The minimum frequency for undertaking checks is defined in relevant legislation.
For example, the Lifting Operations and Lifting Equipment Regulations 1998 (LOLER) states that:
"every employer shall ensure that lifting equipment which is exposed to conditions causing deterioration which is liable to result in dangerous situations is thoroughly examined —
in the case of lifting equipment for lifting persons or an accessory for lifting, at least every 6 months;
in the case of other lifting equipment, at least every 12 months"
Most organisations will find that they have to comply with many regulations, each of which can specify different compliance tasks, each with a different timetable.
To help you get started, we've produced a free compliance calendar template. It lists some of the most common checks required and the timetable for doing so.