After completing B.Sc. in mathematics there are two options to pursue a career. Either opt for higher studies or get a job in public or private sector. The major career options after the course are in the field of accountancy, business, computer programming etc. Some of the major career options are:

Mathematician

Actuary

Statistician

Accountant

Economist

If you want more opportunities with good package then I would suggest you for higher studies like M.Sc in Mathematics.

Good Luck!