The rule: consent first, then three things in every message
You may send a commercial text or email to a Canadian address only with consent, and only if the message identifies you and lets the person unsubscribe.
"It is prohibited to send or cause or permit to be sent to an electronic address a commercial electronic message unless (a) the person to whom the message is sent has consented to receiving it, whether the consent is express or implied; and (b) the message complies with subsection (2)." (CASL, s. 6(1))
"Commercial" is broad: any message whose purpose, or one of its purposes, is to encourage someone to buy, including one that promotes you (CASL, s. 1(2)). A follow-up that says "still need that furnace replaced? Book here" counts.
CASL implied consent: how long each kind lasts
| How you got the contact | Consent | How long it lasts |
|---|---|---|
| They asked you a question or for a quote (an inquiry) | Implied | 6 months from the inquiry (s. 10(10)(e)) |
| They bought or hired you | Implied | 2 years from the purchase (s. 10(10)(a)) |
| They have a written contract with you | Implied | While it runs, and 2 years after it ends (s. 10(10)(d)) |
| They published a business email with no "no solicitations" note | Implied | Only for messages relevant to their job (s. 10(9)(b)) |
| They said yes, out loud or in writing | Express | Until they withdraw it |
The government's plain-language guide puts the time limits this way:
"Their implied consent may be valid for up to 2 years—or just 6 months in the case of inquiries or applications." (ISED: Getting consent to send email)
Does CASL consent expire?
Implied consent does: the clock runs from the last purchase or inquiry before each message (s. 10(10)). A new purchase or a new question starts a new period. Express consent does not expire:
"Express consent means someone has agreed (verbally or in writing) to receive a commercial electronic message from you. There is no time limit unless the recipient withdraws his or her consent." (ISED)
Ask for express consent while implied consent is still valid. An email or text asking for consent is itself a commercial message (CASL, s. 1(3)), so once implied consent runs out you can't send the request either.
The request, spoken or written, must state what the consent is for, your business name, your mailing address plus a phone number, email or website, and that they can withdraw at any time (s. 10(1); CRTC regulations, s. 4). For example: "Yes, text me reminders and offers from Smith Heating, 12 Main St, Calgary, 403-555-0100. Reply STOP any time."
Do texts count? Yes
"CASL is technology neutral. You must obtain consent to send commercial electronic messages, including text messages." (ISED: Texting for good client relations)
A live two-way phone call is outside this section of CASL, and so is a voice recording sent to a phone (s. 6(8)).
Replying to a new lead: what needs no consent
A message that only gives a quote or estimate the person asked for needs no consent, and neither does one that only confirms a deal they already agreed to (s. 6(6)(a)–(b)). It still must identify you and carry an unsubscribe (s. 6(1)(b)). Add a promotion to that quote and the exemption no longer fits; you're back on the inquiry's 6-month implied consent.
What every commercial text or email must include
- Your business name, and the name of anyone you send for (ISED; s. 6(2)).
- A mailing address, plus a phone number, email or website (ISED).
- Contact details that work for at least 60 days after you send (s. 6(3)).
- An unsubscribe that costs nothing and uses the same channel, such as replying STOP to a text (s. 11(1)).
- Unsubscribes honoured within 10 business days (s. 11(3)).
In a text, if it isn't practical to fit all of this, the contact details and unsubscribe can sit on a web page reached by a clear link in the message (CRTC regulations, s. 2(2)).
Who has to prove consent, and the penalty
You do.
"A person who alleges that they have consent to do an act that would otherwise be prohibited under any of sections 6 to 8 has the onus of proving it." (CASL, s. 13)
Keep, for each contact: the date, how you got the address (form, purchase, verbal yes), and the exact wording they agreed to. The maximum penalty per violation is $1,000,000 for an individual and $10,000,000 for a business (s. 20(4)).
US business with Canadian leads?
CASL applies when a computer system in Canada is used to send or access the message (s. 12(1)), so texting a lead in Canada brings you under it. US email law works the other way round: CAN-SPAM requires no prior consent, but you must offer an opt-out and honour it within 10 business days (FTC). US texts follow different consent rules (see missed-call text back).
Example
A web-form lead
A homeowner in Calgary asks for a water heater quote on March 1. The quote by email needs no consent. Follow-up offers are fine until about September 1. If she hasn't hired you or said yes to messages by then, stop.
A past customer
A client paid a CAD 2,000 invoice in April 2025. You may send your newsletter until April 2027. A new job in 2026 restarts the 2 years.
A sign-up sheet
At a home show, 40 people tick "Yes, send me offers from Smith Roofing" and write their email. The sheet shows the company's address and phone and says they can unsubscribe any time. That's express consent: valid until each one unsubscribes. Keep the sheet.
Different for you?
- Texting leads in the US: missed-call text back and consent.
- How fast to answer a new lead: speed to lead.
- Texting customers to ask for reviews: asking for reviews rules.
- Following up every lead without breaking these rules: Conversion agent.