diff --git a/constants/constants.js b/constants/constants.js
index 3c9f7f2..9ed4a5c 100644
--- a/constants/constants.js
+++ b/constants/constants.js
@@ -123,7 +123,9 @@ const discounts = {
 };
 const DISCOUNT_PLANS = process.env.DISCOUNT_PLANS.split(',').map(planName => planName.trim()) || [];
 
-const CUSTOM_FEES_PREFIXES = process.env.CUSTOM_FEES_PREFIXES.split(',').map(prefix => prefix.trim()) || [];
+const CUSTOM_FEES_PREFIXES = process.env.CUSTOM_FEES_PREFIXES.split(',')
+    .map(prefix => prefix.trim())
+    .filter(prefix => prefix && prefix.length ? prefix.length > 0 : false) || [];
 
 const UNPAID_FEE_STATUS = 'not_paid';