Generalised trust has been associated with a range of positive effects. However, the problem is that little is known about the spatial distribution of trust at a small area level due to the lack of geographically detailed data. Censuses do not provide data on social capital, attitudes, and values, and other social surveys commonly lack spatial detail. This paper examines the intraurban geography of generalised trust based on small area estimates derived from synthetic spatial microdata created for Sydney, Australia. The synthetic data were generated using combinatorial optimisation and data from the Household, Income and Labour Dynamics in Australia (HILDA) survey and the 2006 Census. Based on these data, a clear spatial pattern of generalised trust in Sydney can be identified independent of administrative data such as local government areas. The socioeconomic status and ethnic composition in neighbourhoods relate in large parts- though not fully-to the geographical pattern of trust. Variations from the pattern tend to be associated with specific local characteristics. The analysis further suggests that associations between generalised trust and other variables such as population density, residential mobility, and housing situation are not consistent across the city. In addition, mapping the small area estimates shows that small pockets of neighbourhoods with low and high levels of trust exist within larger areas characterised by opposing levels of trust, and often have neighbouring transition areas with medium levels of trust.