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One of the biggest drilling challenges in low-temperature environments such as in the Arctic region is maintaining fluid properties under an extreme temperature difference between the high-temperature bottom hole and the low-temperature surface. The rapid change in temperature conditions can affect mud rheological properties and reduce drilling performance. The heat released from the mud circulation system can also cause thawing of the permafrost and gas hydrate-bearing formations impacting the wellbore integrity and releasing greenhouse gases to the environment. Creating a more thermally independent drilling mud becomes one of the solutions to reduce the potential problem that may arise. However, the already available thermally stable muds used in the oil industry are mostly formulated in the nonaqueous-based system. On that basis, this research aimed to design a drilling mud formulation in the aqueous-based system as an alternative solution to reduce the environmental cost due to the use of nonaqueous-based muds in the Arctic and deep-water drilling operations. Silica (SiO2) and alumina (Al2O3) nanoparticles were added to the freshwater and saltwater-based formulations designed to provide a drilling mud with a more temperature-independent behaviour. A series of experimental investigations were conducted as a screening method to select one nano-based mud formulation that would provide the most optimum performances in rheological properties, filtration properties, fluid dynamics, and heat transfers. The rheological properties investigation was conducted using a direct-reading viscometer at a temperature range 0-80°C. The filtration properties investigation was conducted using a static filter press under a 700 kPa differential pressure. A flow loop experimental set-up was designed and fabricated to appraise flow and heat transfer performances by circulating the preheated mud samples at different flow rates through a coiled tube section immersed in a cooling tank. evaluating laminar pressure loss and Nusselt numbers which reflects the extent of convective heat transfers. The results concluded that a saltwater-based mud with 0.1 wt% silica nanoparticles exhibited improved thermal stability indicated from the smaller variations in rheological properties across the temperature range. This mud formulation also exhibited the lowest filtrate volume with up to 11% reduction from the base sample. The mud sample also showed a reduction in pressure loss for about 4.9% as observed at Re = 800 and a 3.6% reduction in Nusselt number as observed at Re = 600.