A demand letter is a formal written notice that you are owed something — money, the performance of an obligation, or the cessation of a specific conduct — and that you intend to pursue legal remedies if your demand is not met. In Ontario, demand letters are used in a wide range of disputes: unpaid invoices, contract breaches, security deposit disputes, property damage claims, and more. While a demand letter has no formal legal requirements to be "valid," writing one effectively requires understanding the legal landscape in which it operates.

The Purpose of a Demand Letter

Before drafting, it helps to be clear on what you are trying to achieve. A demand letter serves several practical purposes:

Ontario's Limitations Act: The 2-Year Clock

One of the most important legal considerations when sending (or receiving) a demand letter is the Limitations Act, 2002. In Ontario, most civil claims must be brought within 2 years of the day the claim was "discovered" — the day you first knew, or ought reasonably to have known, that you had a potential claim, who is responsible, and that a legal proceeding would be an appropriate remedy.

Critical Warning: Sending a demand letter does not extend or pause the 2-year limitation period. If the deadline is approaching, do not spend time sending letters — file a claim in court (or with the appropriate tribunal) to preserve your rights. You can always negotiate after you have commenced proceedings.

There is also an absolute 15-year limitation period in Ontario — regardless of when you discover the claim, you cannot sue after 15 years from the act that gave rise to the claim. In practice, the 2-year period is far more relevant.

Essential Content of an Effective Demand Letter

While there is no prescribed form for a demand letter in Ontario, an effective letter should include:

  1. Your full name and contact information (or your lawyer's, if represented).
  2. The recipient's full name and address — accuracy matters, particularly if you proceed to court and need to prove service.
  3. A clear statement of the facts — what happened, when, and why it gives rise to your claim. Be accurate and factual; avoid emotional language.
  4. The legal basis for your claim — breach of contract, negligence, unjust enrichment, etc. (you do not need to cite specific cases, but clarity about what legal right you are asserting is helpful).
  5. A specific and quantified demand — the exact dollar amount you are claiming, or the specific action you are requesting, with a clear calculation or explanation.
  6. A reasonable deadline for response — typically 10 to 30 days, depending on the complexity of the matter.
  7. The consequences of non-compliance — a clear statement that you will commence legal proceedings without further notice if the demand is not satisfied.
Tip: Always send the demand letter by a method that creates a record of delivery — registered mail (with the Canada Post confirmation slip), email with a read receipt, or courier with tracking. If the matter proceeds to court, you want to be able to prove the letter was received.

Tone and Language: Professional, Not Emotional

The tone of your demand letter matters significantly. Courts and opposing parties take professionally written, factual demand letters more seriously than angry, emotional rants. Key tone guidelines:

Small Claims vs. Superior Court: Know Your Forum

In Ontario, the choice of court depends on the amount of your claim:

Mention the appropriate court in your demand letter. A credible threat of litigation requires that the threat be realistic — a claim for $5,000 in Superior Court is harder to take seriously than one in Small Claims Court where the process is designed for exactly that amount.

When to Involve a Lawyer

Not every demand letter requires a lawyer, but legal involvement is advisable in several situations:

A lawyer-authored demand letter on a law firm letterhead often resolves disputes more quickly than a self-drafted letter — the implicit message is that the sender is prepared and serious about litigation.