An ultrasound flow meter unit arranged to measure a fluid flow rate with one or more ultrasound transducers (606), and a circuit board (602) with an electronic circuit arranged to operate the ultrasound transducer(s) (106, 306). The ultrasound transducer (606), e.g. in the form of a piezo-electric element, is mechanically fixed to the circuit board (602) by a first electrically conducting fixing means which additionally serve(s) to provide an electrical connection between an electrical terminal of the transducer (606) and the electronic circuit. Hereby a functional flow measurement unit (600) is provided which can be tested prior to assembly with a flow meter housing etc. Preferably, a set of ultrasound transducers (106, 306) are soldered directly onto electrically conducting paths (631) on a surface of the circuit board (602) being in electrical connection with the electronic circuit, e.g. in a single SMT mounting process together with mounting of all other electronic components on the circuit board (602). Through-going openings (630, 640) of the circuit board (602) in the vicinity of these conducting paths (631) serve to provide thermal elasticity. A metal clip soldered to the circuit board (602) may serve to electrically connect a second electrical terminal of the transducer (606) to the electronic circuit.