Forbidden to delay prayer until the time for it ends
10-1-2015 | IslamWeb
Question:
Assalaamu'alaykum, I asked a question here a few days ago regarding the prayer and was referred to other fatwas on the same topic. While they were enlightening unfortunately they didn't answer my specific question which was: When speaking of the punishment of 'delaying' the prayer, is delaying considered praying outside of the fixed prayer time (i.e. the beginning of the next prayer) or at the end of the that prayer time. I was always confused about this as although delaying the prayer in it's time is understandably discouraged, you're still praying within it's fixed time-frame. So I thought perhaps the punishment was referring to delaying outside of it's fixed time-frame (into the start of the next prayer). I will be very grateful if you could clear this issue for me. Jazaak'Allah Kheiran.
Answer:
All perfect praise be to Allaah, The Lord of the Worlds. I testify that there is none worthy of worship except Allaah, and that Muhammad, sallallaahu ‘alayhi wa sallam, is His slave and Messenger.
What is prohibited is to deliberately delay the prayer without a valid excuse until the end of its due time and the beginning of the time of the following prayer, such as delaying the Thuhr prayer until the ‘Asr prayer is due. The Prophet, sallallaahu ‘alayhi wa sallam, said: “Negligence is when one does not offer the prayer until the time of the next prayer occurs.” [Muslim]
The same applies to delaying a prayer until the end of its time even if the following prayer is not yet due like when delaying Fajr prayer until after sunrise. For more benefit, please refer to Fataawa 82253, 90926 and 248833.
As for delaying the prayer until the end of its time before the time is over, it is not prohibited, but it is either disliked or contrary to what is best. The Kuwaiti Encyclopedia of Fiqh reads: “As for delaying the prayer until the end of its due time, it is contrary to what is best…. It is disliked to delay the prayer until the time of dislike.”
When one performs the Thuhr prayer at the end of its specified time just before the time for ‘Asr starts, he bears no sin for that because he has performed it within the specified legitimate time frame. However, he misses the reward for hastening to perform the prayer at the beginning of its due time unless he delays the Thuhr prayer because of intense heat, as this is admissible in the Sunnah.
It is also permissible to delay the Maghrib prayer until the end of its due time just before ‘Ishaa’ prayer is due; however, it is better to perform it at the beginning of its specified time. Many scholars held that Maghrib prayer has no time of necessity (i.e. the time to which it is not permitted for a person to delay his prayer unless he has a valid excuse). Al-Mardaawi 
a said about Fajr: “The correct view of the School is that no time of necessity is associated with it, but rather a time of virtue (i.e. at the beginning of its specified time) and permissibility (i.e. before the end of its specified time) as with Maghrib and Thuhr.” [Al-Insaaf]
It is impermissible to delay the ‘Asr prayer until the sun starts to turn yellow without a valid excuse, according to many jurists because it is considered a time of necessity. The commentary of Al-‘Adawi reads, “The time of necessity for ‘Asr begins after the sun turns yellow and lasts until sunset.”
The Hanbali scholar Al-Mardaawi said: “It is not permissible to delay the prayer, or a part of it, until the time of necessity, if there is no excuse according to the correct view of the School.” [Al-Insaaf]
For more benefit, please refer to Fataawa 88333 and 84538.
Allaah Knows best.