Up to 96.7 percent efficient home furnaces

A high-efficiency furnace (90% plus) furnace should save you between 20 and 25 percent on your home heating bill

The best choice is to choose a furnace with an AFUE rating of over 90 percent. These “condensing furnaces” recover extra heat by extracting water from the combustion gases within a special corrosion-resistant heat exchanger.

The Energy star site has information on more efficient gas and oil furnaces.

Here is a pdf list of efficient gas furnaces. Many are in the 95-96.7% efficiency range.

The first step is a home energy audit.

Getting a more efficient furnace should be done in combination with improving the sealing of ducts (20% of heat can be lost) and improved home insulation.

An assessment of home energy efficiency should be performed.