Please don't be annoyed if you feel this is blatant advertising but I just wanted to give you an idea of why premiums differ.
For sole traders, partnerships or sole director Ltd companies you only need Public Liability Insurance (and Products Liability if you supply or wholesale goods). The premiums for such policies are usually standardised by an insurer, so they will have a fixed price for £1m, £2m etc. Treatment Risks isnt a cover you can buy on its own. Your Public Liability policy either covers treatment risks or doesnt and most don't.
Once you employ staff or use sub contractors (labour only) you legally need Employers Liability Insurance. Some insurers then charge based on a rate per person which can be expensive and time consuming, having to remember to ring your broker when people start or leave. Some, like the insurer we use provide rates based on turnover and wages. The higher these figures, the higher the premium. And the reason for this is the higher the turnover the higher the risk of a Public Liability claim occuring as there is more work being done. The higher the wages, the higher the risk of an Employers Liability claim occuring as there are more employees.
If anyone needs any advice or a quote give us a shout.