Short answer
In the Hanafi school the wajib acts include reciting al-Fatiha, adding a surah in the first two rakats of fard, stillness in each position, the first sitting and the tashahhud in both sittings, the word as-salam, qunoot in witr, the Eid takbirs, and loud or silent recitation in its place. Missing one by mistake is fixed with sajdah sahw.
A wajib act is below fard: leaving it does not void the prayer, but forgetting it requires sajdah sahw, and leaving it deliberately makes the prayer deficient so that it must be repeated (i'adah) within its time. The list is drawn from Nur al-Idah and al-Durr al-Mukhtar.
Other madhhabs
- Shafi'i
- There is no wajib level. Acts are pillars or sunnahs; a few key sunnahs (the first tashahhud and the qunoot of Fajr) call for sajdah sahw if missed.
- Maliki
- Acts are obligations or sunnahs; missing confirmed sunnahs is made up with sajdah sahw.
- Hanbali
- There is a wajib level, but its list differs: the transition takbirs, the tasbih in ruku and sajdah, "sami'allahu liman hamidah", "rabbana lakal hamd", "rabbighfir li" between the sajdahs, and the first tashahhud with its sitting.
Explanation
The Hanafi school sorts the acts of salah into four levels: conditions and fard acts (without which the prayer is invalid), wajib acts, sunnahs and etiquettes. The fard acts are listed in the conditions and fard acts of salah. The wajib acts are:
- Reciting al-Fatiha in every rakah, except the third and fourth of a fard prayer, where it is sunnah.
- Adding a surah or three short verses after al-Fatiha in the first two rakats of fard, and in every rakah of witr, sunnah and nafl.
- Reciting al-Fatiha before the surah, and not repeating it before the surah.
- Placing the nose with the forehead in sajdah.
- Doing the second sajdah of each rakah before moving on.
- Stillness (tuma'ninah) in ruku, sajdah, standing after ruku and sitting between the sajdahs.
- The first sitting in a three or four rakah prayer.
- Reciting the tashahhud in both sittings.
- Standing for the third rakah straight after the first tashahhud, without adding the salawat.
- The word "as-salam" at the end, to the right and left.
- The qunoot in witr.
- The extra takbirs of the two Eid prayers.
- Reciting aloud where the imam must, and silently where all must.
- For the follower, following the imam and staying silent while he recites.
If you miss one: by mistake, do sajdah sahw at the end. On purpose, the prayer is deficient and should be repeated in its time. The man who prayed hastily was told three times by the Prophet ﷺ to go back and pray, because he did not keep still in his ruku and sajdah.
Specific cases: forgetting the first tashahhud, forgetting the surah after al-Fatiha and forgetting the qunoot.
The evidence
Sahih al-Bukhari 756
Sahih... لا صلاة لمن لم يقرأ بفاتحة الكتاب ...
"There is no prayer for one who does not recite the Opening of the Book."
Al-Fatiha is required in the prayer; the Hanafi school places it at the wajib level.
Sahih al-Bukhari 757
Sahih... ثم اركع حتى تطمئن راكعا ...
"Then bow until you are still in ruku, then rise until you stand straight, then prostrate until you are still in prostration."
Stillness in each position is required.
Where the ruling is recorded
- Nur al-Idah with Maraqi al-Falah, Chapter on the wajibs of the prayer. The list of the wajib acts of salah.
- al-Durr al-Mukhtar, Kitab al-Salah, chapter on the description of the prayer. The wajibs, and that a prayer with a wajib left deliberately must be repeated.
Checked by our team. For a more accurate answer to your own situation, consult a scholar. Quran translation by Sahih International. Hadith Arabic from the standard editions of the six books and the Muwatta, with gradings as recorded there; the English is our own rendering. Spotted a mistake? Tell us.