Mainfreight + ReturnMate
Mainfreight is one of the few carriers that handles both Australian and New Zealand domestic freight from a single API, with dangerous-goods capability across both markets. Useful for trans-Tasman merchants and any AU operation that outgrows AusPost size limits or needs a depot drop-off network outside the AusPost / Australia Post Group.
What the integration does.
- REST API integration covering shipments, rates, labels, and tracking
- AU and NZ domestic freight from one account
- Dangerous-goods support across both markets
- Multi-item consignments with consolidated tracking number
- Live rate quoting for the customer portal
- Tracking webhooks plus polling fallback for partial coverage areas
How merchants use it.
Trans-Tasman returns
AU customer ships back to a NZ warehouse (or vice versa) on a single Mainfreight consignment without needing two carriers and two label generations. Customs documentation surfaces in the same record.
Heavy non-DG freight beyond AusPost limits
For RMAs with parcels over 22kg or 1.05m on any side, AusPost won't accept the booking. Mainfreight does, with the same branded-label experience and tracking surface.
DG returns under or over 22kg
Unlike AusPost (no DG) or StarTrack (DG up to 22kg), Mainfreight handles DG shipments at any weight. ReturnMate routes automatically based on the SKU's DG flag and weight.
Connect Mainfreight in minutes.
- 1
Add Mainfreight credentials
Settings → Carriers → Mainfreight. Enter your Mainfreight account number and API key. Choose AU, NZ, or both as the active markets for label generation.
- 2
Pick service codes per direction
Configure default services for B2B freight vs B2C. Defaults are sensible for most merchants; override per location if needed.
- 3
Generate a test consignment
Generate a test label from Settings → Carriers to verify the credentials work end-to-end. For trans-Tasman testing, run one AU-origin and one NZ-origin test.
Questions about Mainfreight.
Does Mainfreight handle dangerous goods in both AU and NZ?
Yes. Mainfreight is one of the few carriers that supports DG shipments across both Australian (ADG) and New Zealand (Land Transport Rule) compliance frameworks from a single account. ReturnMate generates the appropriate transport documents for whichever market the shipment originates in.
When should I pick Mainfreight over AusPost or TGE?
Three cases: (1) the parcel is over AusPost's size or weight limits (22kg / 1.05m), (2) you need DG capability without the StarTrack 22kg cap, or (3) you operate trans-Tasman and want a single-carrier story. For domestic AU non-DG under 22kg, AusPost is usually cheaper.
How does Mainfreight tracking compare to AusPost or NZ Post?
Mainfreight's tracking is consignment-level rather than parcel-level — useful for multi-item shipments where you want one tracking ID for the whole RMA. Event granularity is comparable to AusPost; less frequent than express services like TNT.
Also integrated.
Australia Post
MyPost Business labels, PAC rates, branded labels, address validation.
Read more CarriersStarTrack
Premium freight with dangerous-goods capability, eParcel labels, DG transport docs.
Read more CarriersTNT (FedEx)
Express labels with pickup scheduling, dangerous goods capability, real-time pickup windows.
Read more CarriersTeam Global Express
National freight with depot drop-off network, multi-item consignments, PrintDocument labels.
Read more CarriersNZ Post
NZ domestic labels, eShip rates, address validation. OAuth2 REST integration for New Zealand merchants and inbound returns.
Read moreReady to connect Mainfreight?
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