diff --git a/CHANGELOG.md b/CHANGELOG.md
index 3515a80c..35569262 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,3 +1,4 @@
+- Fixed Default profile settings (API key, connection type, proxy, etc.) not being saved when edited in Tools → Options → Claude Code → Profiles
 - Fixed MCP config not working on Windows due to quote stripping in CreateProcess (https://github.com/nbclaudecodegui/NetbeansClaudeCodeGui/issues/13)
 - Improved error panel on process start failure: shows Working Directory and CLAUDE_CONFIG_DIR fields (before Command and Error) for easier diagnosis; all fields have a right-click Copy menu; fixed "Restart Advanced…" not dismissing the error panel
 - Added Advanced tab in Tools → Options → Claude Code with Debug mode, Hang timeout, and a new "Enable MCP integration" toggle (disabling it skips the --mcp-config flag while hooks remain active)
diff --git a/pom.xml b/pom.xml
index 7a1e19f9..76c0ac7c 100644
--- a/pom.xml
+++ b/pom.xml
@@ -6,7 +6,7 @@
 
     <groupId>io.github.nbclaudecodegui</groupId>
     <artifactId>netbeans-claude-code-gui</artifactId>
-    <version>0.21.39-SNAPSHOT</version>
+    <version>0.21.40-SNAPSHOT</version>
     <packaging>nbm</packaging>
     <name>Netbeans 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/nbclaudecodegui/settings/ClaudeProfileStore.java b/src/main/java/io/github/nbclaudecodegui/settings/ClaudeProfileStore.java
index 6b559969..ccfa8a60 100644
--- a/src/main/java/io/github/nbclaudecodegui/settings/ClaudeProfileStore.java
+++ b/src/main/java/io/github/nbclaudecodegui/settings/ClaudeProfileStore.java
@@ -34,6 +34,9 @@ public final class ClaudeProfileStore {
     /** NbPreferences key under which the JSON array is stored. */
     public static final String KEY_PROFILES = "profiles";
 
+    /** NbPreferences key under which the full Default profile JSON is stored. */
+    private static final String KEY_DEFAULT_PROFILE = "defaultProfile";
+
     private static final ObjectMapper MAPPER = new ObjectMapper()
             .disable(DeserializationFeature.FAIL_ON_UNKNOWN_PROPERTIES);
     private static final TypeReference<List<ClaudeProfile>> LIST_TYPE =
@@ -56,7 +59,32 @@ private ClaudeProfileStore() {}
     public static List<ClaudeProfile> getProfiles() {
         List<ClaudeProfile> result = new ArrayList<>();
         ClaudeProfile def = ClaudeProfile.createDefault();
-        def.setExtraCliArgs(ClaudeCodePreferences.getDefaultExtraCliArgs());
+
+        String defaultJson = NbPreferences.forModule(ClaudeProfileStore.class)
+                .get(KEY_DEFAULT_PROFILE, null);
+        if (defaultJson != null) {
+            try {
+                ClaudeProfile stored = MAPPER.readValue(defaultJson, ClaudeProfile.class);
+                def.setToken(stored.getToken());
+                def.setApiKey(stored.getApiKey());
+                def.setBaseUrl(stored.getBaseUrl());
+                def.setProxyMode(stored.getProxyMode());
+                def.setHttpProxy(stored.getHttpProxy());
+                def.setHttpsProxy(stored.getHttpsProxy());
+                def.setNoProxy(stored.getNoProxy());
+                def.setExtraEnvVars(stored.getExtraEnvVars());
+                def.setExtraCliArgs(stored.getExtraCliArgs());
+                def.setModelAliases(stored.getModelAliases());
+                def.setCustomModels(stored.getCustomModels());
+                def.setStorageDir(stored.getStorageDir());
+            } catch (Exception e) {
+                LOG.warning("Could not parse stored Default profile JSON, using defaults. Cause: " + e);
+                def.setExtraCliArgs(ClaudeCodePreferences.getDefaultExtraCliArgs());
+            }
+        } else {
+            def.setExtraCliArgs(ClaudeCodePreferences.getDefaultExtraCliArgs());
+        }
+
         result.add(def);
 
         String json = NbPreferences.forModule(ClaudeProfileStore.class)
@@ -108,7 +136,14 @@ public static void saveProfiles(List<ClaudeProfile> profiles) {
         if (profiles != null) {
             for (ClaudeProfile p : profiles) {
                 if (p.isDefault()) {
-                    ClaudeCodePreferences.setDefaultExtraCliArgs(p.getExtraCliArgs());
+                    ClaudeCodePreferences.setDefaultExtraCliArgs(p.getExtraCliArgs()); // back-compat
+                    try {
+                        String defaultJson = MAPPER.writeValueAsString(p);
+                        NbPreferences.forModule(ClaudeProfileStore.class)
+                                .put(KEY_DEFAULT_PROFILE, defaultJson);
+                    } catch (Exception e) {
+                        LOG.severe("Could not serialise Default profile: " + e.getMessage());
+                    }
                 } else {
                     toSave.add(p);
                 }
diff --git a/src/test/java/io/github/nbclaudecodegui/settings/ClaudeProfileStoreTest.java b/src/test/java/io/github/nbclaudecodegui/settings/ClaudeProfileStoreTest.java
index 35d1bba1..063060b5 100644
--- a/src/test/java/io/github/nbclaudecodegui/settings/ClaudeProfileStoreTest.java
+++ b/src/test/java/io/github/nbclaudecodegui/settings/ClaudeProfileStoreTest.java
@@ -203,6 +203,83 @@ void extraCliArgs_jacksonRoundTrip() throws Exception {
         assertEquals("--verbose --model foo", loaded.get(0).getExtraCliArgs());
     }
 
+    // -------------------------------------------------------------------------
+    // Default profile full round-trip (bug: all fields except extraCliArgs were lost)
+    // -------------------------------------------------------------------------
+
+    @Test
+    void defaultProfile_allFields_roundTrip() {
+        try {
+            ClaudeProfile def = ClaudeProfile.createDefault();
+            def.setApiKey("sk-api-key-123");
+            def.setToken("oauth-token-xyz");
+            def.setBaseUrl("https://custom.api.example.com");
+            def.setProxyMode(ClaudeProfile.ProxyMode.CUSTOM);
+            def.setHttpProxy("http://proxy.example.com:8080");
+            def.setHttpsProxy("https://proxy.example.com:8443");
+            def.setNoProxy("localhost,127.0.0.1");
+            java.util.List<String[]> defEnvVars = new java.util.ArrayList<>();
+            defEnvVars.add(new String[]{"FOO", "bar"});
+            def.setExtraEnvVars(defEnvVars);
+            def.setExtraCliArgs("--verbose");
+
+            ClaudeProfileStore.saveProfiles(java.util.List.of(def));
+
+            List<ClaudeProfile> loaded = ClaudeProfileStore.getProfiles();
+            ClaudeProfile loadedDef = loaded.get(0);
+            assertTrue(loadedDef.isDefault());
+            assertEquals("sk-api-key-123", loadedDef.getApiKey());
+            assertEquals("oauth-token-xyz", loadedDef.getToken());
+            assertEquals("https://custom.api.example.com", loadedDef.getBaseUrl());
+            assertEquals(ClaudeProfile.ProxyMode.CUSTOM, loadedDef.getProxyMode());
+            assertEquals("http://proxy.example.com:8080", loadedDef.getHttpProxy());
+            assertEquals("https://proxy.example.com:8443", loadedDef.getHttpsProxy());
+            assertEquals("localhost,127.0.0.1", loadedDef.getNoProxy());
+            assertEquals("--verbose", loadedDef.getExtraCliArgs());
+            assertEquals(1, loadedDef.getExtraEnvVars().size());
+            assertArrayEquals(new String[]{"FOO", "bar"}, (Object[]) loadedDef.getExtraEnvVars().get(0));
+        } catch (Exception e) {
+            org.junit.jupiter.api.Assumptions.assumeTrue(false, "NbPreferences not available");
+        }
+    }
+
+    @Test
+    void namedProfile_allFields_roundTrip() {
+        try {
+            ClaudeProfile p = ClaudeProfile.createNamed("Work");
+            p.setApiKey("sk-named-key");
+            p.setToken("named-token");
+            p.setBaseUrl("https://api.work.example.com");
+            p.setProxyMode(ClaudeProfile.ProxyMode.CUSTOM);
+            p.setHttpProxy("http://work-proxy:8080");
+            p.setHttpsProxy("https://work-proxy:8443");
+            p.setNoProxy("internal.example.com");
+            java.util.List<String[]> namedEnvVars = new java.util.ArrayList<>();
+            namedEnvVars.add(new String[]{"ENV_VAR", "value1"});
+            p.setExtraEnvVars(namedEnvVars);
+            p.setExtraCliArgs("--model claude-opus");
+
+            ClaudeProfileStore.saveProfiles(java.util.List.of(ClaudeProfile.createDefault(), p));
+
+            List<ClaudeProfile> loaded = ClaudeProfileStore.getProfiles();
+            assertEquals(2, loaded.size());
+            ClaudeProfile loadedP = loaded.get(1);
+            assertEquals("Work", loadedP.getName());
+            assertEquals("sk-named-key", loadedP.getApiKey());
+            assertEquals("named-token", loadedP.getToken());
+            assertEquals("https://api.work.example.com", loadedP.getBaseUrl());
+            assertEquals(ClaudeProfile.ProxyMode.CUSTOM, loadedP.getProxyMode());
+            assertEquals("http://work-proxy:8080", loadedP.getHttpProxy());
+            assertEquals("https://work-proxy:8443", loadedP.getHttpsProxy());
+            assertEquals("internal.example.com", loadedP.getNoProxy());
+            assertEquals("--model claude-opus", loadedP.getExtraCliArgs());
+            assertEquals(1, loadedP.getExtraEnvVars().size());
+            assertArrayEquals(new String[]{"ENV_VAR", "value1"}, (Object[]) loadedP.getExtraEnvVars().get(0));
+        } catch (Exception e) {
+            org.junit.jupiter.api.Assumptions.assumeTrue(false, "NbPreferences not available");
+        }
+    }
+
     // -------------------------------------------------------------------------
     // resolveStorageDir
     // -------------------------------------------------------------------------