Urban sense of community and sense of place are dependent on streetscapes that foster the activity of walking. In this context, a key question is in which ways socio-demographic factors affect how individuals subjectively perceive the walkability of streets. This study addresses this question based on an online survey in which 1440 individuals of different gender, ages, sexual orientations, and immigration backgrounds provided more than 86,000 subjective assessments of street view images from 495 streets in Central London, UK. Statistically significant differences in the average and variance of assessments for most socio-demographic groups comparisons were found. This evidence suggests that theories relating the visually perceived features of the streets to their subjective walkability perception need to account for the influence of the individuals' socio-demographic factors.