Receiving an unexpected large deposit in your bank account can initially seem like a windfall, but it can lead to significant tax complications if not handled properly. Tax expert CA Chandni Anandan emphasizes the importance of taking immediate action. If you notice an erroneous credit, refrain from using the funds and promptly inform your bank and the remitter. It is crucial to document all communications, including emails, as these serve as proof of your attempt to rectify the situation. According to the Income Tax Act, 1961, such funds may be classified as unexplained income if not reported, leading to severe tax implications. Specifically, unexplained income can be taxed at 60% under Section 115BBE, along with potential penalties. Anandan advises that proactive disclosure to your tax advisor is essential to prevent the funds from being categorized as income. By acting quickly and maintaining transparency, you can safeguard yourself against unnecessary tax liabilities.