Severability clauses in Australian contracts, what they do and when they fail

If one clause in your contract turns out to be invalid, illegal or unenforceable, does the whole agreement collapse? Usually not. A severability clause says that a defective term can be removed and the rest of the contract keeps operating. It sits quietly in the boilerplate section of most commercial agreements, but it does real work when a dispute arrives.

This article explains what a severability clause is, how Australian courts approach it, and where the Australian Consumer Law gives you some of the same protection automatically. It then works through a realistic example, the common misconceptions that cost business owners money, and when a lawyer should review your contracts.

What a severability clause actually does

A severability clause operates in two steps. First, it identifies what happens if a term of the contract is void, invalid, illegal or unenforceable: that term is severed, meaning it is treated as if it was never part of the agreement. Second, it states that the remaining terms continue in full force and effect.

The purpose is to stop one defective provision from bringing down the whole bargain. Businesses rely on it when a clause has been drafted too broadly, when it conflicts with a statute, or when the law changes after the contract was signed. A limitation of liability that overreaches, a restraint of trade that is wider than necessary, or a term the Australian Consumer Law makes void can each be removed without destroying the deal around them.

The blue pencil rule: courts strike out but do not rewrite

Australian courts apply what is commonly called the blue pencil approach to severance. They can strike out offending words or clauses, much as an editor might delete them with a blue pencil, where the remaining text still makes sense as a standalone promise. What they will not do is rewrite the contract for the parties.

That distinction matters. If deleting words leaves a complete, sensible clause behind, the court can sever. If the clause needs new words added, or a period shortened from five years to two, the court is being asked to make a new bargain, and it will refuse. The result is that an overbroad clause often fails entirely rather than being trimmed to something reasonable.

This is why drafting matters more than the severability clause itself. A clause drafted as one indivisible promise gives the court nothing to save. A clause built from separate, self-contained options gives the court something workable to enforce.

Reading down and cascading options

There are two drafting techniques that improve your position when a clause goes too far:

• Reading down: Some contracts say that an invalid term should be read down to the minimum extent necessary to make it valid. This does not authorise a court to rewrite the clause, but it can support a construction that preserves a workable meaning where the language reasonably allows one.

• Cascading alternatives: A restraint of trade, for example, can be drafted as a series of decreasing time periods and geographic areas, with each option stated as a separate promise. If the broadest option is unreasonable, the court can enforce the next option down that is reasonable.

The New South Wales Court of Appeal confirmed how this works in Hanna v OAMPS Insurance Brokers Ltd [2010] NSWCA 267. The former employee's deed contained a cascading clause with nine restraints, from the widest at 15 months across Australia down to 12 months in metropolitan Sydney. The court held the cascade was not void for uncertainty and enforced a reasonable option from the series. Without the cascade, an overbroad restraint risks being struck out in full.

Severance already built into the Australian Consumer Law

For consumer and small business contracts, some of this protection is statutory. The Competition and Consumer Act 2010 (Cth) (the CCA) contains the Australian Consumer Law (the ACL) as Schedule 2. Under s 23 of the ACL, an unfair term in a standard form consumer contract or small business contract is void, and the contract continues to bind the parties if it is capable of operating without that term.

A small business contract for these purposes is one where at least one party has fewer than 100 employees or an annual turnover under $10 million. The unfair terms regime covers standard form contracts in both directions, so a business's own terms with its customers and the terms it accepts from suppliers can both be caught.

Two things are worth noting about this statutory severance. First, it operates automatically, so you are not relying on your own drafting. Second, the stakes have risen: since the regime was strengthened, proposing an unfair term in a standard form consumer or small business contract, or applying or relying on one, can attract a pecuniary penalty. A severability clause does not insulate you from that exposure.

The ACL also voids terms that try to contract out of rights it makes non-excludable. Under s 64 of the ACL, a term is void to the extent it purports to exclude, restrict or modify the consumer guarantees that apply to the supply of goods or services. A line saying "we accept no liability whatsoever" cannot remove a customer's right to a repair, replacement or refund, no matter how carefully the rest of the clause is worded.

A worked example: selling a business

Marta sells her café to Daniel. The contract contains a clause stating that Marta will not carry on or be employed in any café business in Australia for five years. The price reflects the goodwill Daniel is buying, and the restraint is meant to protect it.

The restraint is plainly wider than necessary to protect that goodwill. Six months after the sale, Marta opens a café in the next suburb, and Daniel sues to enforce the restraint.

A court will not rewrite the clause into, say, two years within a five kilometre radius. If the restraint was drafted as one indivisible promise, it is likely to be struck out entirely, and Marta is free to compete, subject to any separate confidentiality obligations she signed. If the contract had instead set out a series of alternative restraints of decreasing scope, as in Hanna v OAMPS, the court could have enforced a reasonable option from that series and Daniel would have received meaningful protection.

Either way, the rest of the sale contract survives. The price, the handover of the business, and the transfer of the name and equipment all continue to operate because of the severability clause. The deal is not undone; only the defective restraint is. That is the point of the clause in action.

Common misconceptions about severability

Business owners commonly overestimate what a severability clause can achieve. These are the mistakes we see most often:

• A severability clause can make an unlawful clause enforceable: It cannot. If a term is void because it excludes non-excludable consumer guarantees under s 64 of the ACL, or because it is an unfair term under s 23, severability does not validate it. The term fails regardless; the clause only helps the rest of the contract survive.

• Courts will cut an overbroad restraint down to something reasonable: Only if the drafting gives them something to work with. Without cascading alternatives, or language that permits reading down, the court will not perform the surgery for you. The whole restraint fails, and the protection you thought you bought is gone.

• Without a severability clause, the entire contract is void: Not usually. Courts can sever at common law even without an express clause, and the ACL does it automatically for unfair terms. But you take on real uncertainty. If the invalid term is central to the bargain, or the contract was structured as an indivisible whole, severance may not be available and the whole agreement can fail, as the High Court recognised in SST Consulting Services Pty Ltd v Rieson [2006] HCA 31 in the context of an agreement found to be an indivisible arrangement.

• A severability clause protects you from penalties under the unfair terms regime: No. The penalty exposure attaches to proposing or relying on an unfair term in a standard form contract, not to the presence or absence of a severability clause. The way to manage that risk is to remove the unfair terms in the first place.

• Severability fixes the contract but not the relationship: Severance can leave a hole where an important protection used to be. If the severed term was core to the deal, such as the pricing mechanism or a key performance obligation, the surviving contract may be commercially unworkable, and the parties are left to renegotiate or terminate.

When to get a lawyer to review your contracts

A severability clause is a few lines of boilerplate, but the provisions it interacts with are where the risk lives. A lawyer's value here is in checking those interactions before a dispute does.

A commercial lawyer reviewing your contracts will look at whether each risky clause is drafted in severable form, whether your restraints of trade use cascading options that a court can enforce, whether your liability and warranty language acknowledges the consumer guarantees and other non-excludable rights under the ACL, and whether your standard form terms would survive scrutiny under the unfair terms regime. Where severance would leave a hole in the deal, they can draft a fallback mechanism, such as a renegotiation or variation pathway, so the parties are not left with an unworkable contract.

For a business that runs on standard form agreements, such as website terms, supply terms or employment contracts, this review is usually quick and pays for itself. It converts boilerplate you have never read into protection you can rely on, and it identifies the clauses that would have failed you in a dispute.

The question to ask about your own contracts

The single most expensive misconception in this area is that a severability clause rescues a badly drafted clause. It does not. It only decides what happens to the rest of the contract once the bad clause has failed.

So ask yourself this about the contracts your business relies on: if the weakest clause were struck out tomorrow, would the rest of the deal still work, and would you still be protected where it matters? If the answer is no, the fix belongs in the clause itself, not in the boilerplate beside it.