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.
The purchaser will receive written notification from the supplier if there is a requirement to withhold or not, this is provided in the contract of sale or a separate document before settlement.
Where written notification from the supplier has been received that withholding is required the purchaser's 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.
- 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 further information go to GST property settlement online forms and instructions | Australian Taxation Office.
Business usage and process flow
The API product provides a suite of functionality that allows the lodgment of the GST property settlement forms. The API product contains an API that can be used to perform a precheck of the lodgment data and to lodge Form 1 and 2. The API will provide PRN’s for lodging Form two and making payments towards liabilities reported.
Guidance for Digital Software Providers (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) response.
Cancellation of Form one and Form two
- Form one can only be cancelled where the withholding amount has not been paid (and it is not on its way to the ATO) by either:
- Calling the ATO or,
- Following guidance for DSPs to allow their users to cancel in software. Visit GST on Property Settlement Cancellation | DSP Hub for more information
- If either both forms or just form two needs to be cancelled, call the ATO.
To find out more including valid reasons for amendment and cancellations, go to How to amend or cancel your forms | Australian Taxation Office
Authentication
See Client Authentication | ATO API Portal
Authorisation
The purchaser can authorise a representative (conveyancer or solicitor) to assist them in the withholding process via a signed declaration.
The purchaser's representative must understand their obligations under the Tax Agent Services Act 2009 (TASA).
Online (cloud) DSPs must have their Software Subscription ID (SSID) linked to the lodging entity's ABN through ‘Notify the ATO of a hosted service’ in Access Manager. This linkage allows the Purchaser's representative (the authorised intermediary) to use the DSP’s software to access available services
Scopes
ato.apGSTPropertySettlement
End User
End users that will submit GST Property Settlement forms using this API product are:
- Reporting party (including representative)
Risk rating
4 – High Risk
For more information, see API risk rating.
Rate Limit
Not Applicable
Test Scenarios
The GST Property Settlement API 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
04 June 2026
Initial Release (Sandbox)
Product description
- Added further information on the process of lodging, obligations needed of purchaser's representative and removed purchaser as lodging party.
Business usage and process flow
- Provided guidance and instructions on cancellation of form one lodgment.
Authorisation
- Removed purchaser as lodging entity, making purchaser's representative as the only authorised lodging entity for the API.
End User
- Removed Reporting party (Property purchaser) from the list of end users.
Test Scenarios
- Provided mandatory test scenarios which are a mandatory requirement before production access is granted.
- Provided recommended test scenarios for additional testing to ensure optimal user experience.
Response Messages
- Provided a list of common response messages and API specific response messages with trouble-shooting information.
GST Property Settlement API
- Open API Specification (OAS)
- Updated API endpoints to include identifierValue as a path parameter
- Updated Request schema
- lodgedBy enum list changed to have "REPRESENTATIVE" only
- representativeBusinessName changed to be mandatory
- PurchaserContact renamed to ContactDetails - Removed examples where lodgment is submitted by a Purchaser
16 April 2026
Initial version published for consultation.