diff --git a/src/V3Options.cpp b/src/V3Options.cpp
index 1d4000b87..a39b2387b 100644
--- a/src/V3Options.cpp
+++ b/src/V3Options.cpp
@@ -804,7 +804,7 @@ void V3Options::parseOptsList(FileLine* fl, const string& optdir, int argc, char
             } else if (!strcmp(sw, "+librescan")) {  // NOP
             } else if (!strcmp(sw, "+notimingchecks")) {  // NOP
             } else {
-                fl->v3fatal("Invalid Option: " << argv[i]);
+                fl->v3fatal("Invalid option: " << argv[i]);
             }
             shift;
         }
@@ -1293,7 +1293,7 @@ void V3Options::parseOptsList(FileLine* fl, const string& optdir, int argc, char
                 shift;
                 addIncDirUser(parseFileArg(optdir, string(argv[i])));
             } else {
-                fl->v3fatal("Invalid Option: " << argv[i]);
+                fl->v3fatal("Invalid option: " << argv[i]);
             }
             shift;
         }  // - options
diff --git a/test_regress/t/t_flag_invalid2_bad.out b/test_regress/t/t_flag_invalid2_bad.out
new file mode 100644
index 000000000..e84f9a0d8
--- /dev/null
+++ b/test_regress/t/t_flag_invalid2_bad.out
@@ -0,0 +1 @@
+%Error: Invalid option: +invalid-plus
diff --git a/test_regress/t/t_flag_invalid2_bad.pl b/test_regress/t/t_flag_invalid2_bad.pl
new file mode 100755
index 000000000..42e60b698
--- /dev/null
+++ b/test_regress/t/t_flag_invalid2_bad.pl
@@ -0,0 +1,21 @@
+#!/usr/bin/perl
+if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); die; }
+# DESCRIPTION: Verilator: Verilog Test driver/expect definition
+#
+# Copyright 2003 by Wilson Snyder. This program is free software; you
+# can redistribute it and/or modify it under the terms of either the GNU
+# Lesser General Public License Version 3 or the Perl Artistic License
+# Version 2.0.
+# SPDX-License-Identifier: LGPL-3.0-only OR Artistic-2.0
+
+scenarios(vlt => 1);
+
+compile(
+    fails => 1,
+    verilator_flags2 => ['+invalid-plus'],
+    expect_filename => $Self->{golden_filename},
+    );
+
+ok(1);
+
+1;
diff --git a/test_regress/t/t_flag_invalid_bad.out b/test_regress/t/t_flag_invalid_bad.out
new file mode 100644
index 000000000..54d2f3d73
--- /dev/null
+++ b/test_regress/t/t_flag_invalid_bad.out
@@ -0,0 +1 @@
+%Error: Invalid option: --invalid-dash
diff --git a/test_regress/t/t_flag_invalid_bad.pl b/test_regress/t/t_flag_invalid_bad.pl
new file mode 100755
index 000000000..71aee1a28
--- /dev/null
+++ b/test_regress/t/t_flag_invalid_bad.pl
@@ -0,0 +1,21 @@
+#!/usr/bin/perl
+if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); die; }
+# DESCRIPTION: Verilator: Verilog Test driver/expect definition
+#
+# Copyright 2003 by Wilson Snyder. This program is free software; you
+# can redistribute it and/or modify it under the terms of either the GNU
+# Lesser General Public License Version 3 or the Perl Artistic License
+# Version 2.0.
+# SPDX-License-Identifier: LGPL-3.0-only OR Artistic-2.0
+
+scenarios(vlt => 1);
+
+compile(
+    fails => 1,
+    verilator_flags2 => ['--invalid-dash'],
+    expect_filename => $Self->{golden_filename},
+    );
+
+ok(1);
+
+1;