“Pay me what it’s worth!”- an overview of quantum meruit and quantum valebant

Contracts sometimes fail to provide fair compensation for goods or services supplied to another person or company. There may in fact be no contract to enforce to obtain payment. Quantum meruit (Latin for “as much as he deserved”) in the case of the provision of services and quantum valebant (Latin for “as much they were worth”) in the case of provision of goods, may offer a pathway for a party to recover the fair value of works performed or goods supplied.

A claim in quantum meruit and quantum valebant can arise in any industry that supplies goods or services such as professional services, labour, consulting and construction.

Principles regarding quantum meruit and quantum valebant

Quantum meruit and quantum valebant are remedies developed to address scenarios where a party benefits from another’s labour or resources without compensation. It allows a party to recover the “fair value” of the goods supplied or works performed. They may arise in the following scenarios:

1. Where no formal contract exists.
2. Where the contract is void or unenforceable.
3. Where the contract is terminated or rescinded.

Limits on quantum meruit and quantum valebant

Despite its apparent benefits, there are limits to quantum meruit and quantum valebant claims to prevent claimants from obtaining windfalls. Quantum meruit and quantum valebant claims are principally limited in two ways:

1. quantum meruit and quantum valebant claims are limited by the contract price attributable to the relevant work and/or goods (although there may be circumstances where a claim could exceed the contractual price, such as when the other party causes continuous breaches of a contract, causing cost overruns and rendering the contract unprofitable); or
2. if a party has a sufficient claim in contract, it must bring a contractual claim and not a claim in quantum meruit or quantum valebant (e.g. if a provider has reached a contractual milestone, they must claim under the contractual terms for the work covered by that contractual milestone rather than claim under quantum meruit ).

Case illustrations of quantum meruit and quantum valebant

Quantum meruit and quantum valebant originated from 16^th century English jurisprudence. It has evolved over time, and its limitations and use have been shaped by its place amongst other similar causes of action.

It’s most recent material judicial consideration occurred in the 2019 High Court decision of Mann v Peterson (2019) 267 CLR 560.

Despite its age, quantum meruit and quantum valebant remains a relevant consideration today.

The following examples highlight some recent decisions involving quantum meruit:

• Accountancy Practice: Locke v H.C. Loneragan & Company Pty Ltd as trustee for the Loneragan Family Trust t/a Quantum Forensic Solutions [2025] NSWCA 166. In this case, a director of a company engaged a firm of forensic accountants (Quantum Forensic Solutions) to assist with an investigation into alleged spending discrepancies.
  The contract between Mr Locke and Quantum Forensic Solutions related to “Phase-1” works, which were capped at $20,000.00 plus GST.
  Quantum Forensic Solutions completed the “Phase-1” works and Mr Locke continued to provide instructions. Quantum Forensic Solutions issued monthly invoices totalling $219,000.00, of which, Mr Locke paid only $30,000.00.
  Quantum Forensic Solutions brought a claim in quantum meruit for the outstanding invoices.
  Quantum Forensic Solutions succeeded in establishing that the fair value of its work was the balance of the invoices because it had evidence that it had previously communicated its hourly rates to Mr Locke and maintained detailed timesheets justifying invoices for over 1,500 hours of complex accounting work.
• Residential Construction: Thallon Mole Group Pty Ltd v Morton; Morton v Thallon Mole Group Pty Ltd [2023] QCA 250. In this case a residential builder (Thallon Mole Group) made a counterclaim against a homeowner for damages under a construction contract and quantum meruit.
  The quantum meruit portion of the claim related to two alleged variations which arose from agreed changes to the scope of cabinetry works.
  The Court denied Thallon Mole Group’s quantum meruit claim on the basis that it was not satisfied that the owner had given the builder directions to perform the additional works. Minutes of site meetings recorded that the variation was discussed but did not indicate that approval for those variations was given.
• Commercial Construction: Spry Civil Construction Pty Ltd v Aussie-Drain Pty Ltd; Aussie-Drain Pty Ltd v Spry Civil Construction Pty Ltd [2025] SASC 99. In this case, Aussie-Drain Pty Ltd (Aussie-Drain) entered into a lump sum contract with Spry Civil Construction (Spry) to carry out sub-surface drainage at the Murray Bridge Racecourse.
  The contract contained a provision that if rock was encountered, prices would ‘need to be reviewed’. Aussie-Drain carried out 37% of the drainage work and encountered rock. Aussie-Drain entered into discussions with Spry during which Aussie-Drain’s principal asserted that it was ‘not my job anymore’; and all but one of Aussie-Drain’s workers subsequently left the site. Spry then completed the works with the material left on site by Aussie-Drain and with the assistance of the sole Aussie-Drain employee onsite who, at Spry’s request, performed some of the works.
  Aussie-Drain made a claim against Spry for contractual damages and in the alternative, in quantum meruit and quantum valebant for the works and materials supplied.
  The Court found that Aussie-Drain had repudiated the contract. The claim in quantum meruit for the value of the works prior to Aussie-Drain’s repudiation failed because the Court held that a contractual wrongdoer should not get the benefit of the fair value of their works or materials supplied prior to the repudiation.
  However, a portion of the quantum meruit and quantum valebant claim was upheld for the works done by the sole Aussie-Drain employee who remained on site after the repudiation (who performed work at Spry’s request) and for loose materials left onsite that were subsequently used by Spry.

Practical considerations

Quantum meruit and quantum valebant can arise in a wide variety of scenarios. There are many factors that will impact upon the success of a claim including the potential existence of a contract, where a contract exists, its terms, and evidence of the work being requested or approved and its performance.

Legal advice about the possible existence of a quantum meruit or quantum valebant claim for the supply of goods and services should be obtained in the context of disputes involving the existence of a contract, the termination or breach of a contract or where claims are pursued outside the strict terms of a contract.