diff --git a/src/V3HierBlock.cpp b/src/V3HierBlock.cpp
index aa80e2ee3..22006fa23 100644
--- a/src/V3HierBlock.cpp
+++ b/src/V3HierBlock.cpp
@@ -306,10 +306,6 @@ public:
 
 //######################################################################
 
-bool V3HierBlockPlan::isHierBlock(const AstNodeModule* modp) const {
-    return m_blocks.find(modp) != m_blocks.end();
-}
-
 void V3HierBlockPlan::add(const AstNodeModule* modp, const std::vector<AstVar*>& gparams) {
     const iterator it = m_blocks.find(modp);
     if (it == m_blocks.end()) {
diff --git a/src/V3HierBlock.h b/src/V3HierBlock.h
index 7a01dd1a2..c247dce52 100644
--- a/src/V3HierBlock.h
+++ b/src/V3HierBlock.h
@@ -109,7 +109,6 @@ public:
     using HierVector = std::vector<const V3HierBlock*>;
     VL_DEBUG_FUNC;  // Declare debug()
 
-    bool isHierBlock(const AstNodeModule* modp) const;
     void add(const AstNodeModule* modp, const std::vector<AstVar*>& gparams);
     void registerUsage(const AstNodeModule* parentp, const AstNodeModule* childp);