bypass_type("IfcRepresentationItem");
+
+    REQUIRE(file.initialize(fixture));
+    CHECK(file.instances_by_type("IfcRepresentationItem").empty());
+    CHECK(file.instances_by_type("IfcCartesianPoint").empty());
+}