A BPP measures fetal well-being, while the ultrasound provides information about anatomic structures. So as long as both services are ordered and medically necessary, you can bill for both. In fact, CPT details exactly what the ultrasound codes include. Code 76805 represents "determination of number of fetuses and amniotic/chorionic sacs, measurements appropriate for gestational age (> or = 14 weeks 0 days), survey of intracranial/spinal/abdominal anatomy, 4-chambered heart, umbilical cord insertion site, placenta location and amniotic fluid assessment and, when visible, examination of maternal adnexa."
On the other hand, 76811 includes everything in 76805, "plus detailed anatomic evaluation of the fetal brain/ventricles, face, heart/outflow tracts and chest anatomy, abdominal organ-specific anatomy, number/length/architecture of limbs and detailed evaluation of the umbilical cord and placenta and other fetal anatomy as clinically indicated," according to CPT.