Sayyed Mohammad Al-Musawi, Sayyed Mohammad al-Musawi is originally from Iraq and heads up the World Ahlul Bayt Islamic League in London. Other than being involved in various humanitarian projects, he frequently responds to... Answered 1 year ago

Joining a congregation prayer is allowed in every Rak'ah till before the Imam of Jama'ah raises his head from Rokoo'. If you join during Qiyaam (Standing) or Rokoo', it will be counted for you as a Rak'ah.

We are not allowed to join congregation prayer after Rokoo' except in the last Rak'ah just to get the reward of the congregation prayer but it will not be counted as a Rak'ah.