diff --git a/setup/installers.py b/setup/installers.py
index 064f243c89..0bbea71442 100644
--- a/setup/installers.py
+++ b/setup/installers.py
@@ -26,7 +26,7 @@ def get_exe():
     return 'python3' if sys.version_info.major == 2 else sys.executable
 
 
-def get_cmd(exe, bypy, which, bitness, sign_installers, notarize=True):
+def get_cmd(exe, bypy, which, bitness, sign_installers, notarize=True, compression_level='9'):
     cmd = [exe, bypy, which]
     if bitness and bitness == '32':
         cmd.append(bitness)
@@ -37,6 +37,7 @@ def get_cmd(exe, bypy, which, bitness, sign_installers, notarize=True):
         cmd.append('--sign-installers')
     if notarize:
         cmd.append('--notarize')
+    cmd.append('--compression-level=' + compression_level)
     return cmd
 
 
@@ -67,10 +68,10 @@ def build_only(which, bitness, spec, shutdown=False):
     return dist
 
 
-def build_single(which='windows', bitness='64', shutdown=True, sign_installers=True, notarize=True):
+def build_single(which='windows', bitness='64', shutdown=True, sign_installers=True, notarize=True, compression_level='9'):
     base, bypy = get_paths()
     exe = get_exe()
-    cmd = get_cmd(exe, bypy, which, bitness, sign_installers, notarize)
+    cmd = get_cmd(exe, bypy, which, bitness, sign_installers, notarize, compression_level=compression_level)
     ret = subprocess.Popen(cmd).wait()
     if ret != 0:
         raise SystemExit(ret)
@@ -123,9 +124,19 @@ class BuildInstaller(Command):
             action='store_true',
             help='Do not notarize the installers'
         )
+        parser.add_option(
+            '--compression-level',
+            default='9',
+            choices=list('123456789'),
+            help='Do not notarize the installers'
+        )
 
     def run(self, opts):
-        build_single(self.OS, self.BITNESS, not opts.dont_shutdown, not opts.dont_sign, not opts.dont_notarize)
+        build_single(
+            self.OS, self.BITNESS, not opts.dont_shutdown,
+            not opts.dont_sign, not opts.dont_notarize,
+            compression_level=opts.compression_level
+        )
 
 
 class BuildInstallers(BuildInstaller):