If you run a Shopify store, you've almost certainly seen Postscript pitched as the SMS layer for your storefront — cart recovery, welcome flows, "back in stock" alerts, all wired into your product catalog and customer events. For that job, it's a strong product. But "Shopify SMS marketing" and "I need to send compliant text at scale to people who aren't always in my cart" are two different problems, and the second one is where a lot of operators start looking for an alternative.
Full disclosure: I work for ReadySMS, so read the comparison with that in mind. I'll try to earn your trust by being specific about where Postscript is genuinely the better fit before I tell you where we win.
Where Postscript is genuinely strong
Let me not bury this. If your SMS program lives entirely inside Shopify, Postscript is built for exactly that and it shows:
- Native Shopify event triggers. Abandoned cart, browse abandonment, order shipped, back-in-stock — all hooked directly to store events without you wiring anything by hand.
- Catalog-aware messaging. Dynamic product images, links, and discount codes pulled from your store.
- Ecommerce-specific reporting. Revenue-per-message, attribution windows, and the kind of dashboards a DTC marketing team wants.
- Subscriber growth tools tuned for ecommerce — popups, two-tap opt-ins, checkout collection.
If that's the whole job and you're happy with the bill, you may not need an alternative at all. (I'm intentionally not quoting Postscript's pricing here — it changes and varies by plan and volume, so confirm it on their site rather than trusting a blog.)
The reason people go looking is usually one of three things: the per-message or platform cost gets uncomfortable as volume grows, they need SMS that reaches beyond Shopify events, or they want voice and SMS in one place. That's the lane ReadySMS lives in.
Where ReadySMS fits differently
ReadySMS is a thin, transparent layer over carrier infrastructure on registered 10DLC routes. It isn't a Shopify-event engine — it's a send-and-receive platform built for anyone who texts at volume: ecommerce, agencies, SaaS, local businesses, healthcare, nonprofits. The tradeoff is honest and worth stating up front:
- You give up the deep native Shopify catalog triggers and out-of-the-box revenue attribution.
- You get much cheaper registered SMS, a built-in power dialer, done-for-you 10DLC, native GoHighLevel sync, 20 free test sends to try it out, and a $25 credit when you register for 10DLC.
For a store that already runs its CRM, flows, and automation somewhere other than a Shopify-locked SMS app — or one piping events into a tool like GoHighLevel — that's often a better shape.
The cost difference, with actual math
This is where the gap usually shows up. ReadySMS bills per outbound segment plus a flat $0.0045/segment carrier pass-through, itemized separately instead of baked silently into a "per-message" number. (We wrote about why that line item matters in The $0.0045 Line Item Most SMS Providers Bake Into Their Price.)
| Tier | Volume / month | Per segment | All-in (incl. carrier) |
|---|---|---|---|
| Starter | 0–50,000 | $0.0155 | $0.0200 |
| Growth | 50,000–500,000 | $0.0125 | $0.0170 |
| Enterprise | 500,000+ | $0.0028 | $0.0073 |
Worked example. Say you've got 8,000 subscribers and you send a weekly promo plus a recovery flow — roughly 50,000 segments a month once you count multipart messages. A typical promo with a discount code and a link runs past 160 characters, so call it 2 segments each.
On the Starter tier at all-in $0.0200, 50,000 segments = $1,000/month. If you cross into Growth volume at $0.0170 all-in, the next 50,000 run $850. The point isn't the exact figure — it's that the per-segment cost is legible and predictable, and it drops as you grow instead of staying flat. Plug your own numbers into the cost calculator before you trust mine.
One caution: an emoji or any unicode character drops a segment from 160 GSM-7 characters to 70. A 175-character promo with a single emoji becomes 3 segments instead of 2 — a 50% cost jump on every send. Keep emojis out of your high-volume blasts and you save real money.
Compliance: done-for-you 10DLC, not a side quest
Ecommerce SMS lives and dies on deliverability, and deliverability lives on registered A2P 10DLC. Unregistered traffic gets carrier-filtered — your "back in stock" text quietly never arrives. ReadySMS handles the whole registration in-app:
- Brand + campaign registration done inside the platform, roughly ~$10/mo per brand and ~$20/mo per campaign in carrier fees, with approval typically in 4–7 business days.
- Automatic STOP/opt-out handling — an inbound STOP propagates so that contact can't be messaged again across any campaign.
- Quiet-hours enforcement based on the recipient's local time, holding sends outside permitted hours.
- Litigator / DNC scrubbing to screen known TCPA-litigator and DNC numbers before send.
- Consent attestation capture for bulk and API sends, building an audit trail.
None of this makes you lawsuit-proof — compliance is ultimately the sender's responsibility — but it removes the parts people most often skip. If 10DLC is new to you, start with Understanding 10DLC Compliance for E-Commerce Businesses and What is 10DLC.
There's also a standalone TCPA & DNC Litigator Scrub at $0.005 per contact if you bought or inherited a list you don't fully trust. Given that TCPA exposure runs $500–$1,500 per text, scrubbing a 10,000-contact list costs $50 — cheap insurance. The full math is in One TCPA Lawsuit vs Scrubbing Your Whole List.
The dialer Postscript doesn't have
This is a category Postscript simply doesn't play in: outbound voice. ReadySMS bundles a Power Dialer so you can text and call from one platform — useful for high-value carts, win-back calls, or wholesale/B2B follow-up where a text alone won't close it.
- Free — $0/mo, 1 agent, 1 number, 500 minutes/mo included, then $0.06/min.
- Pro — $29/agent/mo, up to 3 agents, $0.05/min.
- Team — $69/agent/mo, unlimited agents, $0.0375/min, with speed-to-lead auto-dial, lead routing, and manager monitoring.
The speed-to-lead piece is the interesting one for ecommerce with a sales motion: a new lead comes in, gets an instant SMS and an auto-dial inside the first five minutes — the window where contact rates are dramatically higher. Pricing for both lives on the pricing page.
Native GoHighLevel sync (if that's your stack)
A lot of stores run their broader marketing in GoHighLevel rather than inside a Shopify-locked app. ReadySMS connects to GHL via OAuth with two-way sync — inbound and outbound messages land in both the ReadySMS inbox and your GHL conversations, mapped per location so agencies keep client accounts isolated. If GHL is where your flows already live, that's a tighter fit than running a separate Shopify-only SMS silo. The setup walkthrough is in the GHL SMS setup guide.
So which should you pick?
Quick gut check:
- Stay on Postscript if your SMS program is entirely Shopify-driven, you lean hard on catalog-aware flows and built-in revenue attribution, and the bill doesn't sting yet.
- Move to ReadySMS if you want cheaper registered SMS as volume climbs, you need to reach contacts beyond Shopify cart events, you run GoHighLevel, you want voice in the same tool, or you want done-for-you 10DLC without a separate console.
You don't have to guess on the part that matters most — cost. Run your real monthly volume through the calculator, and if you want to feel the deliverability and inbox before committing, you get 20 free test sends to your own verified number — plus a $25 credit when you submit 10DLC registration. If your cart-recovery copy needs work in the meantime, Abandoned Cart SMS Templates That Actually Recover Revenue is a good place to steal from.
Test it against your own numbers. That's the only comparison that counts.