Introduction There is increasing recognition of the importance of clients of FSW as bridge group to HIV transmission. However, there is paucity of evidence that establishes the HIV vulnerabilities or risk among clients in India. The current analysis examines the changes in risk behaviors (condom use), prevalence of HIV and STIs, and the factors associated with condom use behaviors among clients of sex workers in three Indian states using data from a large scale cross-sectional bio-behavioural survey. Methods Data were derived from two rounds of integrated behavioural and biological assessments (IBBA) conducted among clients in the years 2006 and 2009 in Andhra Pradesh, Tamil Nadu and Maharashtra, India. Eligible clients for the survey included men aged 18 years or older who had bought sex from a FSW at least once in the previous month.Two stage probability sampling was used and time location clusters sampling was applied. Consented participants completed structured interviews to collect behavioural data and provided blood and urine samples for HIV, Neisseria gonorrhea, Chlamydia trachomatis, and syphilis testing. Results Samples of 4,821 and 4,803 clients were covered in IBBA rounds 1 and 2, respectively. The majority of the clients were literate, ever married and worked as a laborer in two consecutive rounds. Over three fourth of clients had first paid sex before age 25 years. Clients of FSWs had a higher level of condom use during last sex act (AOR-2.5, 95% CI 1.9-3.3) and consistent condom use (AOR-3.1, 95% CI-2.1-3.9) with occasional FSWs during Round 2, compared with Round 1. Clients 24 years or younger (AOR=4.2; 95% CI: 2.9-6.2) were most likely to have reported consistent condom use with FSWs when compared with clients 40 years or older. Clients who reported having sex with other men, were less likely to report consistent condom use (AOR=0.63; 95% CI: 0.4-0.8) with FSWs. Clients who had exposure to messages on STIs or condom use through media advertising were significantly more likely to report consistent condom use with FSWs (AOR=1.6; 95% CI: 1.1-2.3). Logistic regression analysis of factors associated with having an STI indicates that clients having sex with another man have significantly higher likely hood of having an STI (9.1% versus 6.6%; AOR=1.8; 95% CI: 1.1-2.9). Conclusion The findings strongly suggest improvements in condom use among the bridge population, which is also confirmed by the non-increase in HIV and STI prevalence. Exposure to media messages on STIs and condom have shown to positively influence condom use. These findings have programmatic implications, in that it increases understanding about the sub-populations