Subclass 300 Lodgement in 2026: TRN, Sponsorship Timing and Attaching Documents

Once a Prospective Marriage visa (subclass 300) application is paid for and submitted in ImmiAccount, the applicant receives a transaction reference number (TRN), and that TRN is what the sponsor needs in order to lodge the sponsorship; the sponsor is expected to apply to sponsor as soon as possible after the visa application goes in, and any documents not attached at lodgement can still be uploaded afterwards in ImmiAccount as soon as they are ready. This follows the Department of Home Affairs' official "Prospective Marriage visa (Subclass 300)" page, as of July 2026. The same page sets out the online application path, the 100-document attachment ceiling per person, and the channels for material that cannot be uploaded.

What actually has to be true at the moment of lodgement?

Three conditions sit on the applicant at the point of applying, and they are not interchangeable with the conditions that apply later.

The application must be made online, and the applicant must be outside Australia when applying, along with any family members applying at the same time.
The applicant must be 18 or older, intend to marry the prospective spouse before the visa period ends, and have met that person face to face as adults since turning 18, known to each other personally at the time of application.
The applicant must have a sponsor who is an Australian citizen, Australian permanent resident or eligible New Zealand citizen — both when lodging and while holding the visa.

The Department's page also states the Department cannot process an application if the correct visa application charge is not paid. No fee figure should be assumed from this article; the charge is set out on the official pages and changes over time.

Where does the TRN come from, and who needs it next?

The TRN is generated in the ImmiAccount sequence described on the Department's page: log in, select 'New application', select 'Family', select 'Stage 1 – Partner or Prospective Marriage Visa', complete the form, pay the visa application charge, then submit. Step 8 of that sequence is explicit: give the TRN to the sponsor, because the sponsor needs it to apply for sponsorship.

In practice the handover is the failure point. Two details from the official page reduce the risk:

The TRN is not the only identifier that works. The "After you apply" section says to give the sponsor your TRN or application ID, so a sponsor blocked on one identifier can be unblocked with the other.
Contact details matter independently of the TRN. The partner visa form asks for the applicant's own phone number and email, because the Department may need to contact the applicant directly even if the sponsor's email was nominated, an authorised recipient was appointed, or someone was appointed to give immigration assistance.

Handover element	Who holds it	What it unlocks
TRN or application ID	Applicant, passed to sponsor	Sponsor's sponsorship application
Applicant's own contact details	Applicant, entered in the form	Direct contact from the Department
Supporting documents	Applicant, uploaded in ImmiAccount	Assessment of relationship, identity, character, health

When should the sponsorship be lodged?

As soon as possible after the visa application. The Department's page states this once in the document-gathering step ("Your sponsor should apply to sponsor you as soon as possible after you apply for this visa"), and separately, after lodgement, presents giving the sponsor the TRN or application ID as the trigger for the sponsorship application.

The sequencing matters because the sponsorship is a separate action by a separate person, not a field on the applicant's form. A submitted visa application with no sponsorship behind it is simply waiting on an act the applicant cannot perform. Assuming an applicant hands over the TRN the same day, the sponsorship can follow within that window; assuming the TRN sits unread for weeks, nothing in the applicant's own application moves in the meantime.

How many documents can be attached, and what happens at the limit?

Each person on the application can have up to 100 documents attached, and the Department states plainly that the attachment limit cannot be increased. If the limit is reached for one applicant, further documents can be attached to other clients on the same application.

Two related rules from the page matter more than the number itself:

Label documents clearly and attach each document only once, even where it supports more than one point.
Documents do not need to be certified. They do need to be scanned or photographed in colour and legible, multi-page documents saved as one file, and anything not in English translated, with Australian translators accredited by the National Accreditation Authority for Translators and Interpreters and overseas translators including their full name, address and telephone number, and qualifications and experience in the language they are translating, with these details provided in English on each translation.

How fast do post-lodgement documents have to follow?

There is no fixed deadline stated on the page; the standard is "as soon as you can" for documents that were not attached at lodgement, and "as soon as possible" for documents supplied after the application in general. The practical pressure comes from elsewhere:

Police certificates are valid for 12 months from the issue date, and if more than 15 months has passed since an Australian Federal Police National Police Certificate was issued, new checks will be required to progress the application.
Health assessment results are valid for 12 months from the time the examinations were completed; a health undertaking, if one is signed, is valid for 6 months. The Department suggests checking published visa processing times before deciding when to complete health examinations.
The ImmiAccount checklist is the mechanism the Department points to for confirming that required documents are included, and the Department states that applications lodged with all required information reduce processing delays.

Where documents genuinely cannot be uploaded, the Department's page identifies the Partner Processing Enquiry Form as the channel to use. If an application is within standard processing times, the Department asks applicants not to seek progress updates, since no further information can be given; requests for more information show up in ImmiAccount.

What changes the shape of the application after lodgement?

Some post-lodgement events are routine, and at least one ends the subclass 300 pathway entirely.

A dependent child can be added before a decision is made, using Form 1436, provided the child is outside Australia; the Department then asks to be notified through the Partner Processing Enquiry Form.
Marriage before the decision removes eligibility. The applicant must notify the change in ImmiAccount, attach evidence of a valid marriage, request consideration for the Partner (Provisional) visa (subclass 309) and Partner (Migrant) visa (subclass 100), and state that the subclass 300 application is withdrawn. Without withdrawal, the application will be refused for no longer meeting eligibility.
Help arrangements are documented, not assumed. Appointing someone to receive correspondence uses Form 956A; appointing someone to give immigration assistance uses Form 956, and that person must be a registered migration agent, a legal practitioner or an exempt person. Withdrawing either arrangement uses the same forms.

This article is general information about the published process, not advice on any individual case, and anyone applying should check the current official pages or obtain advice from a properly registered practitioner before acting.

Frequently Asked Questions

Do I need to attach every document before I submit the application?

No. The Department says you should provide all required information with the application or as soon as possible after lodging, and documents not attached at lodgement can be uploaded in ImmiAccount afterwards. Lodging with everything attached does reduce processing delays.

What is the TRN for, and does the sponsor need anything else?

The TRN is the reference your sponsor needs to apply for sponsorship. The Department also accepts the application ID for this purpose, so either identifier will let the sponsorship application proceed.

Can the 100-document limit be raised if my case is document-heavy?

No. The Department states the limit of 100 documents per person cannot be increased. If one applicant reaches the limit, further documents can be attached to other clients on the same application instead.

How long do police certificates and health results stay valid for a subclass 300 application?

Police certificates are valid for 12 months from the issue date for immigration purposes, and health assessment results are valid for 12 months from when the examinations were completed. An Australian Federal Police National Police Certificate older than 15 months will require new checks.

What happens if we marry while the subclass 300 application is still being decided?

You are no longer eligible for the visa. You must update ImmiAccount, provide the registered marriage certificate, request consideration for the subclass 309 and subclass 100 partner visas, and state that you want to withdraw the subclass 300 application; otherwise it will be refused.

Can I travel to Australia while the application is being processed?

The Department's instruction is not to arrange travel to Australia until it advises in writing that the subclass 300 visa has been granted. If you do travel on another visa, you remain responsible for holding a valid visa for the whole stay.