I am repeating the same question that I have asked before. You instructed me to refer to similar fatwas, but I did not get my answer in full by referring to the fatwas that you asked me to see. So please answer this question for me: In Bangladesh, if one invests money in a national savings scheme, they can enjoy an income tax rebate of 15,000 taka per 100,000 taka invested. Does this not constitute interest? Taka is the currency of Bangladesh.

All perfect praise be to Allaah, The Lord of the Worlds. I testify that there is none worthy of worship except Allaah and that Muhammad, sallallaahu ʻalayhi wa sallam, is His slave and Messenger. 

Based on the information that we have found about the mentioned savings scheme, it is based on interest. Hence, it is impermissible to partake in this scheme at all regardless of whether you would be exempted from some taxes or not. We have detailed the religious ruling on engaging in national interest-based transactions and loans so as to benefit of tax rebates in fataawa 90774 and 90819.

Hence, it is prohibited to invest in such savings scheme because it is forbidden interest.

Allaah knows best.