It is not permissible to use the interest money accumulated in your bank account, as this act is considered a major sin.
Allah says in Quran ( what could be translated as ):
“O you who believe! Be afraid of Allah and give up what remains (due to you) from Riba (from now onward) if you are (really) believers.
“And if you do not do it, then take a notice of war from Allah 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, 279]