diff --git a/integrations/google_ai/tests/generators/chat/test_chat_gemini.py b/integrations/google_ai/tests/generators/chat/test_chat_gemini.py
index aced01f02a..83021c2d3e 100644
--- a/integrations/google_ai/tests/generators/chat/test_chat_gemini.py
+++ b/integrations/google_ai/tests/generators/chat/test_chat_gemini.py
@@ -105,7 +105,7 @@ def test_init(self, tools, monkeypatch):
                 tools=tools,
             )
         mock_genai_configure.assert_called_once_with(api_key="test")
-        assert gemini._model_name == "gemini-2.0-flash"
+        assert gemini._model_name == "gemini-2.5-flash"
         assert gemini._generation_config == generation_config
         assert gemini._safety_settings == safety_settings
         assert gemini._tools == tools
@@ -120,7 +120,7 @@ def test_to_dict(self, monkeypatch):
             "type": TYPE,
             "init_parameters": {
                 "api_key": {"env_vars": ["GOOGLE_API_KEY"], "strict": True, "type": "env_var"},
-                "model": "gemini-2.0-flash",
+                "model": "gemini-2.5-flash",
                 "generation_config": None,
                 "safety_settings": None,
                 "streaming_callback": None,
@@ -161,7 +161,7 @@ def test_to_dict_with_param(self, monkeypatch):
             "type": TYPE,
             "init_parameters": {
                 "api_key": {"env_vars": ["GOOGLE_API_KEY"], "strict": True, "type": "env_var"},
-                "model": "gemini-2.0-flash",
+                "model": "gemini-2.5-flash",
                 "generation_config": {
                     "temperature": 0.5,
                     "top_p": 0.5,
@@ -212,7 +212,7 @@ def test_from_dict(self, monkeypatch):
                     "type": TYPE,
                     "init_parameters": {
                         "api_key": {"env_vars": ["GOOGLE_API_KEY"], "strict": True, "type": "env_var"},
-                        "model": "gemini-2.0-flash",
+                        "model": "gemini-2.5-flash",
                         "generation_config": None,
                         "safety_settings": None,
                         "streaming_callback": None,
@@ -221,7 +221,7 @@ def test_from_dict(self, monkeypatch):
                 }
             )
 
-        assert gemini._model_name == "gemini-2.0-flash"
+        assert gemini._model_name == "gemini-2.5-flash"
         assert gemini._generation_config is None
         assert gemini._safety_settings is None
         assert gemini._tools is None
@@ -236,7 +236,7 @@ def test_from_dict_with_param(self, monkeypatch):
                     "type": TYPE,
                     "init_parameters": {
                         "api_key": {"env_vars": ["GOOGLE_API_KEY"], "strict": True, "type": "env_var"},
-                        "model": "gemini-2.0-flash",
+                        "model": "gemini-2.5-flash",
                         "generation_config": {
                             "temperature": 0.5,
                             "top_p": 0.5,
@@ -262,7 +262,7 @@ def test_from_dict_with_param(self, monkeypatch):
                 }
             )
 
-        assert gemini._model_name == "gemini-2.0-flash"
+        assert gemini._model_name == "gemini-2.5-flash"
         assert gemini._generation_config == GenerationConfig(
             candidate_count=1,
             stop_sequences=["stop"],
@@ -286,7 +286,7 @@ def test_serde_in_pipeline(self, monkeypatch):
         tool = Tool(name="name", description="description", parameters={"x": {"type": "string"}}, function=print)
 
         generator = GoogleAIGeminiChatGenerator(
-            model="gemini-2.0-flash",
+            model="gemini-2.5-flash",
             generation_config=GenerationConfig(
                 temperature=0.6,
                 stop_sequences=["stop", "words"],
@@ -308,7 +308,7 @@ def test_serde_in_pipeline(self, monkeypatch):
                     "type": TYPE,
                     "init_parameters": {
                         "api_key": {"env_vars": ["GOOGLE_API_KEY"], "strict": True, "type": "env_var"},
-                        "model": "gemini-2.0-flash",
+                        "model": "gemini-2.5-flash",
                         "generation_config": {
                             "temperature": 0.6,
                             "stop_sequences": ["stop", "words"],
diff --git a/integrations/google_vertex/src/haystack_integrations/components/generators/google_vertex/chat/gemini.py b/integrations/google_vertex/src/haystack_integrations/components/generators/google_vertex/chat/gemini.py
index f3ce7864e1..8abf169cf4 100644
--- a/integrations/google_vertex/src/haystack_integrations/components/generators/google_vertex/chat/gemini.py
+++ b/integrations/google_vertex/src/haystack_integrations/components/generators/google_vertex/chat/gemini.py
@@ -143,7 +143,7 @@ def get_current_weather(
     def __init__(
         self,
         *,
-        model: str = "gemini-1.5-flash",
+        model: str = "gemini-2.5-flash",
         project_id: Optional[str] = None,
         location: Optional[str] = None,
         generation_config: Optional[Union[GenerationConfig, Dict[str, Any]]] = None,
diff --git a/integrations/google_vertex/tests/chat/test_gemini.py b/integrations/google_vertex/tests/chat/test_gemini.py
index 74bb0c8180..8b0fdd67a5 100644
--- a/integrations/google_vertex/tests/chat/test_gemini.py
+++ b/integrations/google_vertex/tests/chat/test_gemini.py
@@ -113,7 +113,7 @@ def test_init(self, mock_vertexai_init, _mock_generative_model, tools):
             tool_config=tool_config,
         )
         mock_vertexai_init.assert_called()
-        assert gemini._model_name == "gemini-1.5-flash"
+        assert gemini._model_name == "gemini-2.5-flash"
         assert gemini._generation_config == generation_config
         assert gemini._safety_settings == safety_settings
         assert gemini._tools == tools
@@ -126,7 +126,7 @@ def test_to_dict(self, _mock_vertexai_init, _mock_generative_model):
         assert gemini.to_dict() == {
             "type": "haystack_integrations.components.generators.google_vertex.chat.gemini.VertexAIGeminiChatGenerator",
             "init_parameters": {
-                "model": "gemini-1.5-flash",
+                "model": "gemini-2.5-flash",
                 "project_id": None,
                 "location": None,
                 "generation_config": None,
@@ -171,7 +171,7 @@ def test_to_dict_with_params(self, _mock_vertexai_init, _mock_generative_model):
         expected_dict = {
             "type": "haystack_integrations.components.generators.google_vertex.chat.gemini.VertexAIGeminiChatGenerator",
             "init_parameters": {
-                "model": "gemini-1.5-flash",
+                "model": "gemini-2.5-flash",
                 "project_id": "TestID123",
                 "location": "TestLocation",
                 "generation_config": {
@@ -225,7 +225,7 @@ def test_from_dict(self, _mock_vertexai_init, _mock_generative_model):
                 ),
                 "init_parameters": {
                     "project_id": None,
-                    "model": "gemini-1.5-flash",
+                    "model": "gemini-2.5-flash",
                     "generation_config": None,
                     "safety_settings": None,
                     "tools": None,
@@ -234,7 +234,7 @@ def test_from_dict(self, _mock_vertexai_init, _mock_generative_model):
             }
         )
 
-        assert gemini._model_name == "gemini-1.5-flash"
+        assert gemini._model_name == "gemini-2.5-flash"
         assert gemini._project_id is None
         assert gemini._safety_settings is None
         assert gemini._tools is None
@@ -254,7 +254,7 @@ def test_from_dict_with_param(self, _mock_vertexai_init, _mock_generative_model)
                 "init_parameters": {
                     "project_id": "TestID123",
                     "location": "TestLocation",
-                    "model": "gemini-1.5-flash",
+                    "model": "gemini-2.5-flash",
                     "generation_config": {
                         "temperature": 0.5,
                         "top_p": 0.5,
@@ -288,7 +288,7 @@ def test_from_dict_with_param(self, _mock_vertexai_init, _mock_generative_model)
             }
         )
 
-        assert gemini._model_name == "gemini-1.5-flash"
+        assert gemini._model_name == "gemini-2.5-flash"
         assert gemini._project_id == "TestID123"
         assert gemini._location == "TestLocation"
         assert gemini._safety_settings == {
@@ -666,7 +666,7 @@ def test_serde_in_pipeline(self):
 
         generator = VertexAIGeminiChatGenerator(
             project_id="TestID123",
-            model="gemini-1.5-flash",
+            model="gemini-2.5-flash",
             generation_config=GenerationConfig(
                 temperature=0.6,
                 stop_sequences=["stop", "words"],
@@ -690,7 +690,7 @@ def test_serde_in_pipeline(self):
                     ),
                     "init_parameters": {
                         "project_id": "TestID123",
-                        "model": "gemini-1.5-flash",
+                        "model": "gemini-2.5-flash",
                         "generation_config": {
                             "temperature": 0.6,
                             "stop_sequences": ["stop", "words"],