Direct Hiring: If you pay casual labourers directly as your own temporary workers, GST generally does not apply.
Contractor Hiring: If you use a third-party agency or contractor to supply labour, the service is almost certainly taxable at 18%.
Compliance: Always verify if your contractor is GST-registered. If they are not, consult your tax advisor to determine if you are liable to pay tax under the Reverse Charge Mechanism (RCM).