Canada's Anti-Spam Legislation (CASL), in force since July 2014, is one of the strictest anti-spam laws in the world. It prohibits sending commercial electronic messages (email, text, messaging) without the recipient's consent, subject to exceptions. The maximum administrative penalty is $10 million per violation for a business and $1 million for an individual. The private right of action in the Act, however, was never brought into force. For invoicing, the rule is clear: invoices themselves, sent as part of an existing transaction, aren't subject to the consent requirement, but your newsletters and promotions must comply with CASL.
Express vs implied consent
CASL distinguishes two forms of consent. Express consent: the recipient ticked a box (not pre-ticked) or otherwise actively agreed to receive your messages; it remains valid until withdrawn. Implied consent: for example an existing business relationship, such as a purchase in the last 2 years or an inquiry in the last 6 months. Keep proof of where each consent came from — 4invoices doesn't send marketing campaigns or manage consents.
Clear sender identification
Every commercial message must identify the sender: business name, valid mailing address and a way to reach them (phone, email or web address). Show the same business details on your invoices; in 4invoices, they come from the profile you fill in.
Unsubscribe mechanism within 10 business days
Every commercial message must contain a simple, free unsubscribe mechanism. An unsubscribe request must be honoured no later than 10 business days after it's received. Your marketing email tool must handle these unsubscribes.
What's exempt from CASL
CASL provides several exceptions for legitimate business communication. Messages that facilitate a transaction already agreed to, provide warranty or product recall information, or give factual information about an ongoing account or subscription don't require consent. So you can send an invoice or a payment reminder to your customer without opt-in.
On the other hand, once a message aims to encourage commercial activity — promotion, flash sale, seasonal offer, newsletter, demo invitation — it falls within CASL's scope. The line can be thin: a thank-you email after a purchase that promotes other products is a commercial message. When in doubt, treat it as one.
Partial exceptions apply to registered charities and political parties soliciting donations, and certain messages between businesses with an existing relationship are excluded. When in doubt, the prudent approach is to obtain express consent and keep a record of it.
Frequently asked
I bought an email list from a reputable company. Can I use it?
No, not without the consent of the people on it. Consent must have been given to your business (or validly obtained on its behalf); a purchased list doesn't guarantee that, even if the vendor claims it's compliant. Using purchased lists is among the cases the CRTC regularly sanctions.
My website uses a pre-checked newsletter checkbox. Compliant?
No. Express consent requires a positive action: the box must be empty by default and the recipient must tick it themselves. A pre-checked box isn't valid express consent.
A customer unsubscribes. Can I still send them their invoices?
Yes. Unsubscribing from commercial messages doesn't affect transactional communications (invoices, receipts, payment reminders, account information). You keep sending invoices by email, for example as PDFs from 4invoices, even if the customer unsubscribed from your newsletter.
Send your invoices without worrying about CASL
6 months free, no credit card. Invoices are transactional messages: issue them with the tax rate on each line, in your customer's currency, as PDFs.