Asking a past client for a referral feels informal. Once the ask goes out by email or text, it is a commercial electronic message under federal law, with its own consent and unsubscribe rules — rules that are more forgiving than most firms assume, provided the ask goes to the right list.
Key takeaways
A text to a past client saying "if you know anyone who needs a roof, send them my way" reads like a favour, not a marketing campaign — but the moment it is sent electronically to promote the business, it falls under CASL section 6, which sets out the prohibition on sending a commercial electronic message unless the recipient has consented and the message identifies who sent it, gives a way to contact them, and includes an unsubscribe mechanism that stays valid for at least 60 days. None of that changes because the message is short, friendly, or sent from a personal phone rather than a marketing platform.
This is the good news most firms do not realize applies to them: a firm does not need a fresh opt-in to email a past client asking for referrals, because CASL's implied consent rules already cover the relationship. Section 10(9) and (10) of CASL defines an existing business relationship as covering "the purchase or lease of a product, goods, a service, land or an interest or right in land, within the two-year period immediately before the day on which the message was sent," and extends to a written contract that is "currently in existence or expired within" that same period. A bare inquiry, without a completed job, is covered too, but only "within the six-month period immediately before the day on which the message was sent."
In practice, that means a client whose job wrapped fourteen months ago is squarely inside the two-year window for an email or text referral ask — no separate consent needed. A prospect who only requested a quote and never signed anything falls out of coverage after six months, and needs express consent, or a fresh conspicuously-published-address basis, before a referral ask can go to them.
CASL section 11 requires the mechanism to let a recipient opt out "using the same electronic means by which the message was sent, or, if using those means is not practicable, any other electronic means," and the address or link provided has to "remain valid for a minimum of 60 days." Once someone opts out, the sender has to "ensure that effect is given to" the request "without delay, and in any event no later than 10 business days" afterward. A single referral text still needs a working way to say stop — it is not exempt just because it was a one-off.
It is a genuine and easy mistake to assume that because email consent lasts two years, a follow-up phone call to the same past client is covered for the same period. It is not. The CRTC's Unsolicited Telecommunications Rules set their own existing-business-relationship exemption for phone calls under the National DNCL rules, and it runs on a shorter clock than CASL's: 18 months from a purchase, six months from a mere inquiry, measured against the National Do Not Call List rather than against CASL's consent regime at all. A client whose relationship with the firm is comfortably inside CASL's two-year email window can already be outside the phone exemption's 18-month one — treat the two channels as running on genuinely separate clocks, not the same one.
Some firms now route referral and review follow-up through an automated caller rather than a person dialling manually, and it is worth knowing that the CRTC's rules were not written with only human callers in mind. The definition of an ADAD — an automatic dialing-announcing device — under the CRTC's Unsolicited Telecommunications Rules covers "any automatic equipment incorporating the capability of storing or producing telecommunications numbers used alone or in conjunction with other equipment to convey a pre-recorded or synthesized voice message," and that wording reaches a synthesised, AI-generated voice exactly as it reaches an old-fashioned recorded announcement. A telemarketer "shall not initiate...a telemarketing telecommunication via an ADAD unless express consent has been provided by the consumer to receive a telemarketing telecommunication via an ADAD from that telemarketer" — a separate, express consent requirement on top of whatever implied consent already covers a human call or a text.
In practice, that means the implied-consent windows this page covers for email, text, and human phone calls do not automatically extend to an AI voice caller. A past client comfortably inside CASL's two-year window, or even the phone regime's 18-month one, has not thereby consented to being called by a synthesised voice specifically — that consent has to be obtained on its own before an automated caller is used for referral or review follow-up.
CASL does allow messaging an address the recipient has "conspicuously published" without an accompanying statement declining unsolicited messages — a business email listed openly on a company website generally qualifies. Phone numbers are treated differently: the CRTC has stated directly, in its real estate telemarketing guidance that "a person sharing their phone number on a website" does not by itself count as consent to receive a call. A publicly listed email and a publicly listed phone number are not interchangeable consent bases, even when they sit on the same web page.
A worked example
A landscaping firm wraps a job for a client in June 2025. In August 2026 — fourteen months later — the firm sends a short referral-ask text: "thanks again for the work last year, if you know anyone looking for a similar job, we'd appreciate the introduction." Because the transaction falls inside CASL's two-year implied-consent window, no separate opt-in is needed for the text itself, though it still needs sender identification and an unsubscribe option.
A different prospect requested a quote in November 2025 but never signed a contract. By August 2026, that inquiry is nine months old — past CASL's six-month inquiry window — so an email or text referral ask to that contact now needs express consent on file, not implied consent from the old inquiry.
If the landscaping firm instead wanted to phone the June 2025 client rather than text them, the same fourteen-month gap would already be inside the phone-based EBR test's 18-month purchase window too, in this specific case — but a client whose job wrapped 20 months earlier would be covered for an email referral ask under CASL's two-year rule while being outside the phone exemption entirely, which is the gap firms most often miss.
Not on implied consent alone — CASL's existing-business-relationship rule covers a completed transaction for two years from the transaction date, so a job that closed three years ago has fallen outside that window. Express consent, collected separately, would still allow the message.
Yes. CASL section 11 applies to any commercial electronic message, one-off or recurring, and the requirement is a working way to opt out that stays valid for at least 60 days — message frequency does not create an exemption.
Not automatically. The CRTC has stated directly that a phone number displayed on a website is not, by itself, consent to be called, and the number would still need to be checked against the National Do Not Call List and any applicable existing-business-relationship exemption before calling.
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