diff --git a/common/validators.cpp b/common/validators.cpp
index c8296c951e..eb0adad19d 100644
--- a/common/validators.cpp
+++ b/common/validators.cpp
@@ -167,7 +167,7 @@ void ENV_VAR_NAME_VALIDATOR::OnTextChanged( wxCommandEvent& event )
 
 NETNAME_VALIDATOR::NETNAME_VALIDATOR( wxString *aVal ) :
          wxTextValidator(),
-         m_allowSpaces( false )
+         m_allowSpaces( true )
 {
 }
 
diff --git a/qa/tests/common/CMakeLists.txt b/qa/tests/common/CMakeLists.txt
index 967f03fb6a..9f6dcb325a 100644
--- a/qa/tests/common/CMakeLists.txt
+++ b/qa/tests/common/CMakeLists.txt
@@ -92,6 +92,8 @@ set( QA_COMMON_SRCS
 
     view/test_zoom_controller.cpp
 
+    test_netname_validator.cpp
+
     # GAL tests
     test_gal_xor_mode.cpp
 
diff --git a/qa/tests/common/test_netname_validator.cpp b/qa/tests/common/test_netname_validator.cpp
new file mode 100644
index 0000000000..9c9bf8f192
--- /dev/null
+++ b/qa/tests/common/test_netname_validator.cpp
@@ -0,0 +1,88 @@
+/*
+ * This program source code file is part of KiCad, a free EDA CAD application.
+ *
+ * Copyright The KiCad Developers, see AUTHORS.txt for contributors.
+ *
+ * This program is free software: you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by the
+ * Free Software Foundation, either version 3 of the License, or (at your
+ * option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include <qa_utils/wx_utils/unit_test_utils.h>
+
+#include <validators.h>
+
+
+BOOST_AUTO_TEST_SUITE( NetnameValidator )
+
+
+struct ValidatorFixture
+{
+    ValidatorFixture() : m_validatorAllowSpaces( true ), m_validatorNoSpaces( false )
+    {
+    }
+
+    NETNAME_VALIDATOR m_validatorDefault;
+    NETNAME_VALIDATOR m_validatorAllowSpaces;
+    NETNAME_VALIDATOR m_validatorNoSpaces;
+};
+
+
+BOOST_FIXTURE_TEST_CASE( DefaultValidatorAllowsSpaces, ValidatorFixture )
+{
+    // Default validator should allow spaces (issue #9258)
+    BOOST_CHECK( m_validatorDefault.IsValid( wxS( "Net with spaces" ) ).IsEmpty() );
+    BOOST_CHECK( m_validatorDefault.IsValid( wxS( "Single_word" ) ).IsEmpty() );
+    BOOST_CHECK( m_validatorDefault.IsValid( wxS( "Net name with multiple spaces" ) ).IsEmpty() );
+}
+
+
+BOOST_FIXTURE_TEST_CASE( ValidatorAllowsSpacesWhenConfigured, ValidatorFixture )
+{
+    // Validator with allowSpaces=true should allow spaces
+    BOOST_CHECK( m_validatorAllowSpaces.IsValid( wxS( "Net with spaces" ) ).IsEmpty() );
+    BOOST_CHECK( m_validatorAllowSpaces.IsValid( wxS( "Single_word" ) ).IsEmpty() );
+}
+
+
+BOOST_FIXTURE_TEST_CASE( ValidatorRejectsSpacesWhenConfigured, ValidatorFixture )
+{
+    // Validator with allowSpaces=false should reject spaces
+    BOOST_CHECK( !m_validatorNoSpaces.IsValid( wxS( "Net with spaces" ) ).IsEmpty() );
+    BOOST_CHECK( m_validatorNoSpaces.IsValid( wxS( "Single_word" ) ).IsEmpty() );
+}
+
+
+BOOST_FIXTURE_TEST_CASE( ValidatorRejectsControlCharacters, ValidatorFixture )
+{
+    // All validators should reject CR and LF
+    BOOST_CHECK( !m_validatorDefault.IsValid( wxS( "Net\nname" ) ).IsEmpty() );
+    BOOST_CHECK( !m_validatorDefault.IsValid( wxS( "Net\rname" ) ).IsEmpty() );
+    BOOST_CHECK( !m_validatorAllowSpaces.IsValid( wxS( "Net\nname" ) ).IsEmpty() );
+    BOOST_CHECK( !m_validatorAllowSpaces.IsValid( wxS( "Net\rname" ) ).IsEmpty() );
+    BOOST_CHECK( !m_validatorNoSpaces.IsValid( wxS( "Net\nname" ) ).IsEmpty() );
+    BOOST_CHECK( !m_validatorNoSpaces.IsValid( wxS( "Net\rname" ) ).IsEmpty() );
+}
+
+
+BOOST_FIXTURE_TEST_CASE( ValidatorRejectsTabsWhenSpacesDisallowed, ValidatorFixture )
+{
+    // Validator with allowSpaces=false should reject tabs
+    BOOST_CHECK( !m_validatorNoSpaces.IsValid( wxS( "Net\twith\ttabs" ) ).IsEmpty() );
+
+    // Default and allowSpaces=true should accept tabs (they're treated like spaces)
+    BOOST_CHECK( m_validatorDefault.IsValid( wxS( "Net\twith\ttabs" ) ).IsEmpty() );
+    BOOST_CHECK( m_validatorAllowSpaces.IsValid( wxS( "Net\twith\ttabs" ) ).IsEmpty() );
+}
+
+
+BOOST_AUTO_TEST_SUITE_END()