Overtime is work which staff are required to undertake in excess of their conditioned hours. Overtime should normally be authorised in advance by departmental management, and be compensated by Time Off. If granting of Time Off is considered not practicable within one month after an officer has undertaken overtime work, an Overtime Allowance (or Disciplined Services Overtime Allowance for disciplined services staff) may be payable to eligible officers.

Rules are set out in the Civil Service Regulations and CSB Circular No. 18/2000.

When an officer is required to stand by at the place of work in excess of the conditioned hours, a Stand-by Duty Allowance may be payable to eligible officers. If an officer is regularly required to be immediately available for duty if called upon to do so during any period beyond the conditioned hours, an On-call Duty Allowance may be payable to eligible officers.