Summary. In pregnancies at risk of haemophilia, foetal sex determination is used to plan perinatal management and to guide the offer of invasive testing in pregnancies with a male foetus. Traditionally ultrasound from 12 weeks gestation has been used, but recently options for early foetal sex determination have increased following the introduction of non-invasive prenatal diagnosis (NIPD) using cell free foetal DNA in maternal plasma. This study was conducted to identify clinical practices and examine health professional attitudes regarding NIPD for foetal sex determination. A qualitative approach using one-to-one semi structured interviews was used to enable an in-depth exploration of current practice, introduction and use of NIPD and benefits and disadvantages of offering NIPD. Interviews were conducted with consultant haematologists (N = 7), specialist haemophilia nurses (N = 7), genetic counsellors (N = 6), consultants in clinical genetics (N = 5), specialist midwives (N = 2) and obstetricians (N = 5) from 24 services across the United Kingdom (UK). Key differences in how NIPD for foetal sexing is utilized throughout the UK were identified. Some services routinely offered NIPD to all carriers of haemophilia or to all carriers of severe haemophilia, others discussed the value of NIPD with all or primarily offered NIPD as a first step to invasive testing. This study informs our understanding of how NIPD is being utilized and provides unique insights into current practice. The identification of variation between services in how prenatal testing options are offered has implications for future policy and guidelines for prenatal care.