diff --git a/include/sta/ArrayTable.hh b/include/sta/ArrayTable.hh
index 722fee9a..c5797115 100644
--- a/include/sta/ArrayTable.hh
+++ b/include/sta/ArrayTable.hh
@@ -6,8 +6,7 @@
 // disclosed in any form or fashion without the express
 // written consent of Parallax Software, Inc.
 
-#ifndef STA_ARRAY_TABLE_H
-#define STA_ARRAY_TABLE_H
+#pragma once
 
 #include <string.h> // memcpy
 
@@ -226,4 +225,3 @@ ArrayBlock<TYPE>::~ArrayBlock()
 }
 
 } // Namespace
-#endif
diff --git a/include/sta/VertexId.hh b/include/sta/VertexId.hh
index 9f1d3b48..a9c0939b 100644
--- a/include/sta/VertexId.hh
+++ b/include/sta/VertexId.hh
@@ -6,8 +6,7 @@
 // disclosed in any form or fashion without the express
 // written consent of Parallax Software, Inc.
 
-#ifndef STA_VERTEX_ID_H
-#define STA_VERTEX_ID_H
+#pragma once
 
 #include "ObjectId.hh"
 
diff --git a/search/WriteSpice.hh b/search/WriteSpice.hh
index ea104fbf..3a50022d 100644
--- a/search/WriteSpice.hh
+++ b/search/WriteSpice.hh
@@ -14,8 +14,7 @@
 // You should have received a copy of the GNU General Public License
 // along with this program.  If not, see <https://www.gnu.org/licenses/>.
 
-#ifndef STA_WRITE_SPICE_H
-#define STA_WRITE_SPICE_H
+#pragma once
 
 namespace sta {