diff --git a/client/src/hooks/useNewConvo.ts b/client/src/hooks/useNewConvo.ts
index 22ea5f327c..63b442b83a 100644
--- a/client/src/hooks/useNewConvo.ts
+++ b/client/src/hooks/useNewConvo.ts
@@ -252,18 +252,20 @@ const useNewConvo = (index = 0) => {
       };
 
       let preset = _preset;
-      const defaultModelSpec = getDefaultModelSpec(startupConfig);
+      const result = getDefaultModelSpec(startupConfig);
+      const defaultModelSpec = result?.default ?? result?.last;
       if (
         !preset &&
         startupConfig &&
         (startupConfig.modelSpecs?.prioritize === true ||
-          (startupConfig.interface?.modelSelect ?? true) !== true) &&
+          (startupConfig.interface?.modelSelect ?? true) !== true ||
+          (result?.last != null && Object.keys(_template).length === 0)) &&
         defaultModelSpec
       ) {
         preset = getModelSpecPreset(defaultModelSpec);
       }
 
-      if (conversation.conversationId === 'new' && !modelsData) {
+      if (conversation.conversationId === Constants.NEW_CONVO && !modelsData) {
         const filesToDelete = Array.from(files.values())
           .filter(
             (file) =>
diff --git a/client/src/routes/ChatRoute.tsx b/client/src/routes/ChatRoute.tsx
index d81cbc075c..240b5583b9 100644
--- a/client/src/routes/ChatRoute.tsx
+++ b/client/src/routes/ChatRoute.tsx
@@ -66,7 +66,8 @@ export default function ChatRoute() {
     }
 
     if (conversationId === Constants.NEW_CONVO && endpointsQuery.data && modelsQuery.data) {
-      const spec = getDefaultModelSpec(startupConfig);
+      const result = getDefaultModelSpec(startupConfig);
+      const spec = result?.default ?? result?.last;
       logger.log('conversation', 'ChatRoute, new convo effect', conversation);
       newConversation({
         modelsData: modelsQuery.data,
@@ -90,7 +91,8 @@ export default function ChatRoute() {
       assistantListMap[EModelEndpoint.assistants] &&
       assistantListMap[EModelEndpoint.azureAssistants]
     ) {
-      const spec = getDefaultModelSpec(startupConfig);
+      const result = getDefaultModelSpec(startupConfig);
+      const spec = result?.default ?? result?.last;
       logger.log('conversation', 'ChatRoute new convo, assistants effect', conversation);
       newConversation({
         modelsData: modelsQuery.data,
diff --git a/client/src/utils/endpoints.ts b/client/src/utils/endpoints.ts
index 60585132d4..c98680843a 100644
--- a/client/src/utils/endpoints.ts
+++ b/client/src/utils/endpoints.ts
@@ -176,11 +176,17 @@ export function getConvoSwitchLogic(params: ConversationInitParams): InitiatedTe
   };
 }
 
-/** Gets the default spec by order.
- *
- * First, the admin defined default, then last selected spec, followed by first spec
+/**
+ * Gets default model spec from config and user preferences.
+ * Priority: admin default → last selected → first spec (when prioritize=true or modelSelect disabled).
+ * Otherwise: admin default or last conversation spec.
  */
-export function getDefaultModelSpec(startupConfig?: t.TStartupConfig) {
+export function getDefaultModelSpec(startupConfig?: t.TStartupConfig):
+  | {
+      default?: t.TModelSpec;
+      last?: t.TModelSpec;
+    }
+  | undefined {
   const { modelSpecs, interface: interfaceConfig } = startupConfig ?? {};
   const { list, prioritize } = modelSpecs ?? {};
   if (!list) {
@@ -190,9 +196,9 @@ export function getDefaultModelSpec(startupConfig?: t.TStartupConfig) {
   if (prioritize === true || !interfaceConfig?.modelSelect) {
     const lastSelectedSpecName = localStorage.getItem(LocalStorageKeys.LAST_SPEC);
     const lastSelectedSpec = list?.find((spec) => spec.name === lastSelectedSpecName);
-    return defaultSpec || lastSelectedSpec || list?.[0];
+    return { default: defaultSpec || lastSelectedSpec || list?.[0] };
   } else if (defaultSpec) {
-    return defaultSpec;
+    return { default: defaultSpec };
   }
   const lastConversationSetup = JSON.parse(
     localStorage.getItem(LocalStorageKeys.LAST_CONVO_SETUP + '_0') ?? '{}',
@@ -200,7 +206,7 @@ export function getDefaultModelSpec(startupConfig?: t.TStartupConfig) {
   if (!lastConversationSetup.spec) {
     return;
   }
-  return list?.find((spec) => spec.name === lastConversationSetup.spec);
+  return { last: list?.find((spec) => spec.name === lastConversationSetup.spec) };
 }
 
 export function getModelSpecPreset(modelSpec?: t.TModelSpec) {