diff --git a/backend/routes/generate_code.py b/backend/routes/generate_code.py
index d59b8d1..580df4d 100644
--- a/backend/routes/generate_code.py
+++ b/backend/routes/generate_code.py
@@ -12,7 +12,8 @@ from prompts import assemble_imported_code_prompt, assemble_prompt
 from access_token import validate_access_token
 from datetime import datetime
 import json
-from routes.logging_utils import send_to_saas_backend
+from routes.logging_utils import PaymentMethod, send_to_saas_backend
+from routes.saas_utils import does_user_have_subscription_credits
 
 from utils import pprint_prompt  # type: ignore
 
@@ -62,6 +63,9 @@ async def stream_code(websocket: WebSocket):
         generated_code_config = params["generatedCodeConfig"]
     print(f"Generating {generated_code_config} code")
 
+    # Track how this generation is being paid for
+    payment_method: PaymentMethod = PaymentMethod.UNKNOWN
+
     # Get the OpenAI API key from the request. Fall back to environment variable if not provided.
     # If neither is provided, we throw an error.
     openai_api_key = None
@@ -69,6 +73,7 @@ async def stream_code(websocket: WebSocket):
         print("Access code - using platform API key")
         res = await validate_access_token(params["accessCode"])
         if res["success"]:
+            payment_method = PaymentMethod.ACCESS_CODE
             openai_api_key = os.environ.get("PLATFORM_OPENAI_API_KEY")
         else:
             await websocket.send_json(
@@ -79,10 +84,32 @@ async def stream_code(websocket: WebSocket):
             )
             return
     else:
+        auth_token = params.get("authToken")
+        if auth_token:
+            # TODO: Rename does_user_have_subscription_credits
+            res = await does_user_have_subscription_credits(auth_token)
+            if res.status == "not_subscriber":
+                # Keep going for non-subscriber users
+                pass
+            elif res.status == "subscriber_has_credits":
+                payment_method = PaymentMethod.SUBSCRIPTION
+                openai_api_key = os.environ.get("PLATFORM_OPENAI_API_KEY")
+            elif res.status == "subscriber_has_no_credits":
+                return await throw_error(
+                    "Your subscription has run out of monthly credits. Contact support and we can add more credits to your account for free."
+                )
+            else:
+                return await throw_error("Unknown error occurred. Contact support.")
+
+        else:
+            # Log but keep going for users
+            print("Missing auth token")
+
         if params["openAiApiKey"]:
             openai_api_key = params["openAiApiKey"]
+            payment_method = PaymentMethod.OPENAI_API_KEY
             print("Using OpenAI API key from client-side settings dialog")
-        else:
+        elif not openai_api_key:
             openai_api_key = os.environ.get("OPENAI_API_KEY")
             if openai_api_key:
                 print("Using OpenAI API key from environment variable")
@@ -238,7 +265,12 @@ async def stream_code(websocket: WebSocket):
     if IS_PROD:
         # Catch any errors from sending to SaaS backend and continue
         try:
-            await send_to_saas_backend(prompt_messages, completion, params["authToken"])
+            await send_to_saas_backend(
+                prompt_messages,
+                completion,
+                payment_method=payment_method,
+                auth_token=params["authToken"],
+            )
         except Exception as e:
             print("Error sending to SaaS backend", e)
 
diff --git a/backend/routes/logging_utils.py b/backend/routes/logging_utils.py
index b13ce39..8d16558 100644
--- a/backend/routes/logging_utils.py
+++ b/backend/routes/logging_utils.py
@@ -1,3 +1,4 @@
+from enum import Enum
 import httpx
 from openai.types.chat import ChatCompletionMessageParam
 from typing import List
@@ -6,20 +7,30 @@ import json
 from config import IS_PROD
 
 
+class PaymentMethod(Enum):
+    LEGACY = "legacy"
+    UNKNOWN = "unknown"
+    OPENAI_API_KEY = "openai_api_key"
+    SUBSCRIPTION = "subscription"
+    ACCESS_CODE = "access_code"
+
+
 async def send_to_saas_backend(
     prompt_messages: List[ChatCompletionMessageParam],
     completion: str,
+    payment_method: PaymentMethod,
     auth_token: str | None = None,
 ):
     if IS_PROD:
         async with httpx.AsyncClient() as client:
-            url = "https://screenshot-to-code-saas.onrender.com/generations/store"
-            # url = "http://localhost:8001/generations/store"
+            # url = "https://screenshot-to-code-saas.onrender.com/generations/store"
+            url = "http://localhost:8001/generations/store"
 
             data = json.dumps(
                 {
                     "prompt": json.dumps(prompt_messages),
                     "completion": completion,
+                    "payment_method": payment_method.value,
                 }
             )
 
diff --git a/backend/routes/saas_utils.py b/backend/routes/saas_utils.py
new file mode 100644
index 0000000..94ce340
--- /dev/null
+++ b/backend/routes/saas_utils.py
@@ -0,0 +1,23 @@
+import httpx
+from pydantic import BaseModel
+
+
+class SubscriptionCreditsResponse(BaseModel):
+    status: str
+
+
+async def does_user_have_subscription_credits(
+    auth_token: str,
+):
+    async with httpx.AsyncClient() as client:
+        # url = "https://screenshot-to-code-saas.onrender.com/credits/has_credits"
+        url = "http://localhost:8001/credits/has_credits"
+
+        headers = {
+            "Content-Type": "application/json",
+            "Authorization": f"Bearer {auth_token}",
+        }
+
+        response = await client.post(url, headers=headers)
+        parsed_response = SubscriptionCreditsResponse.parse_obj(response.json())
+        return parsed_response