The German cockroach, Blattella germanica (L.), is a common pest found in apartment buildings. Prevalence of cockroach infestations is affected by both environmental conditions and building occupant behavior, but their relationships are not well studied. The objective of this study was to analyze the presence of German cockroaches in relation to environmental conditions, resident demographics, and residents' tolerance of cockroaches. We conducted resident interviews, placed sticky traps to detect the presence of German cockroaches, and assessed apartment conditions. A total of 388 apartments from seven low-income apartment buildings, occupied by senior citizens in New Jersey, United States, were included. Among the 344 apartments where trap count data were obtained, 30% had German cockroaches. Among interviewed residents whose apartments had existing cockroach infestations, 36% were unaware of the presence of cockroaches. The odds of having cockroaches in apartments with a 'poor' sanitation rating in kitchens and bathrooms was 2.7 times greater than that in apartments with better sanitation conditions. Residents' tolerance to cockroaches is significantly associated with presence of cockroaches and cockroach population size. The median cockroach count when residents were bothered by cockroaches was ≥3, based on deployment of 4 sticky traps per apartment, over a 2-wk period. Assessing and reducing cockroach tolerance thresholds and improving housekeeping through resident education and assistance from community and housing management should be incorporated in future cockroach management programs in order to reduce high cockroach infestation rates found in similar communities.