diff --git a/libraries/AP_Math/matrix3.h b/libraries/AP_Math/matrix3.h
index 3cba350cb7..a302a5752d 100644
--- a/libraries/AP_Math/matrix3.h
+++ b/libraries/AP_Math/matrix3.h
@@ -36,9 +36,7 @@
 // Matrix3ul	3x3 matrix of unsigned longs
 // Matrix3f		3x3 matrix of signed floats
 //
-
-#ifndef MATRIX3_H
-#define MATRIX3_H
+#pragma once
 
 #include "vector3.h"
 
@@ -242,5 +240,3 @@ typedef Matrix3<int32_t>                Matrix3l;
 typedef Matrix3<uint32_t>               Matrix3ul;
 typedef Matrix3<float>                  Matrix3f;
 typedef Matrix3<double>                 Matrix3d;
-
-#endif // MATRIX3_H
diff --git a/libraries/AP_Math/quaternion.h b/libraries/AP_Math/quaternion.h
index 0d62379397..32f3d2d93b 100644
--- a/libraries/AP_Math/quaternion.h
+++ b/libraries/AP_Math/quaternion.h
@@ -16,9 +16,7 @@
 
 // Copyright 2012 Andrew Tridgell, all rights reserved.
 // Refactored by Jonathan Challinger
-
-#ifndef QUATERNION_H
-#define QUATERNION_H
+#pragma once
 
 #include <math.h>
 #if MATH_CHECK_INDEXES
@@ -124,4 +122,3 @@ public:
     Quaternion &operator*=(const Quaternion &v);
     Quaternion operator/(const Quaternion &v) const;
 };
-#endif // QUATERNION_H
diff --git a/libraries/AP_Math/vector2.h b/libraries/AP_Math/vector2.h
index c599ed6496..e2bfcb1fdd 100644
--- a/libraries/AP_Math/vector2.h
+++ b/libraries/AP_Math/vector2.h
@@ -28,9 +28,7 @@
 * © 2003, This code is provided "as is" and you can use it freely as long as
 * credit is given to Bill Perone in the application it is used in
 ****************************************/
-
-#ifndef VECTOR2_H
-#define VECTOR2_H
+#pragma once
 
 #include <math.h>
 
@@ -161,5 +159,3 @@ typedef Vector2<uint16_t>       Vector2ui;
 typedef Vector2<int32_t>        Vector2l;
 typedef Vector2<uint32_t>       Vector2ul;
 typedef Vector2<float>          Vector2f;
-
-#endif // VECTOR2_H
diff --git a/libraries/AP_Math/vector3.h b/libraries/AP_Math/vector3.h
index 0f1617921a..01dcabbda8 100644
--- a/libraries/AP_Math/vector3.h
+++ b/libraries/AP_Math/vector3.h
@@ -46,9 +46,7 @@
 *           or if the matrix (A) * b = 0
 *
 ****************************************/
-
-#ifndef VECTOR3_H
-#define VECTOR3_H
+#pragma once
 
 #include <math.h>
 #include <float.h>
@@ -219,5 +217,3 @@ typedef Vector3<int32_t>                Vector3l;
 typedef Vector3<uint32_t>               Vector3ul;
 typedef Vector3<float>                  Vector3f;
 typedef Vector3<double>                 Vector3d;
-
-#endif // VECTOR3_H
diff --git a/libraries/AP_Math/vectorN.h b/libraries/AP_Math/vectorN.h
index cfd4bb4def..26b0433405 100644
--- a/libraries/AP_Math/vectorN.h
+++ b/libraries/AP_Math/vectorN.h
@@ -13,9 +13,7 @@
    You should have received a copy of the GNU General Public License
    along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
-
-#ifndef VECTORN_H
-#define VECTORN_H
+#pragma once
 
 #include <math.h>
 #include <string.h>
@@ -140,5 +138,3 @@ public:
 private:
     T _v[N];
 };
-
-#endif // VECTORN_H