diff --git a/include/fmt/os.h b/include/fmt/os.h
index 3127b9b0..70c465b5 100644
--- a/include/fmt/os.h
+++ b/include/fmt/os.h
@@ -200,10 +200,13 @@ FMT_API void report_windows_error(int error_code,
                                   string_view message) FMT_NOEXCEPT;
 #endif  // _WIN32
 
+// std::system is not available on iOS (#2248).
+#ifndef TARGET_OS_IPHONE
 template <typename S, typename... Args, typename Char = char_t<S>>
 void say(const S& format_str, Args&&... args) {
   std::system(format("say \"{}\"", format(format_str, args...)).c_str());
 }
+#endif
 
 // A buffered file.
 class buffered_file {