A CASL email signature is not a legal category. Canada’s anti-spam Act regulates commercial electronic messages, and its identification and unsubscribe duties attach to those messages, not to every email a person types. If a message is commercial, the sender must be named, a way to reach them must be shown, and a working unsubscribe mechanism must be included. This is general information, not legal advice, and we read the sources below on 5 October 2026.
We could not read the CRTC’s own FAQ page, because crtc.gc.ca showed us a bot-check page instead of content. So this article rests on the Act and its regulations as published on the Government of Canada’s Justice Laws site, current to 21 September 2026. Nothing here comes from CRTC guidance or enforcement decisions.
CASL email signature: the short version
- The duties apply to a “commercial electronic message”, defined in section 1(2). A plain reply with contact details is not automatically one.
- A commercial message must identify the sender, give contact details and carry an unsubscribe mechanism (section 6(2)).
- The CRTC Regulations list the identity items: business name, mailing address, and a phone number, email address or web address.
- The unsubscribe must be free, use the same electronic means, and be honoured within 10 business days (section 11).
- Consent is a separate duty. No signature line supplies it.
When a CASL email signature becomes part of a commercial message
Section 6(1) of the Act prohibits sending a commercial electronic message to an electronic address unless the recipient has consented, expressly or by implication, and the message meets section 6(2). Section 1(2) defines the term. A message counts if it is reasonable to conclude that one of its purposes is to encourage participation in a commercial activity. The Act names three things to weigh: the content, the hyperlinks to a website or database, and the contact information contained in the message.
That last item is why a CASL email signature draws attention. We read it as saying the contact block is part of what gets assessed, not that a signature alone turns an email commercial. The Act’s examples of commercial purposes include offering to sell a product or service and promoting a person as someone who does so. A promotional banner in a signature points that way. A name, role and phone number do not obviously do so.
The Electronic Commerce Protection Regulations (the Industry Canada set, registered in 2013) take some messages out of section 6. Section 3 says it does not apply to a commercial message sent between employees or representatives of one organization, or of two organizations with a relationship, about the organization’s activities. It also excludes a message sent in response to a request, inquiry or complaint, or otherwise solicited by the recipient. Both fit ordinary one-to-one correspondence, where a CASL email signature carries no unsubscribe line. Neither excuses a bulk campaign.
CASL identification requirements, line by line
The separate Electronic Commerce Protection Regulations (CRTC) set out the prescribed information. Here is how each piece maps to a CASL email signature or footer.
| Requirement | Where it comes from | What it can look like |
|---|---|---|
| The name the sender carries on business under, if different from their own name | CRTC Regulations, section 2(1)(a) | A company line |
| If sent for someone else, that person’s name and a statement of who sends and who it is sent on behalf of | Section 2(1)(b) and (c) | “Sent by X on behalf of Y” |
| A mailing address | Section 2(1)(d) | A postal address line |
| One of: a phone number reaching an agent or voice messaging system, an email address, or a web address | Section 2(1)(d) | A reply-to email or website |
| All of the above, and the unsubscribe, set out clearly and prominently | Section 3(1) | Not in tiny grey type |
| An unsubscribe that can be readily performed | Section 3(2) | One step, no login wall |
| Contact details and unsubscribe address valid for at least 60 days after sending | Act, sections 6(3) and 11(2) | Keep the mailbox after a campaign |
Section 2(2) of the CRTC Regulations allows a fallback. If it is not practicable to put the identity information and unsubscribe mechanism in the message, they may sit on a web page that is readily accessible at no cost, reached through a link set out clearly and prominently in the message. We would treat that as a fallback, since a footer is usually practicable.
The unsubscribe in a CASL email signature or footer
Section 11(1) says the mechanism must let the recipient indicate, at no cost, that they no longer want commercial messages from the sender, or a specified class of them. It must use the same electronic means by which the message was sent. If that is not practicable, another electronic means is allowed. It must also specify an electronic address, or a link to a web page reachable through a browser, to which the request can be sent.
Section 11(3) requires the sender to give effect to the request without delay, and in any event within 10 business days, without any further action from the person. For email, “reply with STOP” fits the same-means wording, and a link to a page fits paragraph (b). An unwatched mailbox meets neither in practice.
A CASL email signature and footer, drawn
Here is a made-up staff signature, then a separate line for campaign mail. They do different jobs. The signature identifies the person and company on every message. The campaign line carries the unsubscribe.
|
Example only. The company, address and person are made up.
For a promotional message, a footer in our own wording could read:
Sent by Maple Harbour Foods Inc., 100 Example Street, Toronto, ON. Questions: hello@mapleharbour.example. To stop receiving commercial email from us, reply to this message with STOP or use https://mapleharbour.example/unsubscribe.
This shows the shape only. It names the sender, gives a mailing address and an email address, and offers an unsubscribe by the same means plus a link. It says nothing about consent, and a lawyer has not checked it.
Consent still sits outside the CASL email signature
A footer cannot create permission. Section 10(9) says implied consent exists only in listed cases. They include an existing business relationship, an address the recipient has conspicuously published with no “no unsolicited messages” statement (where the message is relevant to their business role), and an address the recipient disclosed to the sender on the same terms. Section 10(10) ties an existing business relationship to periods: a purchase within the two years before the message, or an inquiry within the six months before it. Express consent has its own rules in section 10(1).
Section 6(6) lists messages that need no consent, such as a quote the recipient asked for or a message completing a transaction they agreed to. Its wording is narrow: paragraph (1)(a), the consent condition, does not apply to them. It does not say the identification and unsubscribe duties fall away, so ask a lawyer before assuming they do. Section 6(5) also removes messages between people with a family or personal relationship, as the Regulations define it, and messages to a person engaged in a commercial activity that consist solely of an inquiry or application about that activity.
Penalties, and what we did not read
Section 20(4) caps an administrative monetary penalty at $1,000,000 for an individual and $10,000,000 for any other person. Section 20(2) says the purpose of a penalty is to promote compliance and not to punish.
We did not read the CRTC’s guidance, so we cannot say how it treats any particular CASL email signature layout. We did not read Quebec’s French-language rules, which may touch messages to Quebec recipients, or any privacy law. Our bilingual email signature article looks at the language side. For the United States, see CAN-SPAM and your signature, and for the UK, PECR and business email marketing.
Keeping a CASL email signature consistent across a team
If every employee uses the same identity block, the sender name and contact details do not depend on who remembers to type them. emailfooter, a free WordPress plugin made by Ulrea, lets the company admin set the design and a company details line once. Each person adds their own details and follows steps to install it in their mail app. It does not push signatures into mailboxes, it has no click tracking, and it is English only for now. A campaign’s unsubscribe normally belongs to your email marketing tool, not to a personal CASL email signature.
Our page on the address in an email signature covers how to write the mailing address line, and the company email signatures overview covers rollout.
Frequently asked questions
Does a CASL email signature need an unsubscribe link?
Not on every email. Section 6(2) puts the unsubscribe mechanism on commercial electronic messages. A plain one-to-one reply may fall outside the definition or the Regulations’ exclusions, but a promotional banner changes the picture, so ask an adviser.
What are the CASL identification requirements for a footer?
The CRTC Regulations ask for the sending business name, on-behalf-of details if relevant, a mailing address, and a phone number, email address or web address. All must be clear and prominent.
Does a Canada anti-spam law email footer need a mailing address?
For a commercial electronic message, yes. Section 2(1)(d) of the CRTC Regulations lists the mailing address, plus one other contact item. A website address alone does not cover the mailing address.
How long do I have to honour an unsubscribe request?
Section 11(3) says without delay and in any event no later than 10 business days after the request was sent. The address or web page must stay valid for at least 60 days after the message.
Is a CASL email signature different for B2B email?
The Act does not exempt B2B as a class. The Industry Canada Regulations exclude certain messages between organizations that have a relationship and concern their activities, and section 6(5) covers some business inquiries. Read both before relying on either.
Keep reading
- CAN-SPAM and your email signature: what the US rules actually require: A CAN-SPAM email signature guide: the FTC’s requirements mapped to footer lines, and what the guide says, and does not say, about one-to-one business email.
Make every signature in your company match
emailfooter is a free WordPress plugin. You design the signature once, and each person adds their own details and installs it in their mail app. Prefer not to run a website? emailfooter Managed is the same software, hosted for you.