Do We Pray Sunnah when Travelling?
Question

The traveller may offer whatever Sunnah prayers he wants. It is not Sunnah to omit any supererogatory prayers apart from the regular Sunnah prayers before and after Dhuhr and Sunnah prayers of Maghrib and `Isha.
Praise be to Allah.The traveller may offer whatever supererogatory prayers he wants. It is not Sunnah for him to omit any of the supererogatory prayers apart from the regular Sunnah prayers before and after Dhuhr and the regular Sunnah prayers of Maghrib and `Isha’. 
Apart from that, the traveller may offer any of the Sunnah prayers. Muslim (680) narrated from Abu Qatadah (may Allah be pleased with him) that the Prophet (peace and blessings of Allah be upon him) prayed the regular Sunnah prayer of Fajr when travelling . 
It was also proven that the Prophet (peace and blessings of Allah be upon him) prayed Duha with eight Rak`ahs in Makkah on the day when Allah enabled him to conquer Makkah. (Narrated by Al-Bukhari, 357 and Muslim, 336) 
And the Prophet (peace and blessings of Allah be upon him) prayed Witr when travelling . (Narrated by Al-Bukhari, 1000) 
Shaykh Ibn ‘Uthaymin (may Allah have mercy on him) said:  
“With regard to the regular Sunnah prayers , I have studied what was narrated in the Sunnah concerning the supererogatory prayers, and it seems to me that the regular Sunnah prayers of Dhuhr , Maghrib and `Isha’ need not be offered (by the traveller), but he may offer other supererogatory prayers apart from that, such as the Sunnah of Fajr, the Sunnah of Witr, Qiyam Al-layl, Duha and Tahiyyat Al-masjid (two Rak`ahs to greet the mosque), and supererogatory prayers in general.” (Majmu` Fatawa Ibn `Uthaymin, 15/258) 
Ibn `Umar (may Allah be pleased with him) criticised those who prayed regular Sunnah prayers when travelling. 
Al-Bukhari (1102) and Muslim (689) narrated that Hafs ibn `Asim ibn `Umar ibn Al-Khattab (may Allah have mercy on him) said: Ibn `Umar set out in the morning on the way to Makkah, and led us in praying Dhuhr, two Rak`ahs. Then he moved away and we moved away with him until he came to his mount. He sat down and we sat with him. Then he turned back and saw some people standing and said: “What are these people doing?” I said: “They are praying supererogatory.” He said: “If I had wanted to pray supererogatory, I would have offered the prayer in full. O son of my brother, I accompanied the Messenger of Allah (peace and blessings of Allah be upon him) on a journey and he did not do more than two Rak`ahs (when travelling) until Allah took him (in death). And I accompanied Abu Bakr and he did not do more than two Rak`ahs (when travelling) until Allah took him (in death). And I accompanied `Umar and he did not do more than two Rak`ahs (when travelling) until Allah took him (in death). Then I accompanied `Uthman and he did not do more than two Rak`ahs (when travelling) until Allah took him (in death). And Allah says (interpretation of the meaning):
‘Indeed in the Messenger of Allah (Muhammad) you have a good example to follow’ [Al-Ahzab 33:21].”.
And Allah knows best.