The development of micromachining has enabled the production and improvement of components and features on microscale, which are essential in many industries. However, as the scale decreases, phenomena such as ploughing and tool run-out significantly impact product quality, making it crucial to carry out studies to understand the cutting mechanisms on a microscale, which change depending on the characteristics of the process performed. Therefore, the objective of this study is to evaluate how the feed per tooth affects the quality of the machined surface in the micromilling process of AISI 316L austenitic stainless steel. For this purpose, 0.4 mm diameter micromills were used to manufacture microchannels using feed rate of 0.5, 1 and 5 µm/tooth. The machined surfaces of each microchannel were observed using a scanning electron microscope, and their surface roughness was measured. These analyses were conducted to assess the characteristics of the machined surface on each microchannel. According to the experimental results obtained for micromilling AISI 316L with the selected cutting parameters, the average surface roughness (Ra) showed no statistically significant difference between feeds of 0.5 µm/tooth and 1 µm/tooth, both yielding an Ra of approximately 0.04 µm. However, when the feed rate was increased from 1 to 5 µm/tooth, the surface roughness also increased, with the average surface roughness (Ra) rising from 0.04 to 0.15 µm. In the experiments performed, the influence of the scale effect on the surface finish was not observed, as the selected feed per tooth values are higher than the estimated minimum chip thickness (0.27–0.37 µm). Analysis of the micromachined surface images showed that lower feed rates result in a better surface finish, while higher feed rate led to material detachment, particle adhesion, and the formation of internal burrs due to side flow.