GST Calculator

Help yourself to our handy tool for calculating your invoices & expenses:

GST Due Dates

For businesses with a March 31 balance day, the following applies:

Two Monthly GST

  • June 28: April/May GST Return & Payment Due

  • 28 August: June/July GST Return & Payment Due & 1st Provisional Tax Instalment Due

  • October 28: August/September GST Return & Payment Due

  • 15 January: October/November GST Return & Payment Due & 2nd Provisional Tax Instalment Due

  • February 28: December/January GST Return & Payment Due

  • April 7: Terminal Tax Due

  • ​7 May: February/March GST Return & Payment Due & 3rd Provisional Tax Instalment Due


​Six Monthly GST

  • 28 October: April/September GST Return & Payment Due & 1st Provisional Tax Instalment Due

  • ​7 May: October/March GST Return & Payment Due & 2nd Provisional Tax Instalment Due