diff --git a/csv-validator-ui/src/main/scala/uk/gov/nationalarchives/csv/validator/ui/CsvValidatorUi.scala b/csv-validator-ui/src/main/scala/uk/gov/nationalarchives/csv/validator/ui/CsvValidatorUi.scala
index 213112f7..61965083 100644
--- a/csv-validator-ui/src/main/scala/uk/gov/nationalarchives/csv/validator/ui/CsvValidatorUi.scala
+++ b/csv-validator-ui/src/main/scala/uk/gov/nationalarchives/csv/validator/ui/CsvValidatorUi.scala
@@ -56,8 +56,8 @@ object CsvValidatorUi extends SimpleSwingApplication {
     super.startup(args)
   }
 
-  private val txtCsvFile = new JTextField(30)
-  private val txtCsvSchemaFile = new JTextField(30)
+  private lazy val txtCsvFile = new JTextField(30)
+  private lazy val txtCsvSchemaFile = new JTextField(30)
 
   def top: SJXFrame = new SJXFrame {