diff --git a/CHANGELOG.md b/CHANGELOG.md
index 897340e3..74379d5d 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,3 +1,4 @@
+- Fixed Default profile settings not saving in Tools → Options → Profiles (https://github.com/nbclaudecodegui/NetbeansClaudeCodeGui/issues/31)
 - Fixed "Open with Claude Code" context menu not applying Default profile settings (API key, proxy, Extra CLI args, etc.) (https://github.com/nbclaudecodegui/NetbeansClaudeCodeGui/issues/23)
 - 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)
 - Fixed process start errors and hang timeouts now logged to the IDE log file at SEVERE level
diff --git a/pom.xml b/pom.xml
index ec59dc01..91d144ab 100644
--- a/pom.xml
+++ b/pom.xml
@@ -6,7 +6,7 @@
 
     <groupId>io.github.nbclaudecodegui</groupId>
     <artifactId>netbeans-claude-code-gui</artifactId>
-    <version>0.20.6-SNAPSHOT</version>
+    <version>0.20.7-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 eda7dd48..659af658 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 +59,19 @@ private ClaudeProfileStore() {}
     public static List<ClaudeProfile> getProfiles() {
         List<ClaudeProfile> result = new ArrayList<>();
         ClaudeProfile def = ClaudeProfile.createDefault();
-        def.setExtraCliArgs(ClaudeCodePreferences.getDefaultExtraCliArgs());
+        String defJson = NbPreferences.forModule(ClaudeProfileStore.class)
+                .get(KEY_DEFAULT_PROFILE, null);
+        if (defJson != null) {
+            try {
+                def = MAPPER.readValue(defJson, ClaudeProfile.class);
+            } catch (Exception e) {
+                LOG.warning("Could not parse stored Default profile JSON, using defaults. Cause: " + e);
+                def.setExtraCliArgs(ClaudeCodePreferences.getDefaultExtraCliArgs());
+            }
+        } else {
+            // back-compat: read only extraCliArgs from old key
+            def.setExtraCliArgs(ClaudeCodePreferences.getDefaultExtraCliArgs());
+        }
         result.add(def);
 
         String json = NbPreferences.forModule(ClaudeProfileStore.class)
@@ -117,10 +132,12 @@ public static ClaudeProfile findByName(String name) {
      */
     public static void saveProfiles(List<ClaudeProfile> profiles) {
         List<ClaudeProfile> toSave = new ArrayList<>();
+        ClaudeProfile defaultProfile = null;
         if (profiles != null) {
             for (ClaudeProfile p : profiles) {
                 if (p.isDefault()) {
-                    ClaudeCodePreferences.setDefaultExtraCliArgs(p.getExtraCliArgs());
+                    defaultProfile = p;
+                    ClaudeCodePreferences.setDefaultExtraCliArgs(p.getExtraCliArgs()); // back-compat
                 } else {
                     toSave.add(p);
                 }
@@ -130,6 +147,11 @@ public static void saveProfiles(List<ClaudeProfile> profiles) {
             String json = MAPPER.writeValueAsString(toSave);
             NbPreferences.forModule(ClaudeProfileStore.class)
                     .put(KEY_PROFILES, json);
+            if (defaultProfile != null) {
+                String defJson = MAPPER.writeValueAsString(defaultProfile);
+                NbPreferences.forModule(ClaudeProfileStore.class)
+                        .put(KEY_DEFAULT_PROFILE, defJson);
+            }
             LOG.fine(() -> "Saved " + toSave.size() + " profile(s): " + profileNames(toSave));
         } catch (Exception e) {
             LOG.severe("Could not serialise profiles: " + e.getMessage());
diff --git a/src/test/java/io/github/nbclaudecodegui/settings/ClaudeProfileStoreTest.java b/src/test/java/io/github/nbclaudecodegui/settings/ClaudeProfileStoreTest.java
index 3428db72..ca70cbe6 100644
--- a/src/test/java/io/github/nbclaudecodegui/settings/ClaudeProfileStoreTest.java
+++ b/src/test/java/io/github/nbclaudecodegui/settings/ClaudeProfileStoreTest.java
@@ -228,6 +228,50 @@ void defaultProfile_extraCliArgs_roundTrip() {
         }
     }
 
+    // -------------------------------------------------------------------------
+    // Default profile all-fields round-trip (issue #31)
+    // -------------------------------------------------------------------------
+
+    @Test
+    void defaultProfile_allFields_roundTrip() {
+        try {
+            ClaudeProfile def = ClaudeProfile.createDefault();
+            def.setApiKey("sk-ant-default");
+            def.setExtraCliArgs("--verbose");
+            ClaudeProfileStore.saveProfiles(java.util.List.of(def));
+
+            ClaudeProfile loaded = ClaudeProfileStore.getDefaultProfile();
+            assertTrue(loaded.isDefault());
+            assertEquals("sk-ant-default", loaded.getApiKey(),
+                    "Default profile apiKey must survive save/load");
+            assertEquals("--verbose", loaded.getExtraCliArgs(),
+                    "Default profile extraCliArgs must survive save/load");
+        } 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-ant-work");
+            p.setExtraCliArgs("--model claude-3-5-sonnet-20241022");
+            ClaudeProfileStore.saveProfiles(java.util.List.of(p));
+
+            List<ClaudeProfile> loaded = ClaudeProfileStore.getProfiles();
+            assertEquals(2, loaded.size(), "Expected Default + Work");
+            ClaudeProfile work = loaded.get(1);
+            assertEquals("Work", work.getName());
+            assertEquals("sk-ant-work", work.getApiKey(),
+                    "Named profile apiKey must survive save/load");
+            assertEquals("--model claude-3-5-sonnet-20241022", work.getExtraCliArgs(),
+                    "Named profile extraCliArgs must survive save/load");
+        } catch (Exception e) {
+            org.junit.jupiter.api.Assumptions.assumeTrue(false, "NbPreferences not available");
+        }
+    }
+
     // -------------------------------------------------------------------------
     // extraCliArgs serialization round-trip
     // -------------------------------------------------------------------------