Can a set of low-cost behavioural nudges encourage more small businesses to adopt productivity-raising digital technologies? This randomised controlled trial sought to test whether businesses could be nudged into using a cloud-based system to improve the efficiency of invoice processing. All participants in the trial were offered access to the system free of charge for a 12-month period, with a treatment group receiving weekly email reminders to make use of the system. In the event, few businesses made significant use of the new technology, with no detectable differences between the treatment and control groups. The lack of adoption appears to be due to a combination of lack of need among those that signed up, delays in launching the platform, and the incorporation of similar functionality into leading accountancy software packages during the period when the trial was being carried out. Potential users were able to judge whether the product met their needs at the point of registration, so there was little potential for the treatment to have an impact on this decision. This study highlights the difficulty of conducting research in a rapidly-changing competitive environment.