Contract Variation Example: How To Change a Contract in Australia

Things change fast in business. Maybe a client asks for extra work, a supplier’s costs increase, or you both agree to extend deadlines. When the deal shifts, your contract needs to shift too - and it’s important to do it the right way so the variation is actually enforceable.

In this guide, we’ll walk through what a contract variation is, when to use it (and when not to), a simple step-by-step process, and practical contract variation examples you can adapt for your business. We’ll also share tips to avoid common traps so your updated terms hold up if there’s a dispute later.

What Is A Contract Variation?

A contract variation is a change to the terms of an existing contract that both parties agree to. It can adjust scope, price, timing, responsibilities, or other clauses. You can record a variation by agreement in writing (often the safest route), sometimes by email, or by a formal deed.

In Australia, a variation must be clear, agreed by the right people, and follow any rules in the original contract about how changes must be made. Many contracts include a “no oral modification” clause (requiring changes to be in writing and signed), or a specific process for change requests. If your contract has one of these, you must follow it or your variation may not stick.

For a deeper primer on the mechanics and pitfalls, it’s worth reading this overview of contract amendments.

When Should You Vary A Contract (And When Not To)?

It’s usually appropriate to vary a contract when:

• You’re adding or removing deliverables (scope changes).
• The price or payment schedule needs to change.
• You’re extending or shortening timeframes or milestones.
• There’s a change to responsibilities, service levels or acceptance criteria.
• You need to update legal clauses (for example, liability, IP, confidentiality) to reflect a new risk profile.

However, a variation isn’t always the right tool. Consider alternatives if:

• The original deal is being replaced entirely. It may be cleaner to terminate and sign a new agreement.
• A party is being swapped out (for example, the customer sells their business). That’s usually a Deed of Novation, not a variation.
• There was never a binding contract to begin with (no valid acceptance or consideration). You may need to start fresh.
• Performance has already finished. You’re likely dealing with a settlement or deed documenting what was actually done, not a variation moving forward.

If you’re unsure which path makes sense, it’s safer to pause and get advice before you make changes informally. In many cases, you can still use a short “amendment letter” or a formal Deed of Variation to keep the paper trail tidy and enforceable.

How To Vary A Contract Safely: Step-By-Step

You can keep variations simple and enforceable by following a clear process.

1) Check The Original Contract’s Change Requirements

Look for clauses titled “Variation”, “Change Control”, “Amendment”, or “No Oral Modification”. Many contracts say variations must be in writing and signed by both parties. Some set a specific process (for example, a written change request and a signed change order).

If your contract mandates a particular method, use that method - don’t rely on casual emails or phone calls.

2) Agree The Essentials In Writing

Make the change easy to understand. Identify exactly what is changing (for example, clause numbers, new wording, revised price or timeline), and from what date it applies. If costs or deadlines change, say how and when.

To reduce ambiguity, be explicit about what is not changing: “Except as set out in this Variation, the Agreement remains unchanged.”

3) Decide The Right Document Type

You have options:

• Short email exchange confirming the change (lower formality, higher risk if your contract requires signed changes).
• Letter of amendment signed by both parties (common for straightforward adjustments).
• Deed of Variation (ideal where you want a formal instrument and to avoid issues with consideration).

Unsure which format suits? This guide on how to legally vary a contract explains when to use a deed versus a simple amendment.

4) Get It Signed By The Right People

Make sure the person signing has authority. For companies, consider execution under the Corporations Act - for example, in line with section 127 (two directors, or a director and company secretary, or a sole director/secretary for a proprietary company). Many variations are also validly signed by an authorised representative if the original contract allows it.

If parties are in different places, you can often sign separate copies. When that’s the plan, add a line confirming the variation may be signed in counterpart.

5) Update Your Files, Invoices And Project Plans

Once signed, circulate the variation and update your CRM, project management tools, invoicing schedule and internal checklists. Operational alignment is just as important as legal alignment.

6) Keep A Variation Log For The Contract

Over time, multiple small variations can create confusion. Keep a simple log noting date, purpose, and where the signed document is stored. If changes become extensive, consider consolidating into a restated agreement for clarity.

Contract Variation Examples You Can Adapt

Below are practical examples across common use cases. Treat these as starting points - always tailor the wording to your contract and situation.

Example 1: Scope Change (Additional Deliverables)

Use when a client asks for extra features or services beyond the original scope.

Variation Wording:

“With effect from 1 November 2025, Schedule 1 (Services) is amended to include the following additional Services: (a) design and build of 3 additional landing pages; and (b) integration of CRM with email platform. The Parties agree the Additional Services will be performed in accordance with the Agreement. Except as varied by this document, the Agreement remains unchanged.”

Pricing Add-On:

“In consideration for the Additional Services, the Fees in clause 6.1 are increased by $4,500 + GST, payable 50% on acceptance of this Variation and 50% on delivery.”

Example 2: Price Adjustment (Supplier Costs Increase)

Use when costs rise and you need to increase fees under a longer-term agreement.

Variation Wording:

“From 1 January 2026, the Fee in clause 5.2 is increased from $2.20 per unit to $2.35 per unit (exclusive of GST). All other terms, including minimum order quantities and payment terms, remain unchanged.”

Example 3: Extension Of Time (Project Delay)

Use when completion or delivery needs more time due to a change in circumstances.

Variation Wording:

“The Milestone Date in Item 4 of the Key Terms is extended from 15 December 2025 to 31 January 2026. The revised timetable in Schedule 2 replaces the prior timetable in full.”

Example 4: Payment Terms (Progress Billing)

Use when you move from a single invoice to staged payments.

Variation Wording:

“Clause 7.3 is deleted and replaced with: ‘The Client will pay the Project Fee in three instalments: 40% on execution of this Variation, 40% upon delivery of the beta site, and 20% on final acceptance.’ Payment due dates and methods in clause 7.6 continue to apply.”

You may also tighten protections by cross-referencing any relevant set-off clauses and late payment terms in your contract.

Example 5: Limitation Of Liability Update (Risk Increases)

Use when the project’s risk profile changes (for example, moving from advisory work to hands-on implementation).

Variation Wording:

“Clause 10.4 (Limitation of Liability) is amended to replace the liability cap with: ‘The Supplier’s aggregate liability arising out of or in connection with the Agreement is limited to an amount equal to 12 months of Fees paid or payable under the Agreement.’”

Be careful when changing liability terms. A balanced and clear limitation of liability clause can reduce disputes while keeping the deal reasonable for both sides.

Example 6: Service Level And Support (SaaS Upgrade)

Use when a customer upgrades a subscription and you promise enhanced support.

Variation Wording:

“Schedule 3 (Support Services) is amended to include Priority Support for 10 named users with 2-hour response time (Business Days), as described in Annexure A. The Subscription Fee in Item 7 of the Key Terms is increased to $2,950 per month + GST from the Variation Effective Date.”

Example 7: Construction Change Order (Materials Substitution)

Use when the specified material isn’t available and you agree on a substitute.

Variation Wording:

“Item 12 (Materials) is amended to replace ‘Brand A 10mm tempered glass’ with ‘Brand B 10mm tempered glass of equivalent specification.’ The Contract Price is reduced by $1,200 + GST. The intended completion date remains unchanged.”

Example 8: Clarifying IP Ownership (Deliverables)

Use when you need to clarify that the client will own deliverables after payment.

Variation Wording:

“Clause 9.2 is amended to add: ‘On payment in full of the applicable Fees, the Intellectual Property Rights in the Deliverables (excluding any Pre-Existing Materials) are assigned to the Client. The Supplier grants the Client a perpetual, royalty-free licence to use the Supplier’s Pre-Existing Materials solely as incorporated in the Deliverables.’”

Example 9: Replacing An Attachment In Full (Updated Statement Of Work)

Use when the best approach is to swap the SOW or schedule entirely.

Variation Wording:

“Schedule 1 (Statement of Work) attached to the Agreement is deleted and replaced with the Schedule 1 attached to this Variation. To the extent of any inconsistency, the new Schedule 1 prevails.”

Example 10: Mutual Housekeeping Variation (Clean-Up And Consolidation)

Use when you’re tidying up multiple small changes.

Variation Wording:

“The Parties agree to consolidate prior variations dated 10 May 2025 and 20 August 2025. The consolidated Fee is $38,000 + GST; the Milestone Dates are as set out in Annexure B; and clause 6.5 (Change Requests) is reinstated in full. Save for the above, the Agreement remains unchanged.”

Do You Need A Deed Of Variation, Amendment Letter Or New Contract?

The right tool depends on what’s changing, how formal you need to be, and what the original contract requires.

• Amendment Letter: Great for a simple, mutual change (for example, extending a date, adding a small deliverable). Reference the original contract, specify the clauses changing, and get both parties to sign. If your contract mandates a specific change process, follow it. A short, signed letter often sits alongside your main Contract Amendment template.
• Deed Of Variation: Use when you want higher formality or you don’t want to rely on consideration for the change. A deed is a formal instrument with its own execution requirements and can be the safest option for material changes. You can prepare a tailored Deed of Variation to avoid ambiguity.
• New Contract: If the commercial deal has substantially changed, starting fresh can be cleaner than stacking many variations. It also helps you incorporate everything you’ve learned since the original deal.
• Novation (New Party): If a party is being replaced, vary with care - that’s usually a Deed of Novation, not a variation. Novation swaps a party and transfers rights and obligations to the incoming party.

Whichever route you take, ensure it’s signed properly (for companies, consider execution under section 127), and include an authority statement if an authorised representative signs on behalf of a party.

What About Updating Your Standard Terms?

If you’re changing terms that you use across many customers (like payment windows or service levels), update your master agreement or online terms so future deals start with the improved position. Many businesses keep their Terms of Trade current and then issue short variations (or change orders) as needed for individual projects.

Helpful Signing Tips

• Include a line stating the variation can be signed in counterpart if you expect separate copies.
• Reference the full legal name and ACN/ABN of each party to avoid confusion.
• Attach any replaced schedules in full and label them clearly.
• State “Except as varied, the Agreement remains unchanged.” to prevent accidental changes.

Quick Email-Style Confirmation (Lower Formality)

Sometimes, you’ll want a quick email confirmation followed by a formal document:

“Hi Alex - Confirming we’ll add two extra training sessions in November at a fixed fee of $1,200 + GST, payable with the final invoice. All other terms remain unchanged. We’ll countersign a short variation this week.”

This approach documents intent and timing, but you should still follow up with a signed variation if your contract requires it.

Key Takeaways

• A contract variation changes agreed terms like scope, fees or timelines - but it must follow the original contract’s change process to be enforceable.
• Use a simple amendment letter for straightforward updates, a Deed of Variation for material or sensitive changes, and a new contract if the deal has fundamentally shifted. Use a Deed of Novation when a party is being replaced.
• Make the changes crystal clear: specify what’s changing, when it takes effect, and confirm that everything else stays the same.
• Get the variation signed by the right people. For companies, consider execution under section 127 and allow signing in counterparts if needed.
• Keep your standard terms up to date, and log variations so your team invoices and delivers according to the new deal.
• If risk exposure changes, revisit key protections like payment terms, set-off rights and your limitation of liability to keep the contract balanced.

If you’d like a consultation about varying a contract for your small business, you can reach us at 1800 730 617 or team@sprintlaw.com.au for a free, no-obligations chat.