diff --git a/var/spack/repos/builtin/packages/mgard/package.py b/var/spack/repos/builtin/packages/mgard/package.py
index 948ccabf0b2..c3abc1a5cfd 100644
--- a/var/spack/repos/builtin/packages/mgard/package.py
+++ b/var/spack/repos/builtin/packages/mgard/package.py
@@ -73,6 +73,8 @@ def flag_handler(self, name, flags):
         if name == "cxxflags":
             if self.spec.satisfies("@2020-10-01 %oneapi@2023:"):
                 flags.append("-Wno-error=c++11-narrowing")
+            if self.spec.satisfies("@2020-10-01 %apple-clang@15:"):
+                flags.append("-Wno-error=c++11-narrowing")
         return (flags, None, None)
 
     def cmake_args(self):