Contract law is the most misunderstood area this site covers, mostly because the folk version (“it doesn’t count unless it’s signed on paper”) is wrong in both directions. Most agreements are binding without any signature at all once offer, acceptance, consideration, and intention line up; and a signed document can still fail if a key clause is void. Contract law in Canada is largely common law (judge-made and similar across provinces), with statutes stepping in for specific areas like electronic signatures and consumer protection.
What actually makes an agreement binding
| Element | Plain meaning | Where founders slip |
|---|---|---|
| Offer and acceptance | One side proposes, the other agrees to those terms | Counter-offers restart the clock; “we’ll sort details later” can undo agreement |
| Consideration | Each side gives something of value | Free favours and unpaid changes to a deal can be unenforceable |
| Intention | Both sides meant legal consequences | Casual texts can still qualify; family favours usually don’t |
| Certainty | The essential terms are defined | An “agreement to agree” on price or scope often fails |
Writing is usually about proof, not validity: a text thread that shows all four elements can bind, and a formal document missing one of them can fail.
Start with these answers
- The foundation: what makes a contract legally binding in Canada.
- Modern formats: can a text message, email, or emoji create a binding contract or signature.
- Drafting: how to write a contract that actually protects you and what an NDA does and doesn’t do.
- Common business contracts: independent contractor agreements and what to check in a commercial lease before signing.
Mistakes that end up in demand letters
- Relying on “nothing was signed.” Conduct, emails, and part performance can all evidence a binding agreement.
- Skipping the essential terms. Price, scope, and timing left “to be agreed” are the classic seeds of an unenforceable deal, or an enforceable one you didn’t intend.
- Copying clauses across jurisdictions. Contract law travels well between provinces, but statutory overlays (consumer protection, employment standards, electronic commerce) do not.
- Treating an NDA as a magic shield. It binds the counterparty who signed it, on the terms it defines, and nothing more.
Official starting points
Guide last updated August 8, 2026.