The pitch for SMS is that open rates are enormous compared with email. That is true and it is the wrong thing to lead with, because open rate is not a cost and SMS has one.
The economics are not comparable
Email is close to free at the margin. Sending to another ten thousand people costs you approximately nothing, which is why a mediocre email campaign is still usually profitable.
SMS is priced per message. Every send is a real cost, so a campaign that would have been quietly break-even as an email is a loss as a text. This single difference should decide most of what you do: SMS has to be reserved for messages worth paying to deliver, and most of what stores send is not.
The consent rules are also not comparable
Email marketing consent is relatively forgiving. SMS is not, and in the United States it sits under rules with statutory damages per message, which is the kind of exposure that ends small businesses rather than annoying them.
Practically: you need explicit consent to text, collected separately from email consent, and a pre-checked box or a bundled "sign up for updates" does not qualify. If your popup collects a phone number as part of an email signup, you probably do not have the consent you think you have.
We are not lawyers and this is not legal advice. It is a reason to get the consent flow right before the campaign calendar, rather than after.
What SMS is genuinely good at
Three things, all of which share a property: they are time-sensitive and short.
- Abandoned checkout, as a second touch. Not instead of the email. After it, for the people the email did not recover.
- Shipping and delivery updates. The messages customers actually want, and the ones that reduce support tickets rather than creating them.
- Genuine deadlines. A sale that really ends tonight, a restock of something that really sells out. Manufactured urgency works once and then trains people to ignore you.
What it is bad at
Anything that needs more than a sentence, anything with a considered decision behind it, and anything you would send weekly. A newsletter by text is a contradiction.
The specific failure mode worth understanding is that an SMS unsubscribe is close to permanent. Email has a middle ground, where someone stops opening but stays on the list and might come back for the right subject line. There is no equivalent for SMS: people reply STOP and they are gone, and you paid for the message that made them do it.
The order we would build it in
Email first, completely, including the four flows that actually earn. Then SMS as a narrow layer on top: transactional and delivery messages first, then a checkout recovery text as a later step in an existing flow.
Campaign SMS, the broadcast kind, comes last if it comes at all. Most of the stores we run do not send it, and their SMS programmes are profitable specifically because of that.
One number worth working out first
Take your per-message cost, multiply by your list size, and compare it against the average order value times a realistic conversion rate for a broadcast. Do that arithmetic before you build the programme, not after the first invoice.
For a lot of small stores the answer is that SMS pays for itself on checkout recovery and loses money on everything else. That is a perfectly good outcome. It just is not the one the platform demo shows you.
Our email and SMS service covers both channels, and a fair amount of the work is deciding which messages do not need to be texts.
