diff --git a/core/api.txt b/core/api.txt
index 14736c3556..e149704e89 100644
--- a/core/api.txt
+++ b/core/api.txt
@@ -1347,6 +1347,8 @@ ion-radio,part,mark
 ion-radio-group,none
 ion-radio-group,prop,allowEmptySelection,boolean,false,false,false
 ion-radio-group,prop,compareWith,((currentValue: any, compareValue: any) => boolean) | null | string | undefined,undefined,false,false
+ion-radio-group,prop,errorText,string | undefined,undefined,false,false
+ion-radio-group,prop,helperText,string | undefined,undefined,false,false
 ion-radio-group,prop,name,string,this.inputId,false,false
 ion-radio-group,prop,value,any,undefined,false,false
 ion-radio-group,event,ionChange,RadioGroupChangeEventDetail<any>,true