diff --git a/core/src/main/kotlin/net/corda/core/transactions/TransactionBuilder.kt b/core/src/main/kotlin/net/corda/core/transactions/TransactionBuilder.kt
index a3a6c5cff8..0adfb19ef1 100644
--- a/core/src/main/kotlin/net/corda/core/transactions/TransactionBuilder.kt
+++ b/core/src/main/kotlin/net/corda/core/transactions/TransactionBuilder.kt
@@ -164,7 +164,7 @@ open class TransactionBuilder(
 
     /** A default notary must be specified during builder construction to use this method */
     fun addOutputState(state: ContractState): Int {
-        checkNotNull(notary) { "Need to specify a Notary for the state, or set a default one on TransactionBuilder initialisation" }
+        checkNotNull(notary) { "Need to specify a notary for the state, or set a default one on TransactionBuilder initialisation" }
         return addOutputState(state, notary!!)
     }