diff --git a/src/slipcover/__main__.py b/src/slipcover/__main__.py
index 9b0007d..91a11f8 100644
--- a/src/slipcover/__main__.py
+++ b/src/slipcover/__main__.py
@@ -272,6 +272,8 @@ def printit(coverage, outfile):
 
     atexit.register(sci_atexit)
 
+    return_code = 0
+
     if args.script:
         # python 'globals' for the script being executed
         script_globals: Dict[Any, Any] = dict()
@@ -297,20 +299,25 @@ def printit(coverage, outfile):
             code = sci.instrument(code)
 
         with sc.ImportManager(sci, file_matcher):
-            exec(code, script_globals)
-
+            try:
+                exec(code, script_globals)
+            except SystemExit as e:
+                return_code = e.code if e.code is not None else 0
     else:
         import runpy
         sys.argv = [*args.module, *args.script_or_module_args]
         with sc.ImportManager(sci, file_matcher):
-            runpy.run_module(*args.module, run_name='__main__', alter_sys=True)
+            try:
+                runpy.run_module(*args.module, run_name='__main__', alter_sys=True)
+            except SystemExit as e:
+                return_code = e.code if e.code is not None else 0
 
     if args.fail_under:
         cov = sci.get_coverage()
         if cov['summary']['percent_covered'] < args.fail_under:
             return 2
     
-    return 0
+    return return_code
 
 
 if __name__ == "__main__":
diff --git a/tests/branch.py b/tests/branch.py
index 05f0511..203245b 100644
--- a/tests/branch.py
+++ b/tests/branch.py
@@ -2,3 +2,5 @@ def foo(x):
     if x == 0:
         x += 1
 foo(0)
+
+raise SystemExit()
diff --git a/tests/test_coverage.py b/tests/test_coverage.py
index 49cee40..8668ac6 100644
--- a/tests/test_coverage.py
+++ b/tests/test_coverage.py
@@ -694,14 +694,20 @@ def test_summary_in_output_zero_lines(do_branch):
 
 
 @pytest.mark.parametrize("json_flag", ["", "--json"])
-def test_fail_under(json_flag):
+def test_fail_under(tmp_path, json_flag):
     p = subprocess.run(f"{sys.executable} -m slipcover {json_flag} --fail-under 100 tests/branch.py".split(), check=False)
     assert 0 == p.returncode
 
-    p = subprocess.run(f"{sys.executable} -m slipcover {json_flag} --branch --fail-under 83 tests/branch.py".split(), check=False)
+    p = subprocess.run(f"{sys.executable} -m slipcover {json_flag} --branch --fail-under 85 tests/branch.py".split(), check=False)
     assert 0 == p.returncode
 
-    p = subprocess.run(f"{sys.executable} -m slipcover {json_flag} --branch --fail-under 84 tests/branch.py".split(), check=False)
+    p = subprocess.run(f"{sys.executable} -m slipcover {json_flag} --branch --fail-under 86 tests/branch.py".split(), check=False)
+    assert 2 == p.returncode
+
+    p = subprocess.run(f"{sys.executable} -m slipcover --branch --fail-under 93 -m pytest tests/pyt.py".split(), check=False)
+    assert 0 == p.returncode
+
+    p = subprocess.run(f"{sys.executable} -m slipcover --branch --fail-under 94 -m pytest tests/pyt.py".split(), check=False)
     assert 2 == p.returncode