diff --git a/litellm/llms/perplexity/chat/transformation.py b/litellm/llms/perplexity/chat/transformation.py
index 354f7692fd5..685f85d04e9 100644
--- a/litellm/llms/perplexity/chat/transformation.py
+++ b/litellm/llms/perplexity/chat/transformation.py
@@ -30,6 +30,22 @@ class PerplexityChatConfig(OpenAIGPTConfig):
         dynamic_api_key = api_key or get_secret_str("PERPLEXITYAI_API_KEY") or get_secret_str("PERPLEXITY_API_KEY")
         return api_base, dynamic_api_key
 
+    def validate_environment(
+        self,
+        headers: dict,  # mutable-ok: matches the base chat transform signature
+        model: str,
+        messages: list[AllMessageValues],  # mutable-ok: matches the base chat transform signature
+        optional_params: dict,  # mutable-ok: matches the base chat transform signature
+        litellm_params: dict,  # mutable-ok: matches the base chat transform signature
+        api_key: str | None = None,
+        api_base: str | None = None,
+    ) -> dict:  # mutable-ok: matches the base chat transform signature
+        if not any(name.lower() == "x-pplx-integration" for name in headers):
+            headers["X-Pplx-Integration"] = "litellm"
+        return super().validate_environment(
+            headers, model, messages, optional_params, litellm_params, api_key, api_base
+        )
+
     def get_supported_openai_params(self, model: str) -> list:
         """
         Perplexity supports a subset of OpenAI params
diff --git a/tests/test_litellm/llms/perplexity/chat/test_perplexity_chat_transformation.py b/tests/test_litellm/llms/perplexity/chat/test_perplexity_chat_transformation.py
index 29d185b686d..5e835e44917 100644
--- a/tests/test_litellm/llms/perplexity/chat/test_perplexity_chat_transformation.py
+++ b/tests/test_litellm/llms/perplexity/chat/test_perplexity_chat_transformation.py
@@ -5,12 +5,10 @@ Tests the response transformation to extract citation tokens and search queries
 from Perplexity API responses.
 """
 
-from unittest.mock import Mock
-
+import httpx
 import pytest
 
 # Add the project root to Python path
-
 from litellm import ModelResponse
 from litellm.llms.perplexity.chat.transformation import PerplexityChatConfig
 from litellm.types.utils import Usage
@@ -19,6 +17,28 @@ from litellm.types.utils import Usage
 class TestPerplexityChatTransformation:
     """Test suite for Perplexity chat transformation functionality."""
 
+    @pytest.mark.parametrize(
+        ("headers", "expected"),
+        [({}, "litellm"), ({"x-pplx-integration": "custom"}, "custom")],
+    )
+    def test_integration_header_default_is_caller_overridable(
+        self, headers: dict[str, str], expected: str
+    ):
+        validated_headers = PerplexityChatConfig().validate_environment(
+            headers=headers,
+            model="sonar",
+            messages=[],
+            optional_params={},
+            litellm_params={},
+        )
+        request = httpx.Request(
+            "POST",
+            "https://api.perplexity.ai/chat/completions",
+            headers=validated_headers,
+        )
+
+        assert request.headers.get_list("x-pplx-integration") == [expected]
+
     def test_enhance_usage_with_citation_tokens(self):
         """Test extraction of citation tokens from API response."""
         config = PerplexityChatConfig()