Abu Umamah (radi Allah-u-anhu) narrated that the Messenger of Allah (sal Allahu alaihi wa sallam) said, "Whoever recites Ayat ul-Kursi immediately after each prescribed Prayer, there will be nothing standing between him and his entering Paradise except death." [Nasai, Ibn Hibban, Darimi] I want to ask that we should read ayat al-Kursi at the end of fardh of salah or at the end of complete salah ?
The Hadith you said, says this:
Rasool Allah peace be upon him said, “Whoever recites Aayatul Kursi after every Fard (Fard Salat). Only death is keeping him/her from entering Jannah. (As soon as he/she dies, will enter Jannah) (Nisa’i, Ibne Habban, Ibnelsani A’n Abi Amatah Albahili Radiallah Anhu)
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So it will be best if you say it after the fard of salah.