The pilgrim doing qiraan only has to do saa’i once
Question

A question about pilgrimage to the sacred House of Allaah. With regard to qiraan Hajj, can we enter ihraam for Hajj and ‘Umrah together, on the basis that the saa’i done between al-Safa and al-Marwah (after the tawaaf of arrival) is the saa’i which we intended to do after tawaaf al-ifaadah? I.e., that we do not have to do saa’i after tawaaf al-ifaadah so long as we did saa’i after the tawaaf of arrival?.
Praise be to Allah.The pilgrim doing qiraan is the one who enters ihraam for ‘Umrah and Hajj together. It is better to do saa’i after the tawaaf of arrival, as the Prophet (peace and blessings of Allaah be upon him) did, but he may delay it and do it with tawaaf al-ifaadah. 
There is evidence that the pilgrim doing qiraan only has to do one saa’i, for example: 
1 – The Prophet (peace and blessings of Allaah be upon him) did qiraan, and he only did one saa’i between al-Safa and al-Marwah, after the tawaaf of arrival. 
Muslim (1215) narrated that Jaabir ibn ‘Abd-Allaah (may Allaah be pleased with him) said: “The Prophet (peace and blessings of Allaah be upon him) and his companions only did saa’i once between al-Safa and al-Marwah, after the first tawaaf. 
Al-Nawawi (may Allaah have mercy on him) said: 
“The Prophet (peace and blessings of Allaah be upon him) and his companions only did saa’i once” means that the Prophet (peace and blessings of Allaah be upon him) and those of his companions who were with him did qiraan, which means doing saa’i between al-Safa and al-Marwah once.  Those of his companions who were doing tamattu’ did saa’i twice, once for ‘Umrah and then again for Hajj on the Day of Sacrifice. This hadeeth is clear support for al-Shaafa’i and those who agreed with him that the pilgrim doing qiraan only has to do one tawaaf, i.e., tawaaf al-ifaadah, and one saa’i. 
2 – al-Bukhaari (1556) and Muslim (1211) narrated that ‘Aa’ishah (may Allaah be pleased with her) said: Those who had entered ihraam for ‘Umrah (i.e., those who were doing tamattu’) circumambulated the House and did saa’i between al-Safa and al-Marwah, then they exited ihraam, then they did another tawaaf after they came back from Mina. But those who were combining Hajj and ‘Umrah (i.e., those who were doing qiraan) did only one saa’i. 
Shaykh Ibn ‘Uthaymeen was asked: is one tawaaf and one saa’i sufficient for the pilgrim doing qiraan?  
He replied: 
If a person does qiraan Hajj, then the tawaaf of Hajj and the saa’i of Hajj are sufficient for both Hajj and ‘Umrah. The tawaaf of arrival (tawaaf al-qudoom) is Sunnah, and if he wants he may do saa’i after the tawaaf of arrival as the Prophet (peace and blessings of Allaah be upon him) did, or if he wants he may delay it until the day of Eid, after tawaaf al-ifaadah. But it is better to do it sooner because that is what the Prophet (peace and blessings of Allaah be upon him) did. When the day of Eid comes, he should do tawaaf al-ifaadah only, and not saa’i, because he has already done saa’i. The evidence that one tawaaf and one saa’i is sufficient for both Hajj and ‘Umrah is the words of the Messenger of Allaah (peace and blessings of Allaah be upon him) to ‘Aa’ishah (may Allaah be pleased with her) when she was doing qiraan Hajj: “Your tawaaf around the House and (your saa’i) between al-Safa and al-Marwah is enough for your Hajj and ‘Umrah.” Narrated by Abu Dawood, 1897’ classed as saheeh by al-Albaani in al-Silsilah al-Saheehah, 1984. Thus the Prophet (peace and blessings of Allaah be upon him) explained that one tawaaf and one saa’i in the case of qiraan is sufficient for both Hajj and ‘Umrah. Fataawa Arkaan al-Islam, p. 563. 
And Allaah knows best.