is it cheaper to run a little fan heater in a room for a while than to have the radiators on?

iv not put the radiators on the timer yet to come on in the morning and late afternoons etc..
just wondering if it might just be cheaper to heat a room up with those little fan heaters,does anyone know if it will be cheaper? the cost of my gas bill last year was just ridiculous.

Fan heaters eat electricity for a past time. Expensive to run. I would use the C/H Mine comes on at 06.00 am and off at 10.00 and on at 04.00am and off at 10.00 am and if it is really cold i use the over ride button. Set the room thermostat at 18c