Inevitably I'll have to show my new employer my p45, butI feel really uncomfortable them knowing how much I earned in my previous job. Any advice? Thanks.
If you don't have a P45 your new employer will give you a form P46 (it doesn't show previous pay) to complete. Once processed by the tax office they will send your employer your new tax code. Until received you will be taxed at basic rate.
Not every new employee brings in a P45.
is this basic rate called "emergency tax"? Does this mean that your employer wont know where you last worked or how much you earned or when you last worked if you so wish to keep it secret?