Deposit, Excess and GST: Australian Rental Contracts Done Right

Most rental contract templates circulating among Australian operators are photocopies of photocopies — daily-hire terms stretched over weekly rentals, with clauses the ACCC declared unfair a decade ago still sitting in clause 14. That’s not a paperwork problem. The Federal Court voided Europcar’s standard damage-liability terms in 2016 and the company paid a $100,000 penalty for misleading representations about what renters owed. The contract is where your deposit, your excess and your tax treatment either hold up or fall over.

This is a walk through the four things an Australian weekly-rental contract must get right — deposit, excess, GST, signing — and the terms to keep out.

What must the contract say about the deposit?

That it is refundable security, what it can be applied to, and exactly how deductions happen — in writing, up front. The ACCC’s industry guide to the Australian Consumer Law for rental cars (2013, still the reference) is specific about the mechanics:

• State the amount and the forfeiture circumstances in writing. Australian bonds typically run $250–$1,100 for passenger vehicles; whatever yours is, the contract lists what it covers (unpaid rent, damage, cleaning) and under what conditions.
• No open-ended card authority. A clause letting you debit the renter’s card for whatever you later decide is exactly the kind of term the ACCC calls unfair. The contract authorises known amounts; anything unforeseen is itemised, notified and separately authorised before you touch the card.
• Itemise and evidence every deduction. Before drawing on the bond for damage, tolls or fines, provide an itemised bill and a reasonable opportunity to dispute it. Evidence means the paired condition reports — the ACCC expects a pre-existing damage report at handover with the renter given the chance to inspect and add to it, which is why paired photo inspections at delivery and return are the cheapest legal protection you can buy.
• Don’t make the renter liable for things outside their control. The guide’s own example: damage from vandalism after the car was returned on time but before you inspected it. Terms like that are unfair and void.

The full operational playbook — sizing, holding, releasing, deducting — is in security deposits done right. The contract’s job is to make every one of those steps something the renter already agreed to.

How should the insurance excess be written?

As a clear dollar cap on the renter’s liability, stated in the contract, fixed at signing. Three parts to getting it right:

The excess is a liability cap, not insurance. The damage cover bundled into a weekly rental caps what the renter pays when things go wrong — commonly somewhere in the $2,500–$5,000 band in the Australian market (National Cover). The contract must state the number, and if any situations sit outside the cap (single-vehicle accidents, water damage, negligence), those exceptions must be spelled out too. The ACCC’s position: if the headline excess isn’t a true ceiling, that has to be disclosed.

Age-banded excess is normal — write the bands down. Younger drivers carry statistically higher risk, and the market prices it: a higher excess for under-25s is standard practice across the segment. A typical structure is $3,500 for drivers 21–24 and $2,800 for 25 and over. Whatever your bands are, they belong in the signed document, not in a rate card you update later.

Snapshot the excess at signing. If you change your excess rules next quarter, every already-signed contract must keep the number the renter agreed to. This sounds obvious and is routinely botched by operators who store “the current excess” in one place and let it silently apply to old rentals. Carz handles this by resolving the excess from age-banded rules at contract generation and freezing that amount on the contract itself — later rule changes affect future contracts only. Whatever system you use, the signed PDF and the amount you’d actually charge must never be able to disagree.

How does GST work on weekly rentals?

Car rental is a taxable supply: the advertised price includes 10% GST, and the tax is extracted backward from the total, never added on top. The working numbers:

(Sources: the ATO’s GST registration guidance and business invoicing rules.) Two practical consequences. First, since every weekly payment clears the $82.50 line, “tax invoice on request” in practice means a tax invoice for every payment, every week, per car — 52 documents a year per vehicle. Doing that by hand is exactly the kind of admin that quietly stops happening; it’s worth automating (Carz generates a compliant tax invoice for every settled payment automatically, with the 10 ÷ 110 breakdown on each). Second, GST cuts both ways: the GST in your servicing, insurance and parts bills comes back as input credits on the BAS, which only works if those costs are recorded per vehicle rather than lost in a shoebox. Your weekly rate should be set knowing a tenth of it is the ATO’s — the pricing framework builds that in.

Is digital signing enough?

Yes — electronic signatures on rental contracts are binding in Australia under the Electronic Transactions Act 1999 (Cth) and mirror state legislation. The requirements are functional, not ceremonial: the method must identify the signer and their intention to be bound, and the parties consent to transacting electronically. An emailed signing link tied to a verified renter, a captured signature, and a stored signed document meets the test. What actually matters operationally is the sequence: the contract is generated from the booking, signed before the keys move, and stored immutably. A car delivered on a handshake with “we’ll sort the paperwork later” is an unpriced excess, an unauthorised deposit and an unprovable damage claim, all at once.

What should you keep out of the contract?

Anything a court would call unfair — the test since the Europcar case is not whether a clause protects you, but whether it goes further than reasonably necessary. The recurring offenders in rental templates:

1. Unlimited or undisclosed liability — renter liable for all damage regardless of fault, or an excess that isn’t actually a ceiling.
2. Open-ended debit authorities — charging whatever you decide, whenever, without itemisation or notice.
3. Unilateral variation — changing the rate or terms mid-term at your discretion.
4. Liability for events outside the renter’s control — the post-return-vandalism example above.
5. Buried terms — the ACL expects plain language, legible and presented clearly; a critical exclusion hidden in schedule fine print may simply not be enforceable.

One inclusion that’s often forgotten: if your cars carry GPS trackers or immobilisers — standard in rideshare fleets — their use must be disclosed in the agreement. That disclosure is also what makes the devices usable when a car doesn’t come back (see the overdue returns playbook).

The bottom line

A compliant Australian rental contract isn’t longer — it’s more specific. A named deposit with written forfeiture rules and no open card authority; a dollar excess (age-banded if you like) frozen at signing; GST-inclusive pricing with a tax invoice behind every payment; a real digital signature before delivery; and nothing in the fine print you’d be embarrassed to read aloud in the Federal Court. Europcar’s $100,000 lesson is that the aggressive template is the expensive one.

This article is general information, not legal advice. Have an Australian commercial lawyer review your contract template before you rely on it.