diff --git a/absl/numeric/int128.h b/absl/numeric/int128.h
index ae736b28463..fc03186a064 100644
--- a/absl/numeric/int128.h
+++ b/absl/numeric/int128.h
@@ -1190,15 +1190,15 @@ constexpr int64_t BitCastToSigned(uint64_t v) {
 
 }  // namespace int128_internal
 
+ABSL_NAMESPACE_END
+}  // namespace absl
+
 #if defined(ABSL_HAVE_INTRINSIC_INT128)
 #include "absl/numeric/int128_have_intrinsic.inc"  // IWYU pragma: export
 #else  // ABSL_HAVE_INTRINSIC_INT128
 #include "absl/numeric/int128_no_intrinsic.inc"  // IWYU pragma: export
 #endif  // ABSL_HAVE_INTRINSIC_INT128
 
-ABSL_NAMESPACE_END
-}  // namespace absl
-
 #undef ABSL_INTERNAL_WCHAR_T
 
 #endif  // ABSL_NUMERIC_INT128_H_
diff --git a/absl/numeric/int128_have_intrinsic.inc b/absl/numeric/int128_have_intrinsic.inc
index 216115a412b..69db5227a5c 100644
--- a/absl/numeric/int128_have_intrinsic.inc
+++ b/absl/numeric/int128_have_intrinsic.inc
@@ -17,6 +17,9 @@
 // representation when ABSL_HAVE_INTRINSIC_INT128 is defined. This file is
 // included by int128.h and relies on ABSL_INTERNAL_WCHAR_T being defined.
 
+namespace absl {
+ABSL_NAMESPACE_BEGIN
+
 namespace int128_internal {
 
 // Casts from unsigned to signed while preserving the underlying binary
@@ -307,3 +310,6 @@ constexpr int128 operator<<(int128 lhs, int amount) {
 constexpr int128 operator>>(int128 lhs, int amount) {
   return static_cast<__int128>(lhs) >> amount;
 }
+
+ABSL_NAMESPACE_END
+}  // namespace absl
diff --git a/absl/numeric/int128_no_intrinsic.inc b/absl/numeric/int128_no_intrinsic.inc
index a7cdceabfa6..dfaafbc3527 100644
--- a/absl/numeric/int128_no_intrinsic.inc
+++ b/absl/numeric/int128_no_intrinsic.inc
@@ -17,6 +17,9 @@
 // representation when ABSL_HAVE_INTRINSIC_INT128 is *not* defined. This file
 // is included by int128.h and relies on ABSL_INTERNAL_WCHAR_T being defined.
 
+namespace absl {
+ABSL_NAMESPACE_BEGIN
+
 constexpr uint64_t Int128Low64(int128 v) { return v.lo_; }
 
 constexpr int64_t Int128High64(int128 v) { return v.hi_; }
@@ -347,3 +350,6 @@ constexpr int128 operator>>(int128 lhs, int amount) {
         static_cast<uint64_t>(Int128High64(lhs) >> (amount - 64)));
   }
 }
+
+ABSL_NAMESPACE_END
+}  // namespace absl