Volunteer community health workers (CHWs) are one approach to addressing the health workforce crisis in developing countries. BRAC, a large Bangladeshi NGO, a pioneer in this area, uses female volunteer CHWs as core workers in its health programs. After 25 years of implementing the CHW model in rural areas, BRAC has begun using female CHWs in urban slums through its community-based mother, newborn and child health interventions. However, the program experienced suboptimal performance among CHWs, with a high percentage of them remaining in their positions but becoming "inactive", not truly participating in daily community health activities. This suggests a need to better understand the relative importance of factors affecting their active participation and to recommend strategies for improving their participation. This mixed-method study included a descriptive correlational design to assess factors relating to level of activity of CHWs and focus group discussions to explore solutions to these problems. A sample of 542 current female CHWs from project areas participated in the survey. Financial incentives were the main factor linked to the activity of CHWs. CHWs who thought that running their families would be difficult without CHW income had more than three times greater odds to become active. In addition, social prestige and positive community feedback to the CHWs were important non-financial factors associated with level of activity. In order to improve volunteer CHWs' performance, a combination of financial and non-financial incentives should be used.