Is rent received from a bank halaal?

Firstly: 

Dealing in riba is haraam and is a major sin. Allaah says (interpretation of the meaning): 

“O you who believe! Fear Allaah and give up what remains (due to you) from Ribaa (from now onward) if you are (really) believers.

279. And if you do not do it, then take a notice of war from Allaah and His Messenger but if you repent, you shall have your capital sums. Deal not unjustly (by asking more than your capital sums), and you shall not be dealt with unjustly (by receiving less than your capital sums)” [al-Baqarah 2:278-278]

Secondly: 

Once it is established that it is haraam to deal in riba, then it is also haraam to help others in that in any way whatsoever. That is because Allaah says (interpretation of the meaning): 

“Help you one another in Al‑Birr and At‑Taqwa (virtue, righteousness and piety); but do not help one another in sin and transgression” [al-Maa’idah 5:2]

Based on this, it is not permissible for you to rent a place to a bank that deals in riba, because that is helping the bank in this major sin, namely riba. It was proven that the Prophet (peace and blessings of Allaah be upon him) cursed the one who consumes riba, the one who pays it, the one who writes it down and the two who witness it, and he said: “They are all the same.” Narrated by Muslim, 1598. 

Al-Nawawi said: This indicates that it is haraam to cooperate in falsehood. 

Al-Sindi said: All of them are cursed for their participation in sin. 

The scholars of the Standing Committee for Issuing Fatwas were asked: 

I own a building and one of the banks applied to rent it. This bank is one of those that deal in riba. Is it permissible for me to rent it to this bank and others that deal in riba, or not? 

They replied: 

That is not permissible, because the bank mentioned is going to use it as a place for dealing in riba, which is haraam. Renting it to them for this purpose is helping them in doing something haraam. Allaah says (interpretation of the meaning): 

“Help you one another in Al‑Birr and At‑Taqwa (virtue, righteousness and piety); but do not help one another in sin and transgression” [al-Maa’idah 5:2]

Fataawa Islamiyyah, 2/423, 424 

Shaykh ‘Abd al-‘Azeez ibn Baaz said: 

There are many verses and ahaadeeth which indicate that it is haraam to cooperate in sin. By the same token it is haraam to rent property to owners of banks that deal in riba, because of the evidence mentioned. Fataawa Islamiyyah, 2/395 

The rent that you take from the bank is haraam wealth, which you must get rid of by giving it in charity. You must hasten to do that, because the Prophet (peace and blessings of Allaah be upon him) said: “Every body that is nourished on haraam things, the Fire is more fitting for it.” Narrated by al-Tabaraani; classed as saheeh by al-Albaani in Saheeh al-Jaami’, 4519. 

With regard to the rent that you took before you knew that it is haraam, it is permissible for you, because Allaah said, when He revealed the prohibition of riba (interpretation of the meaning): 

“So whosoever receives an admonition from his Lord and stops eating Ribaa, shall not be punished for the past; his case is for Allaah (to judge)” [al-Baqarah 2:275]

See also questions no. 2492 and 8196 

And Allaah knows best.