My mother is a widow. She has some money invested in the fixed income. She want to spend partly on herself and other part on charity. Is it allowed?

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 is His slave and Messenger.

It is permissible in principle for a person to spend on himself from his money or monthly income provided he spends appropriately without being extravagant as Allaah Says (what means): {…and eat and drink, but be not excessive. Indeed, He likes not those who commit excess.}[Quran 7:31].

A person will also be rewarded for giving in charity if he does so for the sake of Allaah, provided he donates from lawfully earned money. Allaah Says (what means): {Do they not know that it is Allaah who accepts repentance from His servants and receives charities.}[Quran 9:104].

This means that Allaah accepts it and increases it for the one who donated it until it becomes like a huge mountain.

However, you did not clarify to us the kind of investment so that we would know whether it is from the kind on which Zakat must be paid on the capital money and the profits, or from the kind on which Zakat must be paid on the income only.

Finally, it should be noted that it is forbidden for a Muslim to invest his money in what is forbidden, like investing money in usurious banks.

For more benefit, please refer to Fatwa 84188. 

Allaah Knows best.