The offshore wind farm (OWF) industry is of growing importance, particularly in Europe. However, the local socio-economic impacts of OWF projects have received little attention compared with biophysical impacts. Yet, they have the potential to be significant for the regeneration of declining coastal communities. Drawing on findings from academic and industry literature, from a review of ESs (Environmental Statements) for OWFs and from particular case studies, it highlights some of the differential coverage of social and economic impacts, and the differences between predicted and actual impacts, by stage in project life. For example, the ES predictions substantially overestimate local offshore construction stage economic impacts, but underestimate other elements of the OWF lifecycle, including onshore construction, and especially the 20–25 years of the operation and management stage. The Aberdeen (Scotland) case study shows the importance of the engagement strategy of the developer. The case study of the major Hornsea projects, off the coast of Yorkshire (England), also highlights the positive and cumulative impacts of scale and hub status, where a programme of large OWFs can have important local impacts. The research identifies some factors leading to the identified outcomes, including the changing size and location of OWF projects, the relevant legislative and regulatory context behind the decision-making processes for OWF projects, and the responses and relationships of stakeholders involved in the process. The key role of monitoring impacts is an underpinning issue and a requirement for the more effective assessment of impacts.