Using this API product
Description
Most purchasers of new residential premises or potential residential land are required to withhold an amount from the contract price for payment to the ATO under the GST at settlement measure.
Where the purchaser has received written notification from the supplier that withholding is required in the contract of sale or a separate document before settlement, the purchaser or their authorised representative (conveyancer or solicitor) can use this API product to lodge the required GST property settlement forms via their software products, directly to the ATO, covering the following obligations:
Lodge Form one: GST property settlement withholding notification
Form one is to be lodged any time after a contract of sale has been entered into and you have written notification from your supplier there is a requirement to withhold. Form one must be lodged by the due date for payment of the withholding amount; this is usually settlement date or the first instalment date.
Form one notifies the ATO that a purchaser has entered into a contract and has a withholding obligation.
Lodge Form two: GST property settlement date confirmation
Form two is to be lodged for:
- a standard land contract, either:
- within 2 business days before settlement
- on the day of settlement
- on the next business day after settlement
- an instalment contract – when the first instalment is paid.
Form two confirms your settlement date and establishes a purchaser withholding account, where your withholding liability is recorded until payment is made.
- a standard land contract, either:
Pay the withholding amount to the ATO (to the nearest dollar).
The payment is due either on the day of settlement (for a standard land contract) or the day the first instalment is paid (for an instalment contract). You can use your software to electronically transfer funds to the platform and the withholding payment will be made directly to the ATO.
The lodging entity can submit an original Form one lodgment via this API Product. You will receive a lodgment confirmation response, which includes the lodgment reference number (LRN) and a payment reference number (PRN) required to lodge Form 2 and to make the associated withholding payment.
For information if an error is identified on the GST property settlement form lodgment, go to How to amend or cancel your forms.
For further information go to GST property settlement online forms and instructions.
Business usage and process flow
The API product provides a suite of functionality that allows the adoption, design and lodgment of the GST property settlement forms. The API product enables this by providing an API with 4 endpoints that can be used to lodge and provide PRN’s for lodging Form two and making payments towards liabilities reported.
The GST Property Settlement API in the API Product has multiple endpoints that can be used to deliver this functionality.
- To submit the GST Property Settlement Withholding Notification form
Call the Endpoint: POST /propertySettlements - To validate the lodgement data for GST Property Settlement Withholding Notification form
Call the Endpoint: POST /propertySettlements/validationResults - To submit the GST Property Settlement Date Confirmation form
Call the Endpoint: POST /changeOfPropertySettlements - To validate the lodgment data for GST Property Settlement Date Confirmation formCall the Endpoint: POST /changeOfPropertySettlements/validationResults
Lodging entity
- The lodging entity will be able to lodge the GST property settlement forms via the use of the above-mentioned API
- Upon successful response from the above-mentioned API the ATO will receive the lodged GST property settlement forms
ATO
- ATO will return a lodgment confirmation or any errors that may happen during the lodgment of the GST Property withholding notification (Form one) or GST property settlement date confirmation (Form two)
- A PRN and LRN will be returned upon the lodgment of the GST Property withholding notification (Form one).
Instruction to Digital Software Developers (DSP) for lodgment of Form two.
- To lodge Form two: GST property settlement date confirmation using the GST Property Settlement API (POST /changeOfPropertySettlements), ensure you use the LRN and PRN of the successful lodgment of the Form one: GST property settlement withholding notification form, which is available in the GST Property Settlement API (POST /propertySettlements)
Authentication
Authorisation
The lodging entity can be the property purchasers or their representative (a conveyancer or solicitor).
The purchaser can authorise a representative to lodge the GST Property Settlement forms on their behalf via a signed declaration. The authorised representative must have appropriate authorisation for the interaction being performed on behalf of the purchaser recorded in ATO systems.
For more information around how to ensure everything is setup correctly for authorisation calls to the API product refer to About Access Manager.
Scopes
ato.apGSTPropertySettlement
End User
End users that will submit GST Property Settlement forms using this API product are:
- Reporting party (Property purchaser)
- Intermediary – not a registered agent (Representative authorised by the purchaser)
Risk rating
4 – High Risk
For more information, see API risk rating.
Rate Limit
Not Applicable
Test Scenarios
The GST Property Settlement Test Scenarios are provided in the sandbox environment to guide you in the development of your application software.
Testing of the mandatory test scenarios is a mandatory requirement before production access is granted.
Production requirements
Before you can request production access for this API Product, you must meet the requirements for production access.
Constituent API
API List
GST Property Settlement API
API specification
Release notes
16 April 2026
Initial version published for consultation.