ESM0539 - Guide to determining status: engaging helpers
A worker who hires an assistant is unlikely to be an employee. That is especially so where the nature of the work actually requires an assistant (for example, where installing or moving heavy objects is involved) and the worker is required to hire help at his or her own expense. On the other hand, a dairy may turn a blind eye to a milk roundsman deciding to hire a child as an assistant during the school holidays to ‘lighten the load’. That would be rather different and would not inevitably mean that the milkman is self-employed.
Where a worker agrees to undertake a specific task it might make sense for the worker to hire an assistant if that is profitable and a claimed right in this regard may be perfectly in order. The same applies to pieceworkers. But you do need to be sure that the work and payment involved make the hiring of an assistant a viable proposition. Where the worker is hourly paid it is unlikely the worker would pay someone else for ‘help’ as such (the worker would still be working at the same remuneration but would effectively be voluntarily funding a helper out of their own pocket). And if the remuneration is low, is it possible to hire assistants? You should consider such claims critically.