An apostille is not something a private practitioner can issue. It is a government certificate, applied by the Department of Foreign Affairs and Trade as Australia's competent authority under the Hague Convention. DFAT is a government department with published opening hours, and no notary, agent or courier can make it open earlier.
So the honest answer to "can I get an apostille after hours?" is no — but that is not the end of the question, because an apostille is the last link in a chain, and the links before it are where evenings and weekends actually buy you something.
A document bound overseas usually passes through three stages:
Stage 1 is the only stage with any flexibility in its hours, because it is the only stage performed by someone who sets their own diary. Stages 2 and 3 run on government and diplomatic-mission time, and missions often keep shorter public hours than DFAT does.
This matters for planning. If you find a notary willing to see you at nine on a Sunday night, you have not gained a day — you have gained a position at the front of Monday's queue. That is sometimes worth a great deal, and sometimes worth nothing at all.
In each case the value is in removing the notarial appointment from the critical path, not in accelerating DFAT.
If the document has not yet been issued, or is a copy of a record you still need to obtain from a registry, or requires a translation that has not been done, an after-hours notarial appointment simply relocates the bottleneck. The same is true if the receiving country is outside the Hague Convention: an embassy that takes documents in for legalisation on set days will do so on those days regardless of when the notary signed.
DFAT publishes how documents may be lodged for an apostille, including in-person and postal options, and the current fee. Those details change, so check the DFAT legalisation pages rather than relying on any third-party page, including this one, for the specifics.
What is worth knowing structurally:
Be wary of any service that implies it can obtain an apostille outside DFAT's published hours, or guarantees a same-day apostille as a matter of course. Treat both as claims to verify, not facts.
Before paying an after-hours premium to compress a timeline, confirm that the document you are rushing is the document that will be accepted. Three questions to the body that will receive it:
If the destination is outside the Hague Convention, an apostille is the wrong certificate entirely, and speed will not save it.
Practitioners who offer evening, weekend or callout appointments generally charge a premium over their standard fee, and mobile attendance is usually charged separately again. The size of that premium varies widely between practitioners and cities, so ask for it in writing before booking rather than assuming a market rate. DFAT's own fee does not change according to when you lodge.
Can anyone issue an apostille outside DFAT? No. In Australia, DFAT is the competent authority for apostilles. A notary, lawyer or agent cannot issue one, and a document that claims otherwise is not an apostille.
Is there an emergency or expedited apostille service? DFAT publishes its current processing arrangements and any priority options. Because these change, confirm directly rather than relying on a figure quoted on a commercial website — including a quoted number of days.
I have an apostille but the embassy still wants more. Then the destination is probably not a Convention country, or the document type sits outside what the Convention covers. Go back to the receiving authority and ask exactly which certificate it requires.
Does a weekend notarisation look less legitimate? No. A properly executed notarial act is valid whenever it was performed. What matters is the identification, the register entry and the seal, not the hour.