The present study aims to study the indoor and outdoor air quality in an urban center and its immediate rural areas. The measurements of particulate matter (PM10 and PM2.5) and the Air Quality Index (AQI) during cooking hours in the morning, daytime, and evening, using a real-time portable air sampler were performed as a part of the study. Five residential colonies in urban and rural localities of a North Indian city Lucknow, covering a total of sixty households (HHs), were selected for detailed sampling over a period of two months (February and March 2018). A major difference in the cooking pattern was observed in urban and rural localities in terms of the use of cooking fuels. The average indoor PM2.5 concentrations in urban and rural HHs were 115.4 mu g/m(3) and 337.2 mu g/m(3), respectively. These values were 1.3 and 7.8 times higher than the outdoor PM2.5 concentration levels. Similarly, the average indoor PM10 concentrations in urban and rural HHs were 178.3 mu g/m(3) and 362.4 mu g/m(3), respectively. These values were 1.2 and 4.8 times higher than the outdoor levels. The average AQI be the highest (368.8) for rural indoors, primarily due to biomass burning, and the lowest (84.9) for rural outdoors during the sampling period. A majority (> 70%) of the rural HHs, with women being the most susceptible groups for the exposure, reported ailments like prolonged coughing and eye irritation during cooking hours, while urban HHs were relatively better off. The difference in the indoor and outdoor urban and rural air quality was observed to be the least during the daytime and evening, indicating the variations in emission patterns during the cooking hours. It is expected that the outcome of this study will help in taking progressive measures to reduce the emission of particulate matter while cooking, especially in vulnerable rural households.