A customer hands you their mobile number at checkout. Small thing. They tick a box, finish the order, get on with their day. What they’ve actually done is give you a key to the most personal screen they own, the one that sits on the pillow at night and buzzes in the middle of a meeting. An inbox is a corridor anyone can post a letter into. A phone number is somebody’s front room.
Most founders treat the two the same way. They send the same message down both pipes, or they pick one and let the other gather dust. Email because it’s cheap and familiar. SMS because a competitor started doing it and the open rates looked wild.
Run on either channel alone and you’re leaving money and goodwill on the table. Put them together, and with a bit of thought about which message goes where, each one covers for the other’s weak spots.
That’s omnichannel marketing. The right message in the right place, and not one buzz more than you’ve earned.
Short on time? Here are the key takeaways
- Email and SMS do different jobs: email carries the story and the detail, SMS carries the thing that expires.
- A phone number is a privilege: it’s the channel you deliberately underuse, not the one you squeeze for volume.
- Sequence beats blast: inside an automation the two channels work best in order, one picking up where the other left off.
- Consent and timing are part of the product: a badly timed text costs you more than a missed sale.
- One platform keeps the sequence honest: email and SMS built in the same place stop the two channels from talking over each other.
One channel is never the whole story
Email is where you get room to breathe. You can tell a launch story, show the product in context, segment by what someone bought last time, and run the whole thing for next to nothing. The trouble is it waits. Your campaign lands in an inbox that already has forty other unread things in it, and it sits there until the person decides to look, which might be tonight, might be never.
SMS has the opposite shape. It gets opened in minutes, usually seconds, and it cuts straight through the noise. But you’ve got a line and a half to work with, no space to explain yourself, and every send costs real money. Lean on it too hard and you go from welcome to irritating faster than you’d think.
Neither one is the answer on its own. The reason to run both is that the thing email is bad at is the exact thing SMS is good at, and the other way round.
Which message belongs in which room
So how do you decide which channel a message goes to? Ask one question. Does it expire?
If it keeps, send an email. The new collection, the founder’s note, the how-to that makes someone a better customer, the slow nurture that warms a cold list up over a fortnight. None of that is hurt by landing an hour late, and all of it wants room to be read properly.
If it’s on a clock, that’s SMS. A flash sale that ends at midnight. The item someone asked to be told about the moment it came back. The cart they walked away from twenty minutes ago while the intent is still warm. Those messages lose their whole value if they arrive the next morning, and they’re short by nature, which is exactly what the channel is built for.
Get this split right and the two channels stop competing for the same job. Email becomes the place people go to read about you. SMS becomes the tap on the shoulder that only happens when something genuinely can’t wait.
Run them in sequence, not in parallel
The real payoff shows up in your automations, and the mistake I see most is firing both channels at once. Same moment, same trigger, email and text landing together. All that does is use two messages to do one message’s work.
Stagger them instead.
Take the welcome flow. Email goes first, because a new subscriber deserves the proper introduction: who you are, what you sell, the code if you’re offering one. Then, a day or two on, if they haven’t bought, a single short text that nudges them back. Two channels, two moments, one job each.
Abandoned cart runs the same shape. The email does the heavy lifting first, showing the items they left and giving them an easy way back in. If the cart’s still sitting there a few hours later, a brief text closes the gap while they might still care. Back-in-stock is the one place I’d let SMS lead outright, because the person literally asked to be told the second it happened, and a text is the fastest way to honour that. Shipping updates split neatly too: a quick “it’s on its way” by text for the hit of reassurance, the full tracking detail sitting in an email for when they want it.
Then there’s BFCM, the one stretch of the year where the cadence lifts for everyone. Email carries the campaign, the build-up, the offers, the story of the sale. SMS gets held back for the genuinely time-critical beats only: doors open, and the last few hours before they close. If you’re going to earn a few extra texts from people, that’s the week the goodwill is there to spend.
This is the point where having email and SMS in the same tool stops being a nice-to-have. Omnisend builds both channels, plus web push, into one automation view, so a welcome or an abandoned-cart flow can hand off from email to text inside a single workflow instead of you wiring two platforms together and hoping they stay in step. The segments you’ve built from purchase and browsing behaviour feed both channels from the same place, which is what keeps the sequence coherent rather than two tools guessing at each other.
Start with two flows, not ten
That list can feel like a lot, and trying to build all of it at once is how founders end up with nothing finished. So start with the two that pay for themselves fastest: the welcome and the abandoned cart.
Welcome, because it catches people at their most interested, the moment they’ve just signed up or bought, and sets the tone for every message that follows. Abandoned cart, because the money is already halfway out of the wallet, and a well-timed nudge recovers a real slice of it.
Build both as an email with a single SMS backup, then leave them running for a few weeks before you touch anything else. Once they’re earning, add back-in-stock next. The rest can wait until these two are humming.
The channel you choose not to abuse
Most brands should send far fewer texts than their plan allows.
Email forgives frequency. An extra campaign in a crowded inbox is easy to ignore, and nobody resents you much for it. A phone is different. A text that arrives at 11pm, or a third one in a week when two would have done, doesn’t just get deleted. It gets the person reaching for the opt-out, and once they’re gone from SMS you’ve lost the one channel they’ll actually see in time to matter.
So treat consent as the real thing it is. Make the opt-in explicit, keep the opt-out one word away, and mind the clock in your customer’s timezone, not yours. Honour quiet hours. Keep the list to people who genuinely said yes, and let the ones who go quiet go quiet. The restraint is the strategy. A smaller SMS list that still trusts you is worth far more than a big one that’s learned to dread the buzz.
You’ve been let into the front room. Behave like a guest and you get invited back. Overstay and you get shown the door.
Final Thoughts
Done well, omnichannel is a quiet discipline: knowing which message belongs in the inbox and which one earns a place on the lock screen, then letting the two hand off cleanly so neither is doing a job it’s bad at. It was never about sending more. Get that rhythm right and the same customer who skims your emails will act on your texts, because you’ve only ever texted them when it counted.
That’s where Omnisend comes in. It runs email, SMS and push from one platform, with pre-built automations like welcome and abandoned cart that let a flow move from email to text in a single sequence, and behaviour-based segments that keep both channels pointed at the right people. Foundr readers also get 50% off their first three months, just use code FOUNDR50 when you sign up and start sending the two channels as one play instead of two.
P.S. BFCM is only a few weeks out, and there’s still time to get ahead of it. Sorting your email and SMS flows now beats scrambling once the rush hits, and a quiet week before it all kicks off is the cheapest time to get the sequence right.
