Oil & gas is considered the largest industry in terms of dollar value, generating hundreds of billion dollars globally. Oil & gas contributes a sizable percentage of the GDP of the producing countries. It has three key sectors, namely: upstream, midstream, and downstream. The upstream is the exploration of oil & gas fields and drilling of exploration wells; midstream is the transportation, storage, and processing of oil & gas; downstream is the filtering of the raw materials obtained during the upstream phase. Finished products are in the form of diesel, petrol, gasoline, lubricants, kerosene, liquified petroleum gas, etc. Presented here are the financial model templates related to oil & gas.