I have a small saving in a Bank Account for which I have recieved interest. I am in the process of clearing it up now. However, I also had previously invested in a few Banking stocks (unaware that it was wrong), which have depreciated in value. can I set off my loss in the banking stocks with the interest on my savings account??.


Praise be to Allaah.
 

The one who has repented from riba should not take anything
but the capital of his wealth only, because Allaah says (interpretation of
the meaning): 

“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 2:279] 

It is not permissible to take anything more than that; if a
person has taken it he must get rid of it by spending it on charitable
causes. 

In the question there are two issues which have nothing to do
with one another, and we must deal with them separately: the interest which
has been taken, and offsetting the depreciation in the value of shares with
this interest.  

With regard to the first issue: putting money in a riba-based
bank and taking more money than the original capital. The scholars of the
Standing Committee said: 

The interest which the bank pays to depositors on the money
that they deposit is considered to be riba (usury, interest), and it is not
permissible to make use of this money. The person must repent to Allaah from
depositing money in riba-based banks, he should withdraw the money that he
deposited and the interest, then keep his original amount and spend the
interest in charitable causes, such as on the poor and needy, renovating
public facilities, and so on. 

Fataawa Islamiyyah, 2/404. 

Shaykh ‘Abd al-‘Azeez ibn Baz (may Allaah have mercy on him)
said: 

With regard to the interest that the bank gives you, do not
give it back to the bank and do not consume it, rather spend it on
charitable causes such as giving it to the poor, renovating public
washrooms, and helping debtors who are unable to pay off their debts. 

Fataawa Islamiyyah, 2/407 

With regard to the second issue: offsetting the depreciation
in the value of shares with this interest, it is not permissible to do this,
because it is not permissible for you to take this money and benefit from
it, as stated above. 

The person who buys shares has to bear losses in the value of
his shares from his own money; he does not have the right to offset those
losses with money that he acquires from haraam sources. 

The fact that he entered into this transaction when he was
unaware of the fact that it is haraam means that he is absolved of any sin;
he is excused by the fact that he did not know. But that is not a reason for
allowing him to benefit from the interest by using it to offset these
losses. 

And Allaah knows best.