This depends on the type of pension and on the scheme rules. If you have a 'money purchase' pension, it's likely that the value of your fund will be paid out to a dependant. You should check your own scheme documents to find out who decides who the money gets paid to – you may need to fill in a nomination form.
If you were in a salary-related scheme, a pension should be payable to your spouse or civil partner. It's likely to be based on your deferred pension, but the amount will depend on the scheme rules, and may be a smaller proportion than if you had died in service. The rules may also provide for a lump sum to be paid, but this may be just a refund of your contributions. You should ask your scheme administrator for more information.