The hydrocarbon group-type composition of fossil fuels affects their performance and environmental properties. Normal phase high performance liquid chromatography (NPLC) is commonly used to determine the proportion of saturates, mono-, di-, tri-, and polyaromatics in fuel and gas oil samples. It is often difficult to achieve sufficient resolution between group-types using conventional normal phase columns and conditions. This incomplete resolution can negatively impact the accuracy of the group-type analysis. This paper investigates the use of titania, zirconia, carbon, silica, and aminopropyl bonded silica columns to improve group-type resolution using high temperature NPLC. Better group-type selectivity and faster separations were obtained by increasing column temperatures from 35 to 200 degrees C. A high resolution hydrocarbon group-type analysis method was developed using titania and silica columns with valve-switching and dual gradients to analyze three heavy gas oils (boiling range > 350 degrees C). A titania column at a high flow rate of 5.0 mL min(-1) yielded separations in only 3 min.