A comprehensive guide for Toronto business owners. What constitutes a breach, how Ontario courts assess claims, the remedies available, and the practical steps to take when an agreement falls apart.
By Jonathan Kleiman, Barrister & Solicitor · Updated May 2026
A breach of contract occurs when one party to a legally binding agreement fails to perform their obligations — in whole or in part — without lawful excuse.
The agreement can be written, verbal, or implied from conduct. The breach can be a complete failure to perform, a partial failure, late performance, or performance that does not meet the standard required by the agreement.
Under Ontario law, a valid contract requires four elements: offer, acceptance, consideration (something of value exchanged), and an intention to create legal relations. Once those elements exist, both parties are bound. When one party fails to deliver on their promises, the other party has the right to seek a legal remedy.
If you are a Toronto business owner dealing with a party that has stopped performing, refused to pay, or walked away from an agreement, understanding your rights — and your obligations — is the first step toward resolution.
Ontario courts categorize breaches based on their severity and timing. The type of breach you are dealing with determines your available remedies, your obligations, and the urgency of your response.
A material breach is a failure so significant that it goes to the root of the contract. It deprives the non-breaching party of substantially the entire benefit they were entitled to receive.
When a material breach occurs, the non-breaching party has two options: treat the contract as at an end and sue for damages, or affirm the contract and insist on performance while claiming damages for the breach.
Example: A Toronto business hires a software developer to build a custom inventory system for $80,000. The developer delivers a product that cannot track inventory, process orders, or generate reports — the core functions specified in the contract. This is a material breach. The business can terminate the contract and sue to recover amounts paid plus consequential damages.
A minor breach (also called a partial breach) is a failure that does not destroy the purpose of the contract. The contract remains in effect, and the non-breaching party must continue performing — but they may claim compensation for the specific shortfall.
Example: A supplier delivers 950 of the 1,000 units ordered under a supply agreement. The buyer receives substantially what they contracted for, but is entitled to damages for the 50 missing units. The buyer cannot treat the contract as terminated.
Mischaracterizing a minor breach as a material breach is a common and costly mistake. If you walk away from a contract based on what a court later determines was only a minor breach, you may be found to be the breaching party.
An anticipatory breach occurs when one party clearly communicates — through words or conduct — that they will not perform their obligations before the performance date arrives.
The non-breaching party does not have to wait for the performance deadline to pass. They can treat the contract as breached immediately and pursue remedies, or wait and see whether the other side ultimately performs.
Example: A vendor under a contract to supply materials by October 1 emails the buyer on August 15 stating: "We will not be able to fulfill this order." The buyer can treat this as an anticipatory breach, source materials elsewhere, and sue for any additional costs incurred.
A fundamental breach is a category recognized by Ontario courts where the breach is so severe that it effectively destroys the entire basis of the agreement. In cases of fundamental breach, the court may disregard limitation of liability or exclusion clauses in the contract that would otherwise protect the breaching party.
Whether a breach qualifies as fundamental depends on the circumstances. Ontario courts apply the analysis set out in Tercon Contractors Ltd. v. British Columbia, examining whether the exclusion clause was unconscionable or whether enforcing it would be contrary to public policy.
Contract disputes between Toronto businesses arise in almost every industry. The underlying causes are often predictable — and preventable with proper drafting and early legal advice.
The most common breach of contract claim is simple: one party did the work, the other party did not pay. Non-payment disputes affect every type of business — from freelancers chasing invoices to manufacturers owed six figures by a distributor.
Jonathan handles unpaid invoices and loans for Toronto businesses through demand letters, negotiation, and litigation.
A service provider fails to deliver the work promised, delivers defective work, abandons the project, or exceeds the agreed scope and budget. Alternatively, the client refuses to pay for work completed in good faith.
These disputes often turn on the specificity of the contract. Vague scopes of work, undefined milestones, and missing acceptance criteria are the root cause of most service agreement disputes that end up in court.
A contractor walks off the job, delivers substandard work, demands payment beyond the agreed price, or fails to complete the project on schedule. These disputes are among the most expensive to resolve because the stakes often involve real property and significant remediation costs.
If you're dealing with a contractor dispute, see suing a home contractor in Small Claims Court.
A vendor delivers goods that do not meet contractual specifications, delivers late, or fails to deliver at all. Supply chain disputes can cascade through a business, causing consequential losses that far exceed the value of the original order.
A business partner or shareholder violates the terms of a partnership agreement or shareholders' agreement — whether by competing with the business, misappropriating funds, breaching fiduciary duties, or refusing to honour a buyout provision.
Partnership disputes are among the most complex breach of contract matters because they involve both contractual obligations and equitable duties.
A commercial tenant breaches the lease by failing to pay rent, violating permitted use restrictions, subletting without consent, or abandoning the premises. Alternatively, a landlord breaches by failing to maintain the property or violating quiet enjoyment provisions.
Jonathan represents both landlords and commercial tenants in lease disputes across Toronto.
Disputes arising from the purchase or sale of a business — including breaches of representations and warranties, post-closing adjustments, non-competition covenants, and seller financing defaults — are often high-value and factually complex.
See buying a business lawyer for guidance on protecting yourself before a purchase agreement is signed.
Breaches of employment agreements and independent contractor agreements can involve wrongful termination, unpaid compensation, violation of non-competition or non-solicitation clauses, and misappropriation of confidential information.
Most contract disputes share the same origin: the agreement was too vague, the parties assumed they were aligned, and nobody called a lawyer until the relationship broke down.
To succeed on a breach of contract claim in an Ontario court, the plaintiff must prove four elements on a balance of probabilities:
Ontario courts interpret contracts using the principles established in Sattva Capital Corp. v. Creston Moly Corp. — looking at the text of the agreement in the context of the surrounding circumstances known to both parties at the time of contracting.
The strength of a breach of contract claim depends almost entirely on the quality of the evidence. Courts look for:
The single most valuable piece of advice for anyone involved in a contract dispute: document everything, from the moment you suspect a problem.
Free 30-minute consultation with a Toronto business lawyer.
The fundamental goal of contract damages in Ontario is compensatory — to put the non-breaching party in the position they would have been in had the contract been performed.
Expectation damages represent the benefit the non-breaching party expected to receive from the contract. This is the most common measure of damages in breach of contract claims.
Example: A Toronto business contracted to purchase goods for $40,000 and resell them for $60,000. The seller fails to deliver. The buyer's expectation damages are $20,000 — the profit they would have earned had the contract been performed.
Consequential damages cover foreseeable losses that flow from the breach beyond the direct value of the contract — such as lost business opportunities, additional costs incurred to source alternatives, or penalties imposed by third parties.
To recover consequential damages, the losses must have been reasonably foreseeable to both parties at the time the contract was formed.
Reliance damages compensate the non-breaching party for expenses incurred in reasonable reliance on the contract being performed — such as costs of preparation, hiring, or purchasing materials.
Liquidated damages are a pre-agreed amount specified in the contract for certain types of breach. Ontario courts will enforce liquidated damages clauses if the amount represents a genuine pre-estimate of the anticipated loss — but will strike down clauses that function as penalties.
Ontario law imposes a duty to mitigate. The non-breaching party must take reasonable steps to reduce their losses after a breach occurs. Failure to mitigate can significantly reduce the damages a court will award.
Example: A landlord whose commercial tenant abandons the lease must make reasonable efforts to find a replacement tenant. If the landlord refuses to show the space or rejects reasonable offers, the court may reduce the rent arrears claim to reflect what the landlord could have recovered through mitigation.
Document every mitigation effort. Courts expect to see evidence that you acted reasonably — not that you mitigated perfectly.
Specific performance is a court order requiring the breaching party to fulfill their contractual obligations. It is an equitable remedy, typically reserved for cases where monetary damages would be inadequate — such as disputes involving unique real property, rare goods, or irreplaceable obligations.
In practice, specific performance is most commonly ordered in real estate transactions where the buyer seeks to compel the seller to complete the sale of a specific property.
An injunction is a court order preventing a party from taking specific actions — such as breaching a non-competition clause, disclosing confidential information, or diverting business assets. Injunctions can be obtained on an urgent interim basis where irreparable harm would result from waiting for trial.
Rescission unwinds the contract entirely, returning both parties to their pre-contract positions. It is available where the contract was entered into based on misrepresentation, duress, undue influence, or unconscionability.
The first step in most breach of contract matters is not litigation — it's a formal demand letter. A well-drafted demand letter from a Toronto breach of contract lawyer accomplishes several things at once:
Many contract disputes in Toronto resolve at the demand letter stage. When they do not, the letter establishes the foundation for the claim that follows.
Before proceeding to court, an experienced contract dispute lawyer explores whether the dispute can be resolved through direct negotiation or structured mediation.
Settlement is often faster, less expensive, and less disruptive than litigation. A lawyer who understands the litigation landscape can assess the likely outcome at trial and negotiate a settlement that reflects the realistic value of the claim — without the cost and uncertainty of a full hearing.
That said, settlement only serves your interests if it reflects the strength of your position. Accepting a weak settlement out of convenience can cost more than litigating — and the other side knows it.
When negotiation fails, litigation becomes the path to enforcement. The appropriate court depends on the value of the claim and the complexity of the dispute.
The Ontario Small Claims Court handles contract disputes up to $50,000. The procedures are streamlined, discovery is limited, and hearings are typically completed in a single day. Legal costs are lower, and many litigants are represented by lawyers or paralegals.
Common breach of contract claims in Small Claims Court include unpaid invoices, service disputes, deposit recovery, contractor disputes, and property damage claims.
Contract disputes exceeding $50,000 are heard in the Ontario Superior Court of Justice. Superior Court proceedings involve formal pleadings (statement of claim, statement of defence), documentary and oral discovery, pre-trial conferences, and potentially a multi-day trial.
Superior Court is appropriate for complex commercial disputes, high-value claims, and cases requiring equitable remedies such as specific performance or injunctions.
Many commercial contracts include an arbitration clause requiring the parties to resolve disputes through a private arbitrator rather than the courts. Before filing a claim, always check the dispute resolution provisions of the contract — filing in the wrong forum can result in your claim being stayed or dismissed.
Ontario's Limitations Act, 2002 imposes strict time limits on breach of contract claims:
Once the limitation period expires, the right to sue is extinguished. There are limited exceptions (such as fraud or incapacity), but in the vast majority of cases, missing the deadline means losing the claim permanently.
If you suspect a breach of contract, get legal advice immediately. The limitation period may be running even if you are not yet certain of the full extent of the breach.
Verbal contracts are generally enforceable in Ontario. If the elements of a valid contract are present — offer, acceptance, consideration, and intention — the absence of a written document does not invalidate the agreement.
However, verbal contracts create significant evidentiary challenges. Without a written agreement, proving the specific terms, obligations, timelines, and conditions of the deal becomes a credibility contest. Courts must choose between competing accounts of what was agreed, and the outcome is inherently uncertain.
Certain contracts must be in writing to be enforceable under Ontario's Statute of Frauds — including contracts involving the sale of land, guarantees, and agreements that cannot be performed within one year.
The lesson for Toronto business owners is straightforward: put every agreement in writing. The cost of having a contract lawyer draft a proper agreement is a fraction of the cost of litigating a verbal deal that goes wrong.
The best breach of contract strategy is prevention. Properly drafted contracts reduce the likelihood of a dispute and strengthen your position if one arises.
A Toronto business lawyer can review your standard contracts and identify gaps before they become disputes.
You should speak with a breach of contract lawyer in Toronto as soon as any of the following occur:
Early legal advice is almost always less expensive than late legal advice. A lawyer involved before a dispute escalates can often resolve it at a fraction of the cost of litigation.
Jonathan Kleiman is a breach of contract lawyer in Toronto who represents businesses and individuals in contract disputes across the Greater Toronto Area.
With over 15 years at the Ontario Bar, 400+ matters resolved, and a 4.7-star rating from 224 verified Google reviews, Jonathan brings the experience and track record that Toronto business owners rely on when a contract falls apart.
Call 416-554-1639 or book a free consultation.
A breach of contract occurs when one party to a legally binding agreement fails to perform their obligations without lawful excuse. This includes failure to pay, failure to deliver goods or services, defective performance, or violation of specific contractual terms.
A material breach goes to the root of the contract and entitles the non-breaching party to terminate the agreement and sue for damages. A minor breach is a partial failure where the contract remains in effect but the non-breaching party may claim compensation for the specific shortfall.
Under Ontario's Limitations Act, 2002, the basic limitation period is two years from the date the breach was discovered or ought to have been discovered. There is also an ultimate limitation period of 15 years.
Yes. Verbal contracts are enforceable in Ontario if the essential elements of a contract are present. However, proving the terms of a verbal agreement is significantly more difficult than proving a written contract.
You may recover expectation damages (the benefit you expected), consequential damages (foreseeable losses), reliance damages (expenses incurred in reliance on the contract), and liquidated damages (if specified in the agreement). Punitive damages are rare in contract cases.
In most cases, yes. A demand letter from a lawyer puts the other party on formal notice, establishes a deadline, and resolves many disputes without the need for litigation.
Specific performance is a court order requiring the breaching party to fulfill their contractual obligations. It is typically reserved for cases where monetary damages are inadequate — such as disputes involving unique property.
An anticipatory breach occurs when one party clearly communicates that they will not perform before the performance date arrives. The non-breaching party can treat the contract as breached immediately and pursue remedies.
While not legally required, having a contract dispute lawyer significantly improves outcomes. A lawyer assesses the strength of your claim, drafts effective demand letters, negotiates strategically, and represents you in court.
Small Claims Court handles disputes up to $50,000 with simplified procedures and lower costs. Superior Court handles claims above $50,000 and involves formal pleadings, discovery, and potentially a multi-day trial.
Key evidence includes the signed contract, all communications (emails, texts, letters), invoices and payment records, delivery confirmations, a chronological timeline, records of the breach, proof of damages, and evidence of your mitigation efforts.
Yes. Contracts can be formed verbally or through conduct. However, certain contracts must be in writing under Ontario's Statute of Frauds. For all other agreements, the challenge with unwritten contracts is proving the terms.
If a contract has been breached — or you suspect it will be — the cost of doing nothing is almost always higher than the cost of legal advice.
Bring the contract, the correspondence, and the facts. Jonathan will tell you where you stand, what it will cost, and what the most effective path forward looks like.
Move quickly. Document everything. Get a Toronto breach of contract lawyer involved before the limitation period runs. Free 30-minute consultation.