I'm just curious as to the average Cost to heat the Home with an Oil Furnace? Understandably were experiencing the New Politically Correct term Polar Vortex.. Our home is your typical matchbox style, no wasted spaces.. Originally 3 BDR, a Finished Basement.. Oil Heat and the House holds it's Heat Superbly... It's just the Wife and I, we find it Comfortable keeping the Heat at 18C', were accustomed to throwing a sweater on.. lol... We just had the Furnace Tank topped up, yes I realize we're talking in Baseball Terms if you will.. It was 60 days pervious since the last Top Up.. Today's fill up was 485.40 Litres, costing $1.18900 a litre.. Thanks

Too many variables. Size, exposure, insulation, window condition, wind screening, ambient temperature etc.

Polar vortex is a very old term. Nothing PC about it.
Call your oil supplier. They track 'degree days' for your area and can tell you what others are like. Keeping your house at 18C (64.4F) is below the norm. I keep mine at 67 days and 60 nights. I use propane. My supplier was shocked at how little I am using compared to the last owner of my house.

If I computed gallons from liters correctly, your price per gallon is about $ 4.57. That is about $ 0.92 more than the average price I could find in my area of central PA.
We use propane and received a letter from the supplier saying that his suppliers are not honoring their contracts because of tremendous demands and emergency distributions of fuel.
We use our basement to the fullest extent and use portable 220 V electric heaters to heat only the areas of the house that we are occupying at any given time.
Our last electric bill was $ 141 and that billing period included at least 20 days of these extremely cold periods.
We received about $ 450 worth of propane which was the first delivery since April '13, which was about the same time we replaced our propane water heater with an electric water heater and timer. We would have had at least one other delivery between April '13 and Jan '14 if we still had the propane water heater which was providing 120 degree water 24 hours per day, and I had no way to use the timer that I know of. The heater failed and gave me a good opportunity to convert to electric.
So, the only reference I can provide is that we used $ 450 of propane between April 13 and mid jan. 2014.
Fuel dealers use degree days to determine when to fill up tanks. They can give you a comparison if they will, but mao is correct- many, many variables.