diff --git a/internal/ethapi/simulate.go b/internal/ethapi/simulate.go
index 307e7d7ec8..280156bb77 100644
--- a/internal/ethapi/simulate.go
+++ b/internal/ethapi/simulate.go
@@ -167,12 +167,7 @@ func (mc *multicall) execute(ctx context.Context, opts mcOpts) ([]mcBlockResult,
 			if err := mc.sanitizeCall(&call, state, &gasUsed, blockContext); err != nil {
 				return nil, err
 			}
-			// Default to dynamic-fee transaction type.
-			type2 := true
-			if call.GasPrice != nil {
-				type2 = false
-			}
-			tx := call.ToTransaction(type2)
+			tx := call.ToTransaction()
 			txes[i] = tx
 			// TODO: repair log block hashes post execution.
 			vmConfig := &vm.Config{
diff --git a/internal/ethapi/transaction_args.go b/internal/ethapi/transaction_args.go
index afc866d0e9..906210f957 100644
--- a/internal/ethapi/transaction_args.go
+++ b/internal/ethapi/transaction_args.go
@@ -366,7 +366,9 @@ func (args *TransactionArgs) toTransaction(type2 bool) *types.Transaction {
 }
 
 // ToTransaction converts the arguments to a transaction.
+// It defaults to a dynamic fee transaction unless legacy gas price
+// is explicitly provided.
 // This assumes that setDefaults has been called.
-func (args *TransactionArgs) ToTransaction(type2 bool) *types.Transaction {
-	return args.toTransaction(type2)
+func (args *TransactionArgs) ToTransaction() *types.Transaction {
+	return args.toTransaction(args.GasPrice == nil)
 }