When to sit mutawarrikan in prayer
Question

                Is the position of tawarruq to be practiced in the last tashahudd of every prayer or just those consisting of 4 rak’ah?.
Praise be to Allah.Sitting mutawarrikan in 
    prayer is a proven Sunnah of the Prophet  (peace and blessings of Allaah 
    be upon him). Al-Bukhaari narrated from Abu Humayd al-Saa’idi (may Allaah be 
    pleased with him), a description of the prayer of the Prophet  (peace 
    and blessings of Allaah be upon him), in which he said: “And when he sat in 
    the final rak’ah, he put his left foot forward and held the other foot 
    upright, and sat on his behind.” 
Tawarruk or sitting 
    mutawarrikan may be done in different ways: 
1 – The left foot is laid 
    down and the right foot is held upright, and both are held out to the right, 
    with the buttocks on the ground. 
2 – Both feet are laid down 
    and held out to the right side, and the buttocks are on the ground. 
Secondly: 
The scholars (may Allaah 
    have mercy on them) differed as to when one should sit mutawarrikan in 
    prayer. The Hanbalis are of the view that tawarruk should be done in the 
    final tashahhud if there are two tashahhuds in the prayer. But if the prayer 
    has only one tashahhud, such as Fajr prayer or Sunnah prayers that are 
    offered two by two, then one should sit muftarishan (in which one sits on the left foot and the right foot is held upright). 
Al-Bahooti (may Allaah have 
    mercy on him) said in Kashshaaf al-Qinaa’ (1/364): Then he should sit 
    in the second tashahhud of a prayer that consists of three rak’ahs or more 
    mutawarrikan, because of the hadeeth of Abu Humayd, who described him as 
    sitting muftarishan in the first tashahhud and mutawarrikan in the second, 
    This explains the difference between them and this is a description of 
    something additional that should be adopted. In that case it is not Sunnah 
    to sit mutawarrikan, except in a prayer in which there are two tashahhuds, 
    in the last of them. End quote. 
The Shaafa’is are of the 
    view that sitting mutawarrikan is mustahabb in the last tashahhud of all 
    prayers, whether they have two tashahhuds or just one. That is because of 
    the general meaning of the hadeeth of Abu Humayd quoted above, in which it 
    says “when he sat in the last rak’ah.” 
Ibn Hajar (may Allaah have 
    mercy on him) said in Fath al-Baari:  
Al-Shaafa’i also quoted it 
    as evidence that the tashahhud in Fajr prayer is like the final tashahhud in 
    any other prayer, because of the general meaning of his words: “in the final 
    tashahhud.” End quote. 
Al-Nawawi (may Allaah have 
    mercy on him) said in al-Majmoo’ (3/431): Our view is that it is 
    mustahabb to sit muftarishan in the first tashahhud and mutawarrikan in the 
    second. If the prayer is of two rak’ahs then he should sit mutawarrikan. End 
    quote. 
The most correct view is 
    that of the Hanbalis, which was favoured by the scholars of the Standing 
    Committee for Issuing Fatwas. (Shaykh ‘Abd al-‘Azeez ibn Baaz and Shaykh 
    ‘Abd-Allaah ibn Qa’ood). 
See: Fataawa al-Lajnah 
    al-Daa’imah (7/15). 
Ibn Qudaamah (may Allaah 
    have mercy on him) said in al-Mughni (1/318): One should not sit 
    mutawarrikan in any of the sittings in prayer except in the second 
    tashahhud, because of the hadeeth of Waa’il ibn Hujr, which says that when 
    the Prophet  (peace and blessings of Allaah be upon him) sat for the 
    tashahhud “he lay his left foot down and held his right foot upright” and he 
    did not differentiate between the (tashahhud) in which he said the salaam 
    and that in which he did not say the salaam. ‘Aa’ishah said: “The Messenger 
    of Allaah  (peace and blessings of Allaah be upon him) used to recite 
    al-tahiyyah following each two rak’ahs, and he lay his left foot down and 
    held the right foot upright.” Narrated by Muslim. These two (reports) imply 
    that one should sit in the manner described here in every tashahhud. End 
    quote. 
Shaykh Ibn ‘Uthaymeen (may 
    Allaah have mercy on him) was asked in Liqa’ al-Baab il-Maftooh: When 
    should a worshipper sit mutawarrikan in prayer, and in which prayers? 
He replied: Tawarruk is 
    done in the final tashahhud of every prayer that has two tashahhuds, i.e., 
    the last tashahhud in Maghrib, and in ‘Isha’, and in ‘Asr, and in Zuhr. As 
    for the two-rak’ah prayers, such as Fajr, and the regular Sunnah prayers, 
    there is no tawarruk in them. So tawarruk is only in the last tashahhud of 
    every prayer that has two tashahhuds. End quote. 
For more information please 
    see the answer to question no. 13340. 
And Allaah knows best.