diff --git a/CHANGELOG.md b/CHANGELOG.md
index 07a38e42..df282b71 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,3 +1,4 @@
+- Fixed stale model aliases from a "Claude Compatible API" profile still showing in the model selector after switching the profile to "Managed by Claude"
 - Fixed ClassNotFoundException on plugin installation/upgrade when the session tab had been previously saved under the old package name (https://github.com/nbplugins/NetbeansPluginClaudeCodeGui/issues/146)
 - Fixed a Warning dialog appearing on NetBeans exit when a diff tab had been opened during the session
 
diff --git a/pom.xml b/pom.xml
index ae7485d2..15626ccf 100644
--- a/pom.xml
+++ b/pom.xml
@@ -6,7 +6,7 @@
 
     <groupId>io.github.nbplugins</groupId>
     <artifactId>netbeans-plugin-claude-code-gui</artifactId>
-    <version>1.2.15-SNAPSHOT</version>
+    <version>1.2.16-SNAPSHOT</version>
     <packaging>nbm</packaging>
     <name>Netbeans Plugin Claude Code GUI</name>
     <description>NetBeans plugin that provides a GUI for Claude Code CLI — run claude code sessions directly inside the IDE.</description>
diff --git a/src/main/java/io/github/nbplugins/claudecodegui/settings/ClaudeProfile.java b/src/main/java/io/github/nbplugins/claudecodegui/settings/ClaudeProfile.java
index d4fb3743..acd51275 100644
--- a/src/main/java/io/github/nbplugins/claudecodegui/settings/ClaudeProfile.java
+++ b/src/main/java/io/github/nbplugins/claudecodegui/settings/ClaudeProfile.java
@@ -308,8 +308,11 @@ public Map<String, String> toEnvVars() {
             default -> { /* SYSTEM_MANAGED — inherit from parent process */ }
         }
 
-        // Model aliases (ANTHROPIC_DEFAULT_*_MODEL)
-        if (modelAliases != null) {
+        // Model aliases (ANTHROPIC_DEFAULT_*_MODEL) — only for connection types
+        // that use a custom endpoint; irrelevant (and potentially harmful) otherwise.
+        ConnectionType ct = computeConnectionType();
+        if ((ct == ConnectionType.OTHER_API || ct == ConnectionType.OPENAI_PROXY)
+                && modelAliases != null) {
             for (int i = 0; i < ALIAS_NAMES.length; i++) {
                 String modelId = modelAliases.get(ALIAS_NAMES[i]);
                 if (modelId != null && !modelId.isBlank()) {
diff --git a/src/main/java/io/github/nbplugins/claudecodegui/settings/ClaudeProfilesPanel.java b/src/main/java/io/github/nbplugins/claudecodegui/settings/ClaudeProfilesPanel.java
index 16c8b1b0..3c07ced0 100644
--- a/src/main/java/io/github/nbplugins/claudecodegui/settings/ClaudeProfilesPanel.java
+++ b/src/main/java/io/github/nbplugins/claudecodegui/settings/ClaudeProfilesPanel.java
@@ -615,6 +615,13 @@ private void flushFormToCurrentProfile() {
             p.setOpenaiProxy(false);
         }
 
+        // Clear model aliases/custom models when switching to a connection type that does not
+        // support them — prevents stale aliases from the old type appearing in the model combo box.
+        if (!rbOtherApi.isSelected() && !rbOpenAIProxy.isSelected()) {
+            p.setModelAliases(null);
+            p.setCustomModels(null);
+        }
+
         // Proxy
         if (rbProxyNone.isSelected()) {
             p.setProxyMode(ProxyMode.NO_PROXY);
diff --git a/src/test/java/io/github/nbplugins/claudecodegui/settings/ClaudeProfileTest.java b/src/test/java/io/github/nbplugins/claudecodegui/settings/ClaudeProfileTest.java
index 472bb73a..a545999e 100644
--- a/src/test/java/io/github/nbplugins/claudecodegui/settings/ClaudeProfileTest.java
+++ b/src/test/java/io/github/nbplugins/claudecodegui/settings/ClaudeProfileTest.java
@@ -387,4 +387,36 @@ void storageDir_jacksonRoundTrip() throws Exception {
         ClaudeProfile loaded = mapper.readValue(json, ClaudeProfile.class);
         assertEquals("/custom/path", loaded.getStorageDir());
     }
+
+    // -------------------------------------------------------------------------
+    // toEnvVars — model aliases (regression for stale-aliases-after-type-switch)
+    // -------------------------------------------------------------------------
+
+    @Test
+    void toEnvVars_doesNotInjectModelAliasesForManagedConnection() {
+        ClaudeProfile p = ClaudeProfile.createNamed("Test");
+        // no apiKey / token → CLAUDE_MANAGED
+        p.setModelAliases(Map.of("sonnet", "old-model-id"));
+        p.setCustomModels(List.of("old-custom-model"));
+
+        assertEquals(ConnectionType.CLAUDE_MANAGED, p.computeConnectionType());
+        Map<String, String> env = p.toEnvVars();
+
+        assertFalse(env.containsKey("ANTHROPIC_DEFAULT_SONNET_MODEL"),
+                "Model alias env vars must not be injected for CLAUDE_MANAGED connection");
+    }
+
+    @Test
+    void toEnvVars_injectsModelAliasesForOtherApiConnection() {
+        ClaudeProfile p = ClaudeProfile.createNamed("Test");
+        p.setApiKey("sk-test");
+        p.setBaseUrl("https://example.com");
+        p.setModelAliases(Map.of("sonnet", "my-sonnet-model"));
+
+        assertEquals(ConnectionType.OTHER_API, p.computeConnectionType());
+        Map<String, String> env = p.toEnvVars();
+
+        assertEquals("my-sonnet-model", env.get("ANTHROPIC_DEFAULT_SONNET_MODEL"),
+                "Model alias env vars must be injected for OTHER_API connection");
+    }
 }
diff --git a/src/test/java/io/github/nbplugins/claudecodegui/settings/ClaudeProfilesPanelFlushTest.java b/src/test/java/io/github/nbplugins/claudecodegui/settings/ClaudeProfilesPanelFlushTest.java
index 2f6b81d9..df6f7704 100644
--- a/src/test/java/io/github/nbplugins/claudecodegui/settings/ClaudeProfilesPanelFlushTest.java
+++ b/src/test/java/io/github/nbplugins/claudecodegui/settings/ClaudeProfilesPanelFlushTest.java
@@ -4,9 +4,11 @@
 import java.lang.reflect.Method;
 import java.util.ArrayList;
 import java.util.List;
+import java.util.Map;
 import javax.swing.JComboBox;
 import javax.swing.JPasswordField;
 import javax.swing.JRadioButton;
+import javax.swing.JTextField;
 import org.junit.jupiter.api.BeforeAll;
 import org.junit.jupiter.api.Test;
 import static org.junit.jupiter.api.Assertions.*;
@@ -64,6 +66,79 @@ void flushWritesToFormProfile_notComboSelection() throws Exception {
                 "Default profile must not receive Work's apiKey");
     }
 
+    /**
+     * Regression for stale model aliases after profile type switch:
+     * when a profile had model aliases set under "Claude Compatible API" and then
+     * the user switches to "Managed by Claude", flushFormToCurrentProfile must
+     * clear the stored modelAliases and customModels so they don't appear in the
+     * model combo box in the next session.
+     */
+    @Test
+    void flush_clearsModelAliasesWhenSwitchingToManaged() throws Exception {
+        ClaudeProfile work = ClaudeProfile.createNamed("Work");
+        work.setApiKey("sk-old");
+        work.setBaseUrl("https://old.example.com");
+        work.setModelAliases(Map.of("sonnet", "old-model"));
+        work.setCustomModels(List.of("old-custom-1", "old-custom-2"));
+
+        ClaudeProfilesPanel panel = new ClaudeProfilesPanel();
+        setField(panel, "profiles", new ArrayList<>(List.of(ClaudeProfile.createDefault(), work)));
+        rebuildCombo(panel);
+        invoke(panel, "loadProfileIntoForm", ClaudeProfile.class, work);
+
+        // Switch to "Managed by Claude" — clear API key and base URL
+        JPasswordField apiKeyField = getField(panel, "apiKeyField", JPasswordField.class);
+        apiKeyField.setText("");
+        JTextField baseUrlField = getField(panel, "baseUrlField", JTextField.class);
+        baseUrlField.setText("");
+        JRadioButton rbManaged = getField(panel, "rbManaged", JRadioButton.class);
+        rbManaged.setSelected(true);
+        // deselect others
+        for (String rb : new String[]{"rbSubscription", "rbClaudeApi", "rbOtherApi", "rbOpenAIProxy"}) {
+            getField(panel, rb, JRadioButton.class).setSelected(false);
+        }
+
+        invoke(panel, "flushFormToCurrentProfile");
+
+        assertTrue(work.getModelAliases().isEmpty(),
+                "modelAliases must be cleared when switching to Managed by Claude");
+        assertTrue(work.getCustomModels().isEmpty(),
+                "customModels must be cleared when switching to Managed by Claude");
+    }
+
+    @Test
+    void flush_keepsModelAliasesForOtherApiConnection() throws Exception {
+        ClaudeProfile work = ClaudeProfile.createNamed("Work");
+        work.setApiKey("sk-test");
+        work.setBaseUrl("https://example.com");
+        work.setModelAliases(Map.of("sonnet", "my-sonnet"));
+        work.setCustomModels(List.of("custom-1"));
+
+        ClaudeProfilesPanel panel = new ClaudeProfilesPanel();
+        setField(panel, "profiles", new ArrayList<>(List.of(ClaudeProfile.createDefault(), work)));
+        rebuildCombo(panel);
+        invoke(panel, "loadProfileIntoForm", ClaudeProfile.class, work);
+
+        // Keep "Other API" selected
+        JPasswordField apiKeyField = getField(panel, "apiKeyField", JPasswordField.class);
+        apiKeyField.setText("sk-test");
+        JTextField baseUrlField = getField(panel, "baseUrlField", JTextField.class);
+        baseUrlField.setText("https://example.com");
+        JRadioButton rbOtherApi = getField(panel, "rbOtherApi", JRadioButton.class);
+        rbOtherApi.setSelected(true);
+        for (String rb : new String[]{"rbManaged", "rbSubscription", "rbClaudeApi", "rbOpenAIProxy"}) {
+            getField(panel, rb, JRadioButton.class).setSelected(false);
+        }
+
+        invoke(panel, "flushFormToCurrentProfile");
+
+        // Model aliases must NOT be cleared when staying on Other API
+        assertFalse(work.getModelAliases().isEmpty(),
+                "modelAliases must be kept when connection type supports them");
+        assertFalse(work.getCustomModels().isEmpty(),
+                "customModels must be kept when connection type supports them");
+    }
+
     // -------------------------------------------------------------------------
     // Reflection helpers
     // -------------------------------------------------------------------------