This paper analyses which sources of low-carbon hydrogen for the Northwest European market are most competitive, taking into account costs of local production, conversion and transport. Production costs of electrolysis are strongly affected by local renewable electricity costs and capacity factors. Transport costs are the lowest by pipelines for distances under 10,000 km, with costs linearly increasing with distance. For larger distances, transport as ammonia is more efficient, with less relation to distance, despite higher conversion costs. The most competitive low-carbon hydrogen supply to the Northwest European market appears to be local Steam Methane Reforming with Carbon Capture and Storage when international gas prices return back to historical levels. When gas prices, however, remain high, then import from Morocco with electrolysis directly connected to offshore wind generation is found to be the most competitive source of low-carbon hydrogen. These conclusions are robust for various assumptions on costs and capacity factors.