Tax code declaration (IR330)
Every new employee must fully complete a Tax code declaration (IR330). The tax code declaration will tell you as an employer what rate of tax you need to deduct from their wages.
If an employee fails to fully complete the IR330 you must deduct tax at the no-notification rate.
You must keep the completed IR330 with your business records for seven years following the last wage payment you make to an employee.
Tax rate notification for contractors (IR330C)
Every new contractor receiving schedular payments must complete a Tax rate notification for contractors (IR330C). The contractor will show the tax rate they want to use - either the standard rate for their activity as shown on page 3 of the IR330C or a rate of their own choosing, subject to minimums. If no rate is shown use the standard rate for the activity.
You must keep the completed IR330C with your business records for seven years following the last payment made to the contractor.
If the contractor doesn't give you a completed IR330C or doesn't give you the IR330C at all, you must deduct tax at the applicable no-notification rate.
Enrol your employee in KiwiSaver
Employees who start a new job and meet the criteria for automatic enrolment must be enrolled in KiwiSaver, unless you offer an approved alternative superannuation scheme. You must provide KiwiSaver information to all new employees and to any existing employees who ask for the information.
Keep a wage record
It's a legal requirement that you maintain full records for all your employees and contractors, including for each payday each employee's total gross earnings and taxable and tax-free allowances, the amount of PAYE and other deductions, and any payroll giving donations and tax credits.
Business.govt.nz has more information on keeping employee records.
There is also a wage, time and leave record template available from the Ministry of Business, Innovation and Employment (MBIE).