diff --git a/backend/address2UPRN/main.py b/backend/address2UPRN/main.py
index 8d1ba21d..0aedd082 100644
--- a/backend/address2UPRN/main.py
+++ b/backend/address2UPRN/main.py
@@ -10,11 +10,13 @@ from typing import Set
 import json
 import requests
 from uuid import UUID
+import uuid
 from backend.app.db.functions.tasks.Tasks import SubTaskInterface
+from utils.s3 import save_csv_to_s3
+from datetime import datetime
 
 logger = setup_logger()
 
-
 EPC_AUTH_TOKEN = os.getenv(
     "EPC_AUTH_TOKEN",
 )
@@ -502,6 +504,46 @@ def resolve_uprns_for_postcode_group(
     )
 
 
+def save_results_to_s3(
+    results_df: pd.DataFrame, task_id: str, sub_task_id: str, bucket_name: str = None
+) -> bool:
+    """
+    Save results DataFrame to S3 as CSV.
+
+    :param results_df: The DataFrame containing results
+    :param task_id: The task ID (used for file naming)
+    :param bucket_name: The S3 bucket name (defaults to env variable)
+    :return: True if successful, False otherwise
+    """
+    if bucket_name is None:
+        bucket_name = os.getenv("S3_BUCKET_NAME")
+
+    if not bucket_name:
+        logger.error(
+            "S3 bucket name not provided and S3_BUCKET_NAME environment variable not set"
+        )
+        return False
+
+    try:
+        # Create a filename with the task ID
+        file_name = f"{datetime.now().isoformat()}_{str(uuid.uuid4())[:8]}"
+        file_key = f"ara_raw_outputs/{task_id}/{sub_task_id}/{file_name}.csv"
+
+        # Save to S3
+        success = save_csv_to_s3(results_df, bucket_name, file_key)
+
+        if success:
+            logger.info(f"Successfully saved results to s3://{bucket_name}/{file_key}")
+            return True
+        else:
+            logger.error(f"Failed to save results to S3")
+            return False
+
+    except Exception as e:
+        logger.error(f"Error saving results to S3: {str(e)}")
+        return False
+
+
 def test(a, b):
     assert a == b, f"erorr: {a}{type(a)} != {b}: {type(b)}"
 
@@ -760,7 +802,12 @@ def handler(event, context, local=False):
 
             # Create results DataFrame
             result_df = pd.DataFrame(results_data)
-            logger.info(f"Created results DataFrame with {len(result_df)} rows")
+
+            # Save results to S3
+            try:
+                save_results_to_s3(result_df, str(task_id), str(subtask_id))
+            except Exception as s3_error:
+                logger.error(f"Failed to save results to S3: {s3_error}")
 
             results.append(
                 {
diff --git a/backend/postcode_splitter/main.py b/backend/postcode_splitter/main.py
index 943435b9..73a79d2c 100644
--- a/backend/postcode_splitter/main.py
+++ b/backend/postcode_splitter/main.py
@@ -164,6 +164,12 @@ def handler(event, context, local=False):
             # just do 5 well we are testing, sqs connection
             if local:
                 df = df.head(5)
+
+            # TODO: DELETE ME, if you see this in the PR.
+            # TODO: DELETE ME, if you see this in the PR.
+            # TODO: DELETE ME, if you see this in the PR.
+            df = df.head(5)
+
             logger.info(f"CSV loaded: {len(df)} rows, {len(df.columns)} columns")
 
             # Sanitise postcodes
diff --git a/infrastructure/terraform/shared/main.tf b/infrastructure/terraform/shared/main.tf
index 5e189dc9..4ec57c3e 100644
--- a/infrastructure/terraform/shared/main.tf
+++ b/infrastructure/terraform/shared/main.tf
@@ -305,6 +305,21 @@ module "address2uprn_registry" {
 
 }
 
+# S3 policy for postcode splitter to read from retrofit data bucket
+module "address2uprn_s3_read_and_write" {
+  source = "../modules/s3_iam_policy"
+
+  policy_name        = "Address2UPRNReadandWriteS3"
+  policy_description = "Allow address2uprn Lambda to read and write from retrofit-data bucket"
+  bucket_arns        = ["arn:aws:s3:::retrofit-data-${var.stage}"]
+  actions            = ["s3:GetObject", "s3:ListBucket", "s3:PutObject"]
+  resource_paths     = ["/*"]
+}
+
+output "postcode_splitter_s3_read_arn" {
+  value = module.postcode_splitter_s3_read.policy_arn
+}
+
 ################################################
 # Condition ETL – Lambda ECR
 ################################################
diff --git a/utils/s3.py b/utils/s3.py
index 2e67d4f0..0e79c26b 100644
--- a/utils/s3.py
+++ b/utils/s3.py
@@ -8,7 +8,6 @@ from botocore.exceptions import NoCredentialsError, PartialCredentialsError
 
 logger = setup_logger()
 
-
 def read_from_s3(bucket_name, s3_file_name):
     """
     Read an object from s3. Decoding of the data is left for outside of this function