The IRD says there is no way for it to identify from an employer monthly schedule - the tax information employers send to the IRD - whether an employee is eligible or not to be a member of KiwiSaver.
"It is the employer's responsibility to apply the rules and to make the correct deductions from their employee's wages or salary," it says.
"It is the employee's responsibility to check that those deductions are being made."
Employees need to keep an eye on their payslips, but the IRD's online myIR service will also track pay deductions, employer's contributions and any member tax credits earned.
KiwiSaver providers are also legally required to provide updates at least once a year, but most will be in touch more regularly.
If you're not hearing from your provider or your payslips aren't showing any deductions it's definitely time to take action.
In the first instance you need to talk to your boss.
If you aren't happy with the response call the IRD. You need to do this as soon as possible.
The IRD says if an employee thinks deductions or contributions haven't been made they need to contact it within 12 months of starting a new job.
"If they do so then compulsory employer contributions can be backdated to the start of the employment," it says.
If more than a year has passed before the IRD are told about the problem, contributions will only need to start from the day before the IRD sends a letter to the employer requesting KiwiSaver contributions/deductions begin.
"Deductions not made from the employee's wages cannot be backdated, although the employee could make a voluntary contribution."
The HomeStart grant, administered by Housing New Zealand separately from the KiwiSaver first-home withdrawal, requires at least three years of regular contributions.