diff --git a/include/boost/unordered/detail/foa.hpp b/include/boost/unordered/detail/foa.hpp
index 61fbf732..0f9f1b79 100644
--- a/include/boost/unordered/detail/foa.hpp
+++ b/include/boost/unordered/detail/foa.hpp
@@ -39,12 +39,24 @@
 #include <type_traits>
 #include <utility>
 
-#if defined(__SSE2__)||\
+#if !defined(BOOST_UNORDERED_DISABLE_SSE2)
+#if defined(BOOST_UNORDERED_ENABLE_SSE2)|| \
+    defined(__SSE2__)|| \
     defined(_M_X64)||(defined(_M_IX86_FP)&&_M_IX86_FP>=2)
 #define BOOST_UNORDERED_SSE2
-#include <emmintrin.h>
-#elif defined(__ARM_NEON)&&!defined(__ARM_BIG_ENDIAN)
+#endif
+#endif
+
+#if !defined(BOOST_UNORDERED_DISABLE_NEON)
+#if defined(BOOST_UNORDERED_ENABLE_NEON)||\
+    (defined(__ARM_NEON)&&!defined(__ARM_BIG_ENDIAN))
 #define BOOST_UNORDERED_LITTLE_ENDIAN_NEON
+#endif
+#endif
+
+#if defined(BOOST_UNORDERED_SSE2)
+#include <emmintrin.h>
+#elif defined(BOOST_UNORDERED_LITTLE_ENDIAN_NEON)
 #include <arm_neon.h>
 #endif
 
@@ -2198,13 +2210,7 @@ private:
 } /* namespace unordered */
 } /* namespace boost */
 
+#undef BOOST_UNORDERED_STATIC_ASSERT_HASH_PRED
 #undef BOOST_UNORDERED_ASSUME
 #undef BOOST_UNORDERED_HAS_BUILTIN
-#undef BOOST_UNORDERED_STATIC_ASSERT_HASH_PRED
-#ifdef BOOST_UNORDERED_LITTLE_ENDIAN_NEON
-#undef BOOST_UNORDERED_LITTLE_ENDIAN_NEON
-#endif
-#ifdef BOOST_UNORDERED_SSE2
-#undef BOOST_UNORDERED_SSE2
-#endif
 #endif