It is Not Permissible For a Man to Have More Than Four Wives at the Same time

Question :

Is it permissible for a man to have more than four wives or not? And what is the evidence?

Answer:

It is not permissible for a man to have more than four wives, according to the Words of Allah, Most High:
"And if you fear that you shall not be able to deal justly with the orphan girls then marry (other) women of your choice, two or three, or four; but if you fear that you shall not be able to deal justly (with them), then only one or (slaves) that your right hands possess."

And in the language of the Arabs this is the same as their saying:
March two, three or four, meaning march in rows, there being in each row two, three or four. It does not mean in the language of the Arabs, nor in common usage, that nine of them should combine in one row when they march. Therefore, the meaning of the Verse is: If you fear that you will be unjust if you married the orphan girls, then turn away from them in favor of marrying others; and whoever among you desires to marry a number of women should marry two, three, or four. Since the limit has been designated in a situation where one is blessed with plurality, and we are encouraged to turn away from marrying orphan girls in favor of other women (up to) four wives, it proves that it is not permissible to combine more than that.

In the Hadith, it is reported that Qais bin Al-Harith, may Allah be pleased with him, embraced Islam and he had eight wives, so the Prophet ordered him to choose four of them and to part from the others. Narrated by Abu Dawud and Ibn Majah.

Source:
The Permanent Committee
Fatawa Islamiyah, Vol. 5 Page 357