Postscript Agency
BMO Media runs Postscript SMS marketing for Shopify brands that want every text to earn more than it costs. We build the flows, consent capture and testing that raise revenue per message, and connect Postscript to your email platform so no shopper gets the same nudge twice. The first step is a free audit of your account.
What we do
Why a Postscript specialist, not a generalist
Postscript charges for every message you send, so each text has a cost before it has a return. Generalists schedule SMS like a second email channel, and the numbers argue against that. Across the middle half of Shopify stores, abandoned cart flows earn $3.52 to $10.95 per message while campaigns earn $0.11 to $0.55 (Postscript 2026 SMS Benchmarks, read October 2026).
That gap sets the build order: flows first, and campaigns only to segments that have earned the cost. It also changes what you test. Click rate flatters a text that sends traffic and no orders, so we judge every variant on revenue per message. Quiet hours have to follow the subscriber's clock, not your office's. And because email usually lives in a different tool, suppression has to cross platforms, or a cart abandoner gets an email and a text in the same minute and both claim the sale.
Disciplined sending pays on any platform. For James Michelle, on Klaviyo, SMS campaign revenue rose 111% year over year while campaign volume fell 3%.
What's included
What we do inside Postscript
Account audit: revenue per message, opt-outs per send and capture rate by source, so every fix gets ranked in dollars.
Consent capture: email-first, phone-second popups and checkout opt-ins with consent language stored on every number, because the median subscriber is worth $71.20 in lifetime value (Postscript 2026 SMS Benchmarks); our SMS list growth guide shows the formats.
Flows in revenue order: abandoned checkout, abandoned cart, browse, welcome and post-purchase, each with purchase exits so nobody gets a reminder for something they already bought.
Campaign discipline: sends go to engaged and recent-buyer segments under frequency caps, so you stop paying per message to subscribers who have not clicked in months.
Shared suppression with email: Postscript data synced to Klaviyo or your email platform, so a shopper who just got a cart text skips the matching email and the sale is counted once.
Quiet hours set to the subscriber's local time, with tighter caps in launch and holiday weeks, because an opt-out in your busiest week costs the most.
MMS only where the image sells: every published Postscript plan prices MMS above SMS, so we test text-only against image versions before paying more, as our Postscript pricing breakdown explains.
Carrier deliverability: delivery rate by carrier, link domains and the copy patterns that trip filters, checked monthly so the texts you pay for actually arrive.
Postscript features we lean on
Infinity Testing: AI-written variants tested against a control in both flows and campaigns. We start on the highest-volume flows, where traffic is enough to find a winner, and judge variants on revenue per message.
Postscript AI: the engine that writes those variants in your brand voice. Before it writes anything, we load the voice guide, the claims you cannot make and the compliance wording every text needs.
Shopper: an AI assistant that holds one-to-one text conversations, recommends products and hands off to your support email when it is stuck. We load real shipping, returns and sizing answers, exclude products it should not push and read transcripts weekly.
Postscript Plus: Postscript's own managed service, run by its in-house SMS strategists. If SMS is the only channel you need run, price it against an agency; we earn our place when texts must share a calendar, suppression and reporting with email.
Shopify-native triggers: cart, checkout and order events come straight from Shopify, so flow entries and purchase exits work without extra plumbing.
Switch on first: Infinity Testing on your abandoned cart and checkout flows, because they carry the volume and the margin to learn from.
When Postscript is the right platform
Postscript is one of four SMS setups we run for Shopify brands, and it does not win every time.
Platform | Best fit | Where it falls short |
|---|---|---|
Postscript | Shopify brands that run SMS as its own revenue line, with published per-message pricing and testing built into flows | SMS-first: many stores still run email in Klaviyo, so suppression and attribution span two tools; built around Shopify |
Attentive | Larger brands sending SMS and email together at volume, where identity and AI journeys pay back on a big list | Custom-quoted pricing, and more platform than a small or new list will use |
Klaviyo SMS | Brands already on Klaviyo email that want one profile and one flow builder for both channels | SMS sits inside an email-first tool; brands that run SMS as its own revenue line often want a dedicated SMS platform |
Omnisend | Smaller and growing stores that want email and SMS on one bill with a short setup | Email-first platform with SMS built in; brands that run SMS as its own revenue line may want a dedicated SMS tool |
Choose Postscript when you sell on Shopify and want SMS managed as its own revenue line, with testing built in.
If email runs on Klaviyo and SMS is still small, Klaviyo SMS keeps one profile and one flow builder until texting earns its own platform.
For the bigger head-to-head, read Attentive vs Postscript or see how our Attentive agency work differs.
Results
Results from our SMS programs
Two SMS programs show what we build toward on any platform: more revenue from fewer, better-aimed texts, measured per message.
James Michelle, on Klaviyo: SMS flow revenue rose 235% year over year, and SMS campaign revenue rose 111% while campaign volume fell 3%.
Darc Sport: this program ran on Attentive, not Postscript. We launched SMS while moving email from Mailchimp to Klaviyo. In two months SMS subscribers nearly doubled to 41,000 and SMS revenue rose 29.8%. Campaign texts earned $7.89 per message sent, and revenue from SMS automation sequences rose 80%.
Platforms count attributed revenue over different windows, so we judge each client against its own baseline and a holdout, never against another vendor's benchmark, including Postscript's.
Process
How we work in a Postscript account
Audit, week one: revenue per message for every flow and campaign, popup capture rate against Postscript's 3.6% median (Postscript 2026 SMS Benchmarks), opt-outs per send, delivery rate by carrier, consent records, quiet hours and overlap with email triggers. The audit is yours to keep either way.
Scope: a written plan that ranks each fix by the revenue per message it should add, names an owner for each, and lists what waits until later so nothing competes with the flows. Fixes that cost nothing, like missing purchase exits, ship first.
Build in revenue order: checkout and cart flows first, then browse, welcome and post-purchase, then segmented campaigns. Every rebuilt flow gets Infinity Testing and a randomized holdout, so we can show what the texts added, not just what they sat near in the attribution window.
Report monthly: revenue per message by flow and campaign, incremental revenue against the holdout, net list growth after opt-outs and spend per message, with next month's tests named in advance and the losing variants retired.
Who it's for
Who our Postscript agency works best with
Shopify brands with a working email program, steady traffic and products people come back for: drops, restocks, launches and replenishment. Usually the flows exist but have not been touched in a while, campaigns go to the whole list, and nobody can say what a text earns after it costs. We are a poor fit if you want daily discount blasts, sell outside Shopify, or have too little traffic for texts to earn back their cost yet; in that case we will tell you to grow email first. If your account sounds familiar, book a Postscript audit.
Frequently asked questions