diff --git a/base/include/android-base/chrono_utils.h b/base/include/android-base/chrono_utils.h
index b7647f2..11fcf71 100644
--- a/base/include/android-base/chrono_utils.h
+++ b/base/include/android-base/chrono_utils.h
@@ -14,8 +14,7 @@
  * limitations under the License.
  */
 
-#ifndef ANDROID_BASE_CHRONO_UTILS_H
-#define ANDROID_BASE_CHRONO_UTILS_H
+#pragma once
 
 #include <chrono>
 #include <sstream>
@@ -52,5 +51,3 @@
 
 }  // namespace base
 }  // namespace android
-
-#endif  // ANDROID_BASE_CHRONO_UTILS_H
diff --git a/base/include/android-base/endian.h b/base/include/android-base/endian.h
index 6eb677c..cbbd8c9 100644
--- a/base/include/android-base/endian.h
+++ b/base/include/android-base/endian.h
@@ -14,8 +14,7 @@
  * limitations under the License.
  */
 
-#ifndef ANDROID_BASE_ENDIAN_H
-#define ANDROID_BASE_ENDIAN_H
+#pragma once
 
 /* A cross-platform equivalent of bionic's <sys/endian.h>. */
 
@@ -86,5 +85,3 @@
 #define le64toh(x) (x)
 
 #endif
-
-#endif  // ANDROID_BASE_ENDIAN_H
diff --git a/base/include/android-base/errors.h b/base/include/android-base/errors.h
index 04c299c..06f29fc 100644
--- a/base/include/android-base/errors.h
+++ b/base/include/android-base/errors.h
@@ -27,8 +27,7 @@
 // special handling to get the error string. Refer to Microsoft documentation
 // to determine which error code to check for each function.
 
-#ifndef ANDROID_BASE_ERRORS_H
-#define ANDROID_BASE_ERRORS_H
+#pragma once
 
 #include <string>
 
@@ -42,5 +41,3 @@
 
 }  // namespace base
 }  // namespace android
-
-#endif  // ANDROID_BASE_ERRORS_H
diff --git a/base/include/android-base/file.h b/base/include/android-base/file.h
index 667d6fb..908690b 100644
--- a/base/include/android-base/file.h
+++ b/base/include/android-base/file.h
@@ -14,8 +14,7 @@
  * limitations under the License.
  */
 
-#ifndef ANDROID_BASE_FILE_H
-#define ANDROID_BASE_FILE_H
+#pragma once
 
 #include <sys/stat.h>
 #include <sys/types.h>
@@ -78,5 +77,3 @@
 
 }  // namespace base
 }  // namespace android
-
-#endif // ANDROID_BASE_FILE_H
diff --git a/base/include/android-base/logging.h b/base/include/android-base/logging.h
index 05a12e7..7f0801f 100644
--- a/base/include/android-base/logging.h
+++ b/base/include/android-base/logging.h
@@ -14,8 +14,7 @@
  * limitations under the License.
  */
 
-#ifndef ANDROID_BASE_LOGGING_H
-#define ANDROID_BASE_LOGGING_H
+#pragma once
 
 //
 // Google-style C++ logging.
@@ -506,5 +505,3 @@
 #undef OSTREAM_STRING_POINTER_USAGE_WARNING
 
 }  // namespace std
-
-#endif  // ANDROID_BASE_LOGGING_H
diff --git a/base/include/android-base/macros.h b/base/include/android-base/macros.h
index fd6efb2..0c8eac0 100644
--- a/base/include/android-base/macros.h
+++ b/base/include/android-base/macros.h
@@ -14,8 +14,7 @@
  * limitations under the License.
  */
 
-#ifndef ANDROID_BASE_MACROS_H
-#define ANDROID_BASE_MACROS_H
+#pragma once
 
 #include <stddef.h>  // for size_t
 #include <unistd.h>  // for TEMP_FAILURE_RETRY
@@ -197,5 +196,3 @@
 #elif defined(__mips__) && defined(__LP64__)
 #define ABI_STRING "mips64"
 #endif
-
-#endif  // ANDROID_BASE_MACROS_H
diff --git a/base/include/android-base/memory.h b/base/include/android-base/memory.h
index 9971226..0277a03 100644
--- a/base/include/android-base/memory.h
+++ b/base/include/android-base/memory.h
@@ -14,8 +14,7 @@
  * limitations under the License.
  */
 
-#ifndef ANDROID_BASE_MEMORY_H
-#define ANDROID_BASE_MEMORY_H
+#pragma once
 
 namespace android {
 namespace base {
@@ -37,5 +36,3 @@
 
 } // namespace base
 } // namespace android
-
-#endif  // ANDROID_BASE_MEMORY_H
diff --git a/base/include/android-base/parsedouble.h b/base/include/android-base/parsedouble.h
index daa6902..c273c61 100644
--- a/base/include/android-base/parsedouble.h
+++ b/base/include/android-base/parsedouble.h
@@ -14,8 +14,7 @@
  * limitations under the License.
  */
 
-#ifndef ANDROID_BASE_PARSEDOUBLE_H
-#define ANDROID_BASE_PARSEDOUBLE_H
+#pragma once
 
 #include <errno.h>
 #include <stdlib.h>
@@ -46,5 +45,3 @@
 
 }  // namespace base
 }  // namespace android
-
-#endif  // ANDROID_BASE_PARSEDOUBLE_H
diff --git a/base/include/android-base/parseint.h b/base/include/android-base/parseint.h
index 1b7cc5f..b0fc7c3 100644
--- a/base/include/android-base/parseint.h
+++ b/base/include/android-base/parseint.h
@@ -14,8 +14,7 @@
  * limitations under the License.
  */
 
-#ifndef ANDROID_BASE_PARSEINT_H
-#define ANDROID_BASE_PARSEINT_H
+#pragma once
 
 #include <errno.h>
 #include <stdlib.h>
@@ -104,5 +103,3 @@
 
 }  // namespace base
 }  // namespace android
-
-#endif  // ANDROID_BASE_PARSEINT_H
diff --git a/base/include/android-base/parsenetaddress.h b/base/include/android-base/parsenetaddress.h
index b4ac025..47f8b5f 100644
--- a/base/include/android-base/parsenetaddress.h
+++ b/base/include/android-base/parsenetaddress.h
@@ -14,8 +14,7 @@
  * limitations under the License.
  */
 
-#ifndef ANDROID_BASE_PARSENETADDRESS_H
-#define ANDROID_BASE_PARSENETADDRESS_H
+#pragma once
 
 #include <string>
 
@@ -34,5 +33,3 @@
 
 }  // namespace base
 }  // namespace android
-
-#endif  // ANDROID_BASE_PARSENETADDRESS_H
diff --git a/base/include/android-base/properties.h b/base/include/android-base/properties.h
index 3a05143..31e5273 100644
--- a/base/include/android-base/properties.h
+++ b/base/include/android-base/properties.h
@@ -14,8 +14,7 @@
  * limitations under the License.
  */
 
-#ifndef ANDROID_BASE_PROPERTIES_H
-#define ANDROID_BASE_PROPERTIES_H
+#pragma once
 
 #include <sys/cdefs.h>
 
@@ -73,5 +72,3 @@
 
 } // namespace base
 } // namespace android
-
-#endif  // ANDROID_BASE_PROPERTIES_H
diff --git a/base/include/android-base/scopeguard.h b/base/include/android-base/scopeguard.h
index c314e02..e6a9d10 100644
--- a/base/include/android-base/scopeguard.h
+++ b/base/include/android-base/scopeguard.h
@@ -14,8 +14,7 @@
  * limitations under the License.
  */
 
-#ifndef ANDROID_BASE_SCOPEGUARD_H
-#define ANDROID_BASE_SCOPEGUARD_H
+#pragma once
 
 #include <utility>  // for std::move, std::forward
 
@@ -66,5 +65,3 @@
 
 }  // namespace base
 }  // namespace android
-
-#endif  // ANDROID_BASE_SCOPEGUARD_H
diff --git a/base/include/android-base/stringprintf.h b/base/include/android-base/stringprintf.h
index c13d25d..93c56af 100644
--- a/base/include/android-base/stringprintf.h
+++ b/base/include/android-base/stringprintf.h
@@ -14,8 +14,7 @@
  * limitations under the License.
  */
 
-#ifndef ANDROID_BASE_STRINGPRINTF_H
-#define ANDROID_BASE_STRINGPRINTF_H
+#pragma once
 
 #include <stdarg.h>
 #include <string>
@@ -39,5 +38,3 @@
 
 }  // namespace base
 }  // namespace android
-
-#endif  // ANDROID_BASE_STRINGPRINTF_H
diff --git a/base/include/android-base/strings.h b/base/include/android-base/strings.h
index 4d9fa34..9c35560 100644
--- a/base/include/android-base/strings.h
+++ b/base/include/android-base/strings.h
@@ -14,8 +14,7 @@
  * limitations under the License.
  */
 
-#ifndef ANDROID_BASE_STRINGS_H
-#define ANDROID_BASE_STRINGS_H
+#pragma once
 
 #include <sstream>
 #include <string>
@@ -75,5 +74,3 @@
 
 }  // namespace base
 }  // namespace android
-
-#endif  // ANDROID_BASE_STRINGS_H
diff --git a/base/include/android-base/test_utils.h b/base/include/android-base/test_utils.h
index b29676f..9e2ea97 100644
--- a/base/include/android-base/test_utils.h
+++ b/base/include/android-base/test_utils.h
@@ -14,8 +14,7 @@
  * limitations under the License.
  */
 
-#ifndef ANDROID_BASE_TEST_UTILS_H
-#define ANDROID_BASE_TEST_UTILS_H
+#pragma once
 
 #include <regex>
 #include <string>
@@ -114,5 +113,3 @@
       ADD_FAILURE() << "regex mismatch: expected to not find " << (pattern) << " in:\n" << (str); \
     }                                                                                             \
   } while (0)
-
-#endif  // ANDROID_BASE_TEST_UTILS_H
diff --git a/base/include/android-base/thread_annotations.h b/base/include/android-base/thread_annotations.h
index 1307f0e..d56e935 100644
--- a/base/include/android-base/thread_annotations.h
+++ b/base/include/android-base/thread_annotations.h
@@ -14,8 +14,7 @@
  * limitations under the License.
  */
 
-#ifndef ANDROID_BASE_THREAD_ANNOTATIONS_H
-#define ANDROID_BASE_THREAD_ANNOTATIONS_H
+#pragma once
 
 #if defined(__SUPPORT_TS_ANNOTATION__) || defined(__clang__)
 #define THREAD_ANNOTATION_ATTRIBUTE__(x)   __attribute__((x))
@@ -109,5 +108,3 @@
 
 #define NO_THREAD_SAFETY_ANALYSIS \
       THREAD_ANNOTATION_ATTRIBUTE__(no_thread_safety_analysis)
-
-#endif  // ANDROID_BASE_THREAD_ANNOTATIONS_H
diff --git a/base/include/android-base/threads.h b/base/include/android-base/threads.h
index 85e65ba..f4ba809 100644
--- a/base/include/android-base/threads.h
+++ b/base/include/android-base/threads.h
@@ -14,8 +14,7 @@
  * limitations under the License.
  */
 
-#ifndef ANDROID_BASE_THREADS_H
-#define ANDROID_BASE_THREADS_H
+#pragma once
 
 #include <stdint.h>
 
@@ -24,5 +23,3 @@
 uint64_t GetThreadId();
 }
 }  // namespace android
-
-#endif
diff --git a/base/include/android-base/unique_fd.h b/base/include/android-base/unique_fd.h
index 5d89271..d334e30 100644
--- a/base/include/android-base/unique_fd.h
+++ b/base/include/android-base/unique_fd.h
@@ -14,8 +14,7 @@
  * limitations under the License.
  */
 
-#ifndef ANDROID_BASE_UNIQUE_FD_H
-#define ANDROID_BASE_UNIQUE_FD_H
+#pragma once
 
 #include <fcntl.h>
 
@@ -150,5 +149,3 @@
 #endif
     "close called on unique_fd"
   )));
-
-#endif  // ANDROID_BASE_UNIQUE_FD_H
diff --git a/base/include/android-base/utf8.h b/base/include/android-base/utf8.h
index c9cc1ab..4b91623 100755
--- a/base/include/android-base/utf8.h
+++ b/base/include/android-base/utf8.h
@@ -14,8 +14,7 @@
  * limitations under the License.
  */
 
-#ifndef ANDROID_BASE_UTF8_H
-#define ANDROID_BASE_UTF8_H
+#pragma once
 
 #ifdef _WIN32
 #include <string>
@@ -102,5 +101,3 @@
 }  // namespace utf8
 }  // namespace base
 }  // namespace android
-
-#endif  // ANDROID_BASE_UTF8_H