Should a late-comer joining the Jamaat recite Thana?

Answer

If it is a Sirri Salaat (Zuhr or Asr), or if you join in the third or fourth raka'at of Fardh which is Sirri, then after Takbir Tahrimah recite Thana. If it is a Jahri Salaat and the Imaam is reciting Qiraa't, then don't recite Thana. Recite it in the first raka't after the Imaam has ended the Salaat. In the first instance where you have recited Thana upon joining in a Sirri Salaat, repeat Thana when you fulfil your missed raka'ts.