I have natural gas for heat and I heat a 2,000 square foot well insulated home with a natural gas high efficiency furnace and it costs me $250.00 to $300.00 per month.
The $250.00 per month is November to December and then January and February the furnace runs more because of the colder weather which jumps the natural gas heating bill up to $300.00 per month.
That's still cheaper than it would cost me to heat with heating oil, electricity or even firewood.