Contractor Wants More Money After Job’s Done: How to Respond

# Contractor Wants More Money After Job’s Done: How to Respond Legally

You agreed a price. The work’s finished. Now the contractor says you owe more.

This happens often enough that you should know how to respond. The contractor emails an invoice for “extras,” claims the scope changed, or points to vague wording in the original quote. Sometimes it’s legitimate. Often it’s not.

Why Contractors Demand Extra Payment After Completion

Contractors ask for more money post-job for several reasons:

• Genuine variations — you requested changes or additions during the job that weren’t in the original scope
• Poor quoting — the contractor underestimated costs and is trying to recover the shortfall
• Scope creep — the job expanded gradually without formal variation approval
• Opportunism — the contractor knows you want the job finalised and hopes you’ll pay to avoid hassle
• Misunderstanding — unclear contract terms or verbal agreements that weren’t documented

The contractor’s reason matters, but what matters more is whether they have a legal entitlement to the extra amount.

What the Law Says: Variations and Contract Terms

Under Australian contract law, you are only obliged to pay what was agreed in the contract. If the contractor wants more, they must prove one of the following:

You Approved a Variation in Writing

Most building and trade contracts include a variation clause requiring any scope changes to be approved in writing before the work is done. If your contract has this clause and you never signed a variation, the contractor cannot unilaterally bill you for extras.

Even if you verbally agreed to a change, many contracts specify that verbal variations are not binding. The contractor should have obtained written approval before proceeding.

You Requested Additional Work

If you asked the contractor to do something outside the original scope — add an extra room, upgrade materials, fix something unrelated — and they did it, you may owe payment even without a formal variation.

However, the contractor still needs to prove:

• You requested the work
• They gave you a price estimate or you should have known it would cost extra
• The work was genuinely outside the original scope

The Original Quote Was Ambiguous

If the contract or quote was vague about what was included, the contractor might argue that certain items were always extra. This is why detailed scopes of work matter. If the contract is genuinely unclear, you may need to negotiate or let a tribunal decide.

Unforeseen Circumstances

Some contracts allow price adjustments for genuinely unforeseeable conditions — asbestos discovered during demolition, structural issues hidden behind walls. These clauses are narrow and must be clearly stated in the contract. The contractor cannot simply claim “it was harder than expected.”

How to Assess Whether You Actually Owe the Money

Before you respond, work through these questions:

Review the original contract or quote

• Is there a variation clause requiring written approval?
• Does the scope clearly describe what was included?
• Are there any clauses about additional costs or unforeseen work?

Check your communications

• Did you request changes via email, text, or in writing?
• Did the contractor warn you that something would cost extra before doing it?
• Did you approve any variations, even informally?

Compare the work done to the scope

• Is the “extra” work genuinely outside what was agreed?
• Or is the contractor trying to charge separately for something that was always part of the job?

Assess the contractor’s evidence

• Have they provided invoices, photos, or records showing the extra work?
• Have they explained why the cost wasn’t included originally?
• Are they claiming a vague “it cost more than expected” or pointing to specific changes?

If the contractor has no written variation, no evidence you approved the change, and the work falls within the original scope, you are on strong legal ground to refuse payment.

How to Respond When a Contractor Demands More Money

Your response depends on whether the claim has any merit.

If the Claim is Clearly Invalid

Send a formal written response stating:

• You dispute the additional amount
• The work was within the agreed scope
• No variation was approved in writing as required by the contract
• You consider the contract completed and will not be making further payment

Keep the tone professional but firm. Do not ignore the demand — silence can be interpreted as acceptance.

If the Claim Has Some Merit

If you did request changes or the scope genuinely expanded, consider:

• Asking the contractor for a detailed breakdown of the extra costs
• Negotiating a reduced amount if the original quote was unclear
• Offering to pay for genuinely additional work while disputing the rest

Document everything. If you agree to pay anything, get a signed settlement agreement stating that the payment is in full and final settlement of all claims.

If the Contractor Threatens Legal Action

The contractor must prove their claim in a tribunal or court, and the burden of proof is on them. If they cannot show a written variation or clear evidence you approved the extra work, they will struggle.

If the amount is under the tribunal threshold in your state (typically $10,000 to $25,000), the dispute would go to the relevant civil or consumer tribunal. For larger amounts, it would go to a court.

Common Contractor Arguments and How to Counter Them

“You verbally agreed to it”

If your contract requires written variations, verbal agreements are not binding. Even without that clause, the contractor must prove the conversation happened and that you understood it would cost extra.

“It was always going to be extra”

If the original quote didn’t specify that certain items were excluded, the contractor cannot later claim they were add-ons. The quote should have been clear from the start.

“I did more work than quoted”

Unless the extra work was requested by you or approved in writing, the contractor cannot unilaterally expand the scope and then bill you for it.

“Industry practice is to charge for this separately”

Industry practice does not override the contract. If the contract says the price is fixed or requires written variations, that is what applies.

What Not to Do

• Do not pay under pressure — paying an invalid claim sets a precedent and makes it harder to dispute later
• Do not ignore the demand — respond in writing, even if only to dispute it
• Do not rely on verbal conversations — put everything in writing from this point forward
• Do not threaten or abuse the contractor — keep all communications professional and factual

When to Get Legal Help

Most contractor payment disputes can be resolved by standing firm on the contract terms. However, consider getting advice from a qualified Australian lawyer if:

• The amount is large (over $10,000)
• The contractor has filed a tribunal claim or court action
• The contract is ambiguous and you need an interpretation
• The contractor has placed a lien on your property or lodged a security of payment claim

For disputes under the tribunal threshold, you can often represent yourself. For larger or more complex matters, legal advice is worth the cost.

How ClaimDone Helps

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Frequently Asked Questions

Can a contractor legally demand more money after the job is finished?

Only if you approved a variation in writing, requested additional work outside the original scope, or the contract allows for price adjustments in specific circumstances. If none of these apply, you are not obliged to pay extra simply because the contractor underquoted or the job was harder than expected.

What if I verbally agreed to changes during the job?

If your contract requires variations to be approved in writing, verbal agreements may not be binding. Even without that clause, the contractor must prove the conversation happened and that you understood it would cost extra. Always get variations in writing to avoid disputes.

Do I have to pay if the contractor threatens to take me to court?

No. The contractor must prove their claim in a tribunal or court, and the burden of proof is on them. If they cannot show a written variation or clear evidence you approved the extra work, their claim is weak. Do not pay under pressure — respond in writing disputing the amount.

What should I include in my response to the contractor?

State clearly that you dispute the additional amount, explain why (no written variation, work was within scope, etc.), reference the relevant contract terms, and confirm you consider the contract completed. Keep the tone professional and factual, and send it in writing.

Can a contractor put a lien on my property for unpaid extras?

In some states, contractors can lodge a security of payment claim or lien if they believe they are owed money. However, they must follow strict procedures and the claim must be valid. If you dispute the amount, you can challenge the claim through the relevant tribunal or adjudication process. Get legal advice if a lien is threatened.