The financial and resource costs of hiring new members of staff.  A cost per hire  includes advertising expenses, onboarding, and training processes; this does not only include internal promotions but also hires from outside the organisation. 

The cost per hire will depend on the nature of the position or positions being advertised, the strength of in house recruitment and the size of the organisation; some organisations (particularly in larger ones), outsource to a recruitment agency to fill in the positions on their behalf at a fixed fee per candidate, which will be included in the cost per hire.