Unintended pregnancy (mistimed or unwanted) remains an important health issue for women. The purpose of this study was to determine the prevalence of and factors associated with risk of unintended pregnancy in a sample of Victorian women attending family planning clinics. Methods. This cross-sectional survey of three Family Planning Victoria Clinics from April to July 2011 recruited women aged 16-50 years with a male sexual partner in the last 3 months, and not intending to conceive. The questionnaire asked about contraceptive behaviours and important factors that influence contraception use (identified from a systematic literature review). Univariate analysis was calculated for the variables of interest for associations with contraceptive use. An overall multivariate model for being at risk for unintended pregnancy (due to inconsistent or ineffective contraceptive use or non-use) was calculated through backward elimination with statistical significance set at 1 partner in the last 3 months (OR 3.2, 95 CI 2.3-4.6). These women were dissatisfied with current contraception (OR 2.5, 95 1.8-3.5); felt vulnerable to pregnancy (OR 2.1, 95 CI 1.6-3.0); were not confident in contraceptive knowledge (OR 2.6, 95 CI 1.5-4.8); were unable to stop to use contraception when aroused (OR 2.1, 95 CI 1.5-2.9) but were comfortable in speaking to a doctor about contraception (OR 2.3, 95 CI 1.1-4.1). Conclusion: Despite reported high contraceptive usage, nearly 40 of women were at risk for unintended pregnancy primarily due to inconsistent contraceptive use and use of ineffective contraception. Strategies for improving consistency of effective contraception use or greater emphasis on long-acting contraception may be needed for certain subpopulations at higher risk for unintended pregnancy.