---
title: "What consent does CASL require for SMS in Canada?"
description: "CASL consent for SMS in Canada: express and implied consent, how long implied consent lasts, required identification and the no-cost unsubscribe within 10 days."
canonical: "https://omnichannels.ai/answers/canada-casl-sms-consent/"
language: "en"
updated: "2026-11-06"
publisher: "BroadNet Technologies"
brand: "OmniChannels.ai"
---

# What consent does CASL require for SMS in Canada?

Canonical: https://omnichannels.ai/answers/canada-casl-sms-consent/
Language: en
Publisher: OmniChannels.ai by BroadNet Technologies

**Short answer:** CASL requires consent, either express or implied, before you send a commercial text in Canada, and the burden of proving it is on you. Express consent does not expire unless withdrawn. Implied consent lasts about 2 years after a purchase or 6 months after an inquiry. Every message must identify the sender and include a no-cost unsubscribe, honoured within 10 business days.

## What types of consent does CASL recognise?

| Type | How it arises | How long it lasts |
|---|---|---|
| Express | The person clearly agrees, for example an unticked box or a keyword text | No expiry, but can be withdrawn at any time |
| Implied: existing business relationship | A purchase or contract with you | Generally 2 years after the event |
| Implied: inquiry or application | The person asked about your products or applied | 6 months |

## What must a commercial text include?

- Identification of the sender and anyone on whose behalf it is sent (section 6).
- A way to contact them; the CRTC suggests business name, mailing address and a phone, email or web address, valid for at least 60 days.
- A no-cost unsubscribe mechanism (section 11), such as replying STOP.
- Unsubscribe requests processed without delay and within 10 business days at the latest.

## How should you record consent?

Treat express consent as the safe base for marketing lists. Record the exact wording shown, date and time, channel and number, and never use a purchased list. Canada uses short codes and long codes rather than registered alphanumeric sender IDs; short codes are applied for at txt.ca. This is an overview, not legal advice, so confirm your program with Canadian counsel.

## Official sources

- [CRTC: CASL frequently asked questions](https://crtc.gc.ca/eng/com500/faq500.htm)
- [CRTC: CASL guidance](https://crtc.gc.ca/eng/com500/guide.htm)
- [Canada's Anti-Spam Legislation, full text](https://laws-lois.justice.gc.ca/eng/acts/e-1.6/fulltext.html)

## Related questions

- https://omnichannels.ai/answers/sms-opt-out-requirements/
- https://omnichannels.ai/answers/transactional-vs-promotional-sms/
- https://omnichannels.ai/answers/whatsapp-marketing-consent/

Updated: 2026-11-06