This paper shares with the research community how to achieve, effectively and easily, lateral submicron separations in the standard 2 lm PolyMUMPS process without any fabrication intervention or post-processing, based on the oxide sidewall spacer technique. Thousands of nanoseparations were created and successfully tested by visual inspection and by a simple capacitance measurement. The lateral separations attained were less than 440 nm and reached as low as 280 nm. To corroborate the findings, measurements were performed on different capacitors fabricated in different fabrication runs with consistent results. This is the first time that submicron lateral distances are reported in PolyMUMPS using the oxide spacer technique.