Answered by Shaykh Yūsuf Badāt
Is the walīmah valid if husband and wife have not consummated their marriage by then?
Jazāk Allāh Khayr/ Thank you for your question.
The walīmah banquet is a sunnah (prophetic practice).
This gathering can take place any time soon after the nikāḥ (Islamic marriage). Even though it is preferred to hold the walīmah after consummation of marriage, it is not mandatory to do so. (See: Awjaz al Masālik, I’elā al Sunan and Tuḥfat al Muḥtāj)
Anas (may Allāh be please with him) said,
“The Prophet (peace and blessings upon him) consummated his marriage to Ṣafiyyah (may Allāh be pleased with her), after which I [upon the instruction of the Prophet] invited the Muslims present to a walīmah meal” (Ṣaḥīḥ Bukhārī)
It is also worthy to note that in Islam, consummation of marriage occurs when the couple spend some time after the marriage in seclusion. Intercourse is not necessary for consummation of marriage [in Islamic law]. (See Fiqh al Islāmīy wa Adillatuhū and other famous manuals of fiqh)
And Allāh Knows Best