Slim hole drilling has gained wide acceptance, however, it presents a new set of challenges and problems. One such challenge is reducing annular pressure losses (APLs). Due to the reduced annular clearance in slim hole wells, the APL is usually high, translating to a high equivalent circulating density which can lead to fracturing the formation and lost circulation. Fifty-three fluids were evaluated for their APLs using three different wellbore configurations under atmospheric conditions and at 150 degrees F. Each fluid was characterized using the Bingham Plastic and Power Law rheological modes. It was observed that the partially hydrolyzed polyacrylamide (PHPA) viscosified brines gave the lowest frictional pressure losses of all fluids tested. However, the xanthan viscosified brines exhibited better carrying capacity due to their high viscosities. As expected, APL gradients were reduced at high temperatures due to reduced viscosities which led to reduce carrying capacities of the fluids.