A commercial lease has just landed on your desk, and the execution block invites the company to sign by affixing its common seal. Or the bank's facility documents ask whether the company has one. If you incorporated in the last few years you may never have ordered a seal stamp, and you are now wondering whether the company is missing something it is supposed to have.
The short answer is that under Australian law a company seal is entirely optional. Section 123 of the Corporations Act 2001 (Cth) (the Act) says a company may have a common seal, not that it must. A company that never orders a stamp is no less "official" than one that does, and director signatures can execute every document a company needs, including deeds. The real decision is not "do I have to buy a seal?" but "will having one make my company's signing easier or harder?"
Two assumptions are worth clearing up before you weigh that. First, the seal is not the company's signature in the way many people assume. Under s 127 of the Act, documents are executed by the officers who sign and witness them, with or without a seal. Second, "company seal" can mean two things: the legal concept of a common seal, and the physical stamp or embosser you order from a stationer. Only the first matters to the law, and the law does not require it. So the practical question is whether the physical stamp earns its place in your drawers.
Your options in short
You have two workable options, and they are not as different in legal effect as the marketing of seal stamps suggests:
- Option one — adopt a common seal: You order a stamp that carries the company's registered name and its ACN, keep it somewhere secure, and apply it to documents in the execution blocks that call for it. The stamp itself costs little, but it brings a small compliance and governance load with it.
- Option two — skip the seal entirely: You execute documents by director signatures under s 127(1) of the Act, which is exactly what most Australian companies do. Every document the company needs to sign, from a service agreement to a deed of guarantee, can be executed this way.
There is no third option of "being more official" by having a seal. A bank, landlord, or overseas supplier cannot demand that Australian law force you to hold one, because the law does not. What they can do is ask for one as a matter of their own process, which is a factor worth weighing rather than a legal requirement.
The factors that matter
The decision comes down to a handful of practical considerations. Here is what to weigh.
What the law actually requires
The legal baseline is simple and it is worth holding onto. A company may have a common seal, and if it does, the seal must set out the company's name and its ACN, or its ABN where the last nine digits of the ABN match the ACN, unless the ACN is already part of the company's name. That is the whole of the content requirement in s 123(1) of the Act. It is also an offence, one of strict liability, to use a seal that purports to be the company's common seal but does not comply. So if you do order one, the engraving has to match your ASIC registration exactly, including the "Pty Ltd" if your name carries it.
If you want more than one stamp, s 123(2) allows a duplicate common seal, but the duplicate must be a copy of the original with the words "duplicate seal", "share seal" or "certificate seal" added. That is a small detail, but it is the kind of thing that is easy to get wrong when a second office orders its own stamp.
The Act is equally clear that you can execute documents without a seal. The small business guide at the front of the Act puts it in plain terms: a company can deal with contracts without using a common seal. Section 127(1) then sets out exactly how. This matters because it means the seal is never a condition of validity. A document signed the right way without a seal is as effective as one with the seal pressed onto it.
Who will be signing, and how often
Execution under s 127(1) works through the officers who sign, and the permitted combinations are:
- Two directors: the standard combination for most companies.
- A director and the company secretary: the alternative where a secretary is appointed.
- A sole director of a proprietary company: that director alone can sign, where they are also the sole company secretary or the company has no secretary.
If your company has a sole director who is also the sole secretary, or no secretary at all, one signature is enough for everything, and a seal adds nothing to that. The same combinations apply if you do use a seal: s 127(2) requires the fixing of the seal to be witnessed by those same officers.
Separate from s 127 is the question of authority for day-to-day documents. The small business guide notes that a company's power to sign and otherwise deal with contracts can be exercised by an individual acting with the company's authority and on its behalf. That is how employees end up signing routine supplier forms and purchase orders without any director involvement. A seal does not change that picture, because the seal has nothing to do with who holds authority for operational documents. If you want staff to sign routine documents, the work is in setting up and documenting that authority, not in buying a stamp.
Frequency is the practical driver. If your directors sign documents every week, a process that depends on a physical stamp kept in a drawer will create friction and bottlenecks. If you sign a handful of formal documents a year, the seal is a minor cost either way. Note also that signatures can be electronic: the Act's technology-neutral signing provisions allow the requirement to sign to be satisfied electronically, and s 127(2A) even allows the fixing of a seal to be witnessed by electronic means. A physical stamp sits awkwardly alongside a mostly digital signing workflow, which is one reason many modern companies never buy one.
What the other side of the table expects
Seal requests usually come from one of three directions, and in each case they are about the other side's process rather than Australian law:
- Banks and finance providers: facility documents sometimes ask whether documents were sealed, witnessed, or signed in a particular way, because their internal compliance checklists expect it.
- Landlords and property agents: commercial lease packs occasionally request a seal out of habit, or as a belt-and-braces measure even though director execution is sufficient.
- Overseas counterparties: in some jurisdictions sealing is the normal way companies sign, so a foreign party may expect it even though it is not required here.
Where a counterparty insists, you have two paths: supply a compliant seal, or negotiate the execution clause so the document is signed by officers under s 127(1). The second path is usually open, because the document is no more enforceable for having been stamped. But you should decide before you reach the signing table, because renegotiating an execution block mid-deal is exactly the kind of delay a seal is meant to avoid.
Whether you are signing deeds or other formal documents
Deeds attract the most seal mythology. Guarantees, indemnities, releases, settlements, and some property documents are commonly structured as deeds, and people assume a deed must be sealed because that is how deeds were historically authenticated. Under the current Act that is not the position. Section 127(3) lets a company execute a document as a deed if it is expressed to be a deed and is executed in accordance with s 127(1) or (2), seal or no seal. Section 127(3B) confirms delivery is not necessary, and s 127(3A) allows a deed executed under s 127(1) to go without witnessing and in electronic form.
Where the seal question does bite with deeds is the drafting of the execution clause, not the act of sealing. The clause must match how the company will actually sign. If the clause says "executed by affixing its common seal" but nobody in the room can witness it properly, or says "signed by two directors" but the company has a sole director, the clause needs to be redrawn to fit the company's structure before anyone signs. That is a drafting task, and it is worth doing before the document is in front of you.
How much signing governance you want to run
A seal is only as good as the process around it. If you adopt one, you are taking on a small but real governance load: the stamp should be stored securely, access limited to a few authorised people, and records kept of what was sealed, when, and by whom. For some businesses that is a feature, because it creates a deliberate "big document" step. For others it is friction that nobody needs. Here is how the two options compare:
- Adopt the seal: makes sense if counterparties regularly ask for it, you sign many formal or property documents, or you want a visible extra step before major documents go out. The costs are ordering a compliant stamp, storing it securely, and keeping the register.
- Skip the seal: makes sense if directors sign routinely, most signing is electronic, and your standard execution clauses already follow s 127(1). The main cost is occasional pushback from a counterparty whose checklist expects a seal.
One caution either way: a seal that is applied without the right witnesses is worse than no seal, because it produces a record of a formal act that was never properly completed. If you are not prepared to run the process, the stamp is a liability rather than an asset.
When a lawyer should look at your signing process
If you are weighing this decision, an Artificer Legal practitioner can help in concrete ways. The first is checking the execution clauses of the documents you actually sign against your company's structure, so a deed or guarantee is not signed in a way that leaves it unenforceable. The second is confirming what your constitution says, if you have adopted one: s 127(4) preserves other ways of executing documents, including methods set out in a constitution, and the constitution may already contain rules about the seal.
A lawyer can also help where a counterparty insists on a seal, by drafting an execution clause that satisfies their process without creating risk for you, and by advising on what happens if a document is mis-executed. The Act gives people dealing with a company the benefit of assumptions that documents were duly executed, which can bind the company to something it did not intend, or the reverse: a company can be left with a document it cannot enforce because the signing was defective. Stress-testing which way that falls in a specific dispute is where legal advice earns its keep.
The decision that matters more than the stamp
The company seal is optional, and the thing people forget is that the stamp itself adds nothing to validity. It is the officers who sign and witness, in the combinations set out in s 127, that make execution effective. A seal applied without the right witnesses is worse than none, because it documents a formal act that was never completed. So the real decision is not whether to buy a stamp but whether your signing process matches the way the company is actually structured.
In short: you can skip the seal entirely and execute by director signatures under s 127(1), including for deeds, which need no seal and no witnessing when executed that way. If you do adopt a seal it must show your registered name and ACN, and the fixing must be witnessed by the right officers. Counterparty requests are about their process, not your legal obligations. And the work that actually protects the company, drafting execution clauses that fit who signs and how, is worth doing with a lawyer before the next important document lands on your desk.