diff --git a/lambda/ham_listener_put/__init__.py b/lambda/ham_listener_put/__init__.py
index fb9c061..1a3767e 100644
--- a/lambda/ham_listener_put/__init__.py
+++ b/lambda/ham_listener_put/__init__.py
@@ -16,6 +16,8 @@ import es
 
 # Setup SNS
 
+TOPIC = config_handler.get("SNS","TOPIC")
+
 def set_connection_header(request, operation_name, **kwargs):
     request.headers['Connection'] = 'keep-alive'
 
@@ -28,7 +30,7 @@ def post(payload):
         f.write(json.dumps(payload).encode('utf-8'))
     payload = base64.b64encode(compressed.getvalue()).decode("utf-8")
     sns.publish(
-                TopicArn=config_handler.get("SNS","TOPIC"),
+                TopicArn=TOPIC,
                 Message=payload
     )
 
diff --git a/lambda/ham_put_api/__init__.py b/lambda/ham_put_api/__init__.py
index fad5f1b..cdb251c 100644
--- a/lambda/ham_put_api/__init__.py
+++ b/lambda/ham_put_api/__init__.py
@@ -13,6 +13,8 @@ def set_connection_header(request, operation_name, **kwargs):
 sns = boto3.client("sns",region_name="us-east-1")
 sns.meta.events.register('request-created.sns', set_connection_header)
 
+TOPIC = config_handler.get("HAM_SNS","TOPIC")
+
 def check_fields_are_number(field, telemetry):
     if type(telemetry[field]) != float and type(telemetry[field]) != int:
         return (False, f"{field} should not be a float")
@@ -47,7 +49,7 @@ def telemetry_hide_filter(telemetry):
 
 def post(payload):
     sns.publish(
-                TopicArn=config_handler.get("HAM_SNS","TOPIC"),
+                TopicArn=TOPIC,
                 Message=json.dumps(payload)
     )
 
diff --git a/lambda/sns_to_mqtt/__init__.py b/lambda/sns_to_mqtt/__init__.py
index 4ce626a..61cd426 100644
--- a/lambda/sns_to_mqtt/__init__.py
+++ b/lambda/sns_to_mqtt/__init__.py
@@ -13,6 +13,10 @@ import sys
 import uuid
 import config_handler
 
+MQTT_ID = config_handler.get("MQTT","ID")
+MQTT_PREFIX = config_handler.get("MQTT","PREFIX")
+MQTT_BATCH = config_handler.get("MQTT","BATCH")
+
 client = mqtt.Client(transport="websockets")
 
 connected_flag = False
@@ -120,18 +124,18 @@ def lambda_handler(event, context):
                 
                 body = json.dumps(payload)
 
-                serial = payload[config_handler.get("MQTT","ID")]
+                serial = payload[MQTT_ID]
                 while not connected_flag:
                     time.sleep(0.01) # wait until connected
                 client.publish(
-                    topic=f'{config_handler.get("MQTT","PREFIX")}/{serial}',
+                    topic=f'{MQTT_PREFIX}/{serial}',
                     payload=body,
                     qos=0,
                     retain=False
                 )
                 if serial not in cache: # low bandwidth feeds with just the first packet
                     client.publish(
-                        topic=f'{config_handler.get("MQTT","PREFIX")}-new/{serial}',
+                        topic=f'{MQTT_PREFIX}-new/{serial}',
                         payload=body,
                         qos=0,
                         retain=False
@@ -141,7 +145,7 @@ def lambda_handler(event, context):
                     while len(cache) > MAX_CACHE:
                         del cache[next(iter(cache))]
             client.publish(
-                topic=config_handler.get("MQTT","BATCH"),
+                topic=MQTT_BATCH,
                 payload=json.dumps(payloads),
                 qos=0,
                 retain=False
diff --git a/lambda/sonde_api_to_iot_core/__init__.py b/lambda/sonde_api_to_iot_core/__init__.py
index 5557812..d5ed63a 100644
--- a/lambda/sonde_api_to_iot_core/__init__.py
+++ b/lambda/sonde_api_to_iot_core/__init__.py
@@ -22,6 +22,8 @@ import config_handler
 logs = boto3.client('logs')
 sequenceToken = None
 
+TOPIC = config_handler.get("SNS","TOPIC")
+
 def set_connection_header(request, operation_name, **kwargs):
     request.headers['Connection'] = 'keep-alive'
 
@@ -368,7 +370,7 @@ def post(payload):
         f.write(json.dumps(payload).encode('utf-8'))
     payload = base64.b64encode(compressed.getvalue()).decode("utf-8")
     sns.publish(
-                TopicArn=config_handler.get("SNS","TOPIC"),
+                TopicArn=TOPIC,
                 Message=payload
     )
 
diff --git a/lambda/station_api_to_iot_core/__init__.py b/lambda/station_api_to_iot_core/__init__.py
index fa28e37..afc720a 100644
--- a/lambda/station_api_to_iot_core/__init__.py
+++ b/lambda/station_api_to_iot_core/__init__.py
@@ -14,6 +14,8 @@ CALLSIGN_BLOCK_LIST = ["CHANGEME_RDZTTGO"]
 
 import es
 
+TOPIC = config_handler.get("SNS","TOPIC")
+
 # Setup SNS
 
 def set_connection_header(request, operation_name, **kwargs):
@@ -28,7 +30,7 @@ def post(payload):
         f.write(json.dumps(payload).encode('utf-8'))
     payload = base64.b64encode(compressed.getvalue()).decode("utf-8")
     sns.publish(
-                TopicArn=config_handler.get("SNS","TOPIC"),
+                TopicArn=TOPIC,
                 Message=payload
     )
 
diff --git a/lambda/ttn_helium/__init__.py b/lambda/ttn_helium/__init__.py
index 5fe53d4..3dae54c 100644
--- a/lambda/ttn_helium/__init__.py
+++ b/lambda/ttn_helium/__init__.py
@@ -7,6 +7,8 @@ from email.utils import parsedate
 import os
 import config_handler
 
+TOPIC = config_handler.get("HAM_SNS","TOPIC")
+
 HELIUM_GW_VERSION = "2023.10.14"
 
 # Mappings between input (Helium) field names, and field names fed into SondeHub-Amateur
@@ -47,7 +49,7 @@ sns.meta.events.register('request-created.sns', set_connection_header)
 
 def post(payload):
     sns.publish(
-                TopicArn=config_handler.get("HAM_SNS","TOPIC"),
+                TopicArn=TOPIC,
                 Message=json.dumps(payload)
     )