On December 31, 2025, Yotpo shut down SMSBump — leaving roughly 25,000 Shopify merchants without an SMS platform and five months to migrate their lists, flows, and phone numbers. The company pointed departing merchants toward Attentive and Omnisend. Neither is a simple or affordable fit for a $10k/month store.
That shutdown is a useful forcing function for a decision most small Shopify stores have been deferring: which SMS app actually makes sense at under $30k/month?
For most stores already running Klaviyo email, Klaviyo SMS is the rational default — not because it’s the most capable SMS tool, but because it’s already in the stack and adding SMS costs as little as $15/month extra. The exception: if cart recovery is a specifically targeted revenue line, TxtCart’s Starter tier ($0/month plus 15% of attributed revenue) removes all financial risk from the test. Postscript is the deepest Shopify-native SMS platform available, but its cost structure is hard to justify under $20k/month unless SMS is being built as a primary channel.
Pair SMS with a solid helpdesk app for your Shopify store — SMS generates inbound customer replies that need somewhere to land.
Why This Decision Matters Now: The SMSBump Shutdown
SMSBump was acquired by Yotpo in January 2020. For five years it was one of the most widely used Shopify SMS tools among mid-size stores that wanted a dedicated platform without enterprise pricing.
On August 5, 2025, Yotpo CEO Tomer Tagrin announced the company was exiting email and SMS entirely — roughly 200 layoffs, approximately one-third of the workforce — to refocus on reviews and loyalty products (confirmed by Spam Resource). Services ended December 31, 2025. Approximately 25,000 merchants were affected, per Dondy.
Five months is enough time to migrate a list. It is not a comfortable runway. The tools Yotpo pointed merchants toward sit at opposite ends of the complexity spectrum: Attentive is an enterprise-grade platform; Omnisend is a solid mid-market email-plus-SMS option but not a surgical replacement for stores that used SMSBump for Shopify-native segmentation.
The broader lesson isn’t “avoid acquired tools.” It’s that acquired tools optimize for the parent company’s roadmap, not the original customer base. SMSBump’s small-store focus wasn’t Yotpo’s priority after the acquisition — and ultimately wasn’t worth keeping at all. Standalone revenue model matters when choosing a platform to build a list on.
Before Buying Any SMS App: The 10DLC Compliance Cost
Every SMS platform markets an entry cost. None leads with the compliance cost. That gap is worth understanding before signing up for anything.
US 10DLC (10-Digit Long Code) requires brand registration with The Campaign Registry before sending any commercial Application-to-Person (A2P) SMS. Since February 1, 2025, carriers block 100% of unregistered A2P messages — not throttle, block entirely. Unregistered SMS does not deliver.
Brand registration is a one-time fee: approximately $4 for sole proprietors, $48 or more for standard business entities, with possible secondary vetting for certain business types. Each use-case or campaign type may require its own campaign registration on top of brand registration, plus ongoing monthly carrier fees that flow through regardless of which SMS platform is used.
All three tools covered here walk merchants through registration during setup. The actual fees and approval wait — typically one to two weeks — are real regardless of platform.
Budget 1-2 weeks between account creation and first compliant send. Budget $4-$48 minimum for registration plus recurring carrier passthrough fees. Every tool markets zero-cost entry. Compliance isn’t free; it’s just invisible until the first bill.
Comparison at a Glance
| Tool | Best for | Starting cost | Per-message cost | Revenue share | Shopify-only | Email included |
|---|---|---|---|---|---|---|
| Postscript | Dedicated SMS programs, deep Shopify segmentation | Free (pay-per-message) then $25/mo Growth | $0.015/SMS + approx. $0.004 carrier | None | Yes (US/CA only) | No |
| Klaviyo SMS | Stores already on Klaviyo email | Approx. $15/mo add-on to email plan | Approx. $0.009/US credit | None | No (multi-platform) | Yes |
| TxtCart | Cart recovery, performance-first | $0/mo + 15% attributed revenue | Included in rev-share | 15% / 7.5% / 2.5% | Yes | No |
Pricing sourced from public product pages as of July 2026; verify at source before purchasing, as SMS platform pricing changes frequently.
Postscript: The SMS Specialist Built for Shopify
What It Does
Postscript is Shopify-native, US and Canada only, SMS-only — no email product. That specialization is both the value proposition and the constraint.
The platform offers 45-plus segmentation filters pulling directly from live Shopify data and over 65 automation triggers. AI Infinity Testing runs multi-variant tests across message variants automatically. For stores that want to build a real SMS program — keyword opt-ins, conversational flows, segmented campaigns by purchase history, browse behavior, predictive LTV — Postscript has the depth to do it.
Real Pricing Math
The “free” plan isn’t zero-cost. Every send on the free/Starter tier costs $0.015/SMS plus approximately $0.00418 in carrier passthrough fees — roughly $0.019 per message all-in. At 1,000 sends per month that’s approximately $19. At 5,000 sends it’s approximately $95 with no platform fee. The Growth plan at $25/month offers lower per-message rates; the breakeven depends on send volume.
Postscript reports 34x average ROI across its merchant base (vendor-reported figure; verify at source). The caveat is attribution: native Postscript attribution uses a broad click window that can overcount revenue attributed to SMS. Pairing with a third-party attribution tool to measure SMS ROI is worth the overhead before scaling a program.
Where It Makes Sense — and Doesn’t
On r/shopify, one store owner described Postscript for high-intent cart abandons: “worked way better than email alone… felt less like spam and more like a nudge.” That captures the genuine upside — SMS for time-sensitive, high-intent moments converts differently than email.
Real operational gotchas exist. G2 reviews include a report of approximately $1,800 in unused credits accumulated over nine months due to credit rollover terms. Community sentiment also notes that Postscript support has shifted toward AI-driven responses with reduced human availability.
The “no monthly fee” framing is largely marketing at meaningful send volumes. At around 3,000 or more sends per month, per-message costs exceed what a $25/month Growth plan would cost with lower per-message rates. Stores also pay for SMS-only without the email unification Klaviyo provides.
Postscript is correctly priced for the store size it’s built to serve. The problem is that it gets recommended to stores that haven’t yet validated SMS as a channel and can’t extract value that justifies the per-message cost at low volumes.
Best for: Stores at $20k-plus per month, committed to SMS as a primary channel, that need deep Shopify segmentation, conversational flows, and keyword programs.
Klaviyo SMS: The Case for Keeping It All in One Platform
How Pricing Works
Klaviyo SMS is not a standalone product — it’s an add-on to a Klaviyo email plan. There is no SMS-only Klaviyo path. For stores already paying for Klaviyo email, adding SMS means upgrading to the Email + Mobile tier, which adds approximately $15/month at entry-level (1,001-1,500 profiles: $45/month email → $60/month email plus SMS, with 1,250 SMS credits included). Credits cost approximately $0.009 per US SMS beyond the included allocation. The free plan includes 150 SMS credits.
For base email cost context, see Klaviyo’s email plans for small Shopify stores.
The Email-Plus-SMS Unified Advantage
The case for Klaviyo SMS isn’t that it’s the best SMS tool. It’s that unified data has compounding value.
One profile. One flow. One attribution model. A cart-abandon sequence can trigger an email at one hour and an SMS at three hours from the same automation — no syncing two separate platforms. Purchase history, browse behavior, and predictive LTV all live in the same segments, feeding both channels. There’s no double-counted revenue attribution between an email tool and an SMS tool running parallel campaigns on the same list.
One store owner on r/shopify captured the core appeal: “Klaviyo is expensive but the segmentation is worth it. Tried cheaper options and always came back.” That sentiment tends to apply to email — but the same unified-data argument extends to SMS as an add-on.
Is There an SMS-Only Path?
No. Klaviyo SMS requires an active email plan. For stores not already on Klaviyo email, this means paying for both products — and at that point the economics shift compared to a dedicated SMS tool.
Community evidence on r/shopify is genuinely mixed about SMS lift under approximately 5,000 contacts. One store owner with a substantial email list reported: “SMS does zero for us,” citing list frequency as a more important driver than channel. SMS lift is real in many categories but not automatic.
Klaviyo SMS is the rational default for stores already on the email plan. Adding SMS for $15/month to a tool already understood and paid for is a lower-risk test than onboarding an entirely new platform. “Rational default” is not the same as “will definitely work” — at 500 orders per month, SMS lift remains speculative and category-dependent.
Best for: Stores already on Klaviyo email that want to add SMS without adding a second platform, tool, or attribution problem.
TxtCart: The Performance Model That Changes the Risk Math
How Revenue Share Works
TxtCart is a cart-recovery SMS tool, not a full SMS platform. It does not replace Postscript or Klaviyo for broadcast campaigns, list growth, or general automations. The scope is deliberately narrow: abandoned cart recovery via conversational SMS.
The pricing structure runs on performance tiers:
- Starter: $0/month + 15% of attributed revenue
- Growth: $49/month + 7.5% of attributed revenue
- Scale: $299/month + 2.5% of attributed revenue
- Enterprise: $249/month + 2.5% of attributed revenue
TxtCart reports 15-25% cart recovery rates versus 3-5% for email cart recovery (vendor-reported, not independently verified; treat as directional). The company reports $100 million-plus in SMS-attributed merchant revenue as of February 2026 (company-reported figure; verify at source).
Pricing Math: 100 vs 500 Recovered Orders per Month
The math at 100 recovered orders per month at $50 average order value — $5,000 attributed revenue:
| Plan | Monthly cost breakdown | Total |
|---|---|---|
| Starter (15%) | $0 + $750 | $750 |
| Growth $49/mo (7.5%) | $49 + $375 | $424 |
| Scale $299/mo (2.5%) | $299 + $125 | $424 |
At 100 orders, the $49 and $299 plans nearly tie. The Starter fee of $750 is substantially higher than either paid tier.
At 500 recovered orders per month — $25,000 attributed revenue:
| Plan | Monthly cost breakdown | Total |
|---|---|---|
| Starter (15%) | $0 + $3,750 | $3,750 |
| Growth $49/mo (7.5%) | $49 + $1,875 | $1,924 |
| Scale $299/mo (2.5%) | $299 + $625 | $924 |
The $299 Scale plan pays back its fee at approximately $10,000 per month in attributed recovery. Below that threshold, the $49 Growth plan wins on economics. The Starter tier becomes expensive at volume — but at zero volume, it costs nothing.
Before scaling past Starter, install an attribution tool to measure SMS ROI — TxtCart-attributed revenue uses a click window, and understanding that methodology before comparing it against email cart-recovery numbers prevents inflated expectations.
What TxtCart Is NOT
TxtCart doesn’t handle broadcast campaigns, promotional sends, post-purchase sequences, or keyword opt-in programs. Stores that need a full SMS channel need a different tool — or TxtCart stacked on top of Klaviyo email, not as a replacement.
The rev-share model earns genuine credibility on Starter: paying 15% of $0 in recovery is $0. The downside is time — setup, 10DLC registration, and monitoring a new tool. That is the real cost of the free tier.
Best for: Stores where cart abandonment is a known revenue leak, wanting to test SMS recovery without a monthly fee commitment before validating the channel.
The Verdict by Store Situation
Most articles on this topic recommend Postscript to stores that can’t extract enough value from it, and undersell how much Klaviyo SMS simplifies the decision for stores already on Klaviyo email.
Situation 1 — Migrating from SMSBump: The fastest path is Klaviyo SMS if already on Klaviyo email. If not on Klaviyo, Omnisend offers a direct migration path (it was one of two tools Yotpo pointed departing merchants toward) and warrants evaluation before defaulting to Postscript or TxtCart.
Situation 2 — On Klaviyo email, no SMS yet: Activate Klaviyo SMS for approximately $15/month. Run a 60-day test on cart abandonment plus post-purchase. Do not buy a second dedicated SMS platform until SMS proves it moves the needle. One community voice on r/shopify put it plainly: “Only install 3rd party apps when you 100% need them.”
Situation 3 — Not on Klaviyo, want to test cart recovery only: TxtCart Starter at $0/month plus 15% attributed revenue. Zero downside on a monthly basis, single use case, no new broadcast platform to learn.
Situation 4 — $20k-plus per month, building SMS as a primary channel: Postscript. The Shopify-native segmentation depth, 65-plus automation triggers, and conversational flow capabilities justify the cost at that scale. Not before.
The red flag: Running both Postscript and Klaviyo SMS simultaneously. It double-counts revenue, confuses contact profiles, and burns money on two platform fees for the same channel. Pick one.
For post-purchase flows, pair SMS with a review app to pair with your SMS post-purchase flows — review requests sent via SMS in the 24-hour post-delivery window convert at higher rates than email in most categories.
Most stores under $30k/month don’t run enough SMS volume to make Postscript’s per-message pricing worth it versus Klaviyo’s bundled add-on. The exception is operators explicitly building SMS as a primary acquisition and retention channel — they should go to Postscript from day one.
Frequently Asked Questions
SMSBump shut down — what should I switch to?
Klaviyo SMS is the fastest migration path for stores already on Klaviyo email — existing profile data, segments, and flows transfer with minimal rework. Stores not on Klaviyo should evaluate Omnisend first; it was one of two platforms Yotpo pointed departing merchants toward and has a documented migration path. Postscript is the right destination for stores building a full dedicated SMS program. TxtCart fits if cart recovery is the primary use case.
Is Postscript worth it under $20k/month?
The economics are tight. The all-in per-message cost on the free plan runs approximately $0.019 — roughly $19 per 1,000 sends, $95 per 5,000. At that volume, SMS needs to recover enough margin to justify the spend before the tool proves its value. For most stores under $20k/month, Klaviyo SMS bundled with an existing email plan is a more rational starting point unless the store has already validated SMS as a revenue channel.
Does Klaviyo SMS remove the need for a separate SMS app?
For campaigns, abandoned cart sequences, and post-purchase automations, yes. For AI-assisted conversational cart recovery specifically, TxtCart adds capability Klaviyo’s SMS doesn’t replicate. Most stores under $30k/month don’t need that additional layer — activate Klaviyo SMS first and evaluate whether the gap matters before adding another platform.
What does TxtCart actually cost at 100 vs 500 recovered orders per month?
At 100 orders per month with $50 average order value ($5,000 attributed): Starter costs $750, the $49 Growth plan costs approximately $424. At 500 orders per month ($25,000 attributed): Starter costs $3,750, the $49 Growth plan costs approximately $1,924, the $299 Scale plan costs approximately $924. The $49 plan beats Starter at around $650/month in attributed recovery. Verify with your own attribution methodology — TxtCart uses a click window that may differ from how email cart recovery is measured.
What is the lowest real cost to start SMS?
TxtCart Starter is $0/month plus 15% of attributed recovery — no recovery means no cost. Klaviyo SMS on the free plan includes 150 SMS credits before any charge. Postscript’s free plan charges per message from the first send. All three require 10DLC brand registration — approximately $4 for sole proprietors, $48-plus for standard business entities — plus ongoing carrier passthrough fees. Factor both as baseline costs regardless of platform.
How complicated is 10DLC for a small store?
All three platforms walk merchants through the process during setup. Brand registration takes two to five business days. The fee is approximately $4 for sole proprietors, $48-plus for standard entities. Since February 1, 2025, unregistered A2P SMS is blocked by carriers entirely — it does not deliver at reduced rates, it does not deliver at all. Budget one to two weeks between account creation and first compliant send, and plan the migration or launch timeline accordingly.
Is SMS worth it at all for a small store?
Category and average order value matter significantly. SMS performs best for products with AOV above $40 in categories with emotional or time-sensitive purchase decisions — apparel, beauty, home goods, food. Commodity or thin-margin categories may not generate enough incremental recovery to justify the overhead. The lowest-risk test is TxtCart Starter or Klaviyo’s free SMS credits before committing to a full program and 10DLC registration costs.
The Bottom Line on SMS Tool Selection
For most stores under $30k/month, Klaviyo SMS is the default — not because it’s the most capable SMS platform, but because it’s already in the stack for any store running Klaviyo email, and testing SMS for $15/month extra is a lower-risk move than onboarding a separate tool the store may lack volume to justify.
Migrating from SMSBump: export the list now, register a 10DLC brand, and activate Klaviyo SMS or TxtCart Starter based on primary use case. Starting from scratch: run 60 days on Klaviyo SMS or TxtCart Starter before evaluating Postscript.
SMS is a real channel — but it is not a revenue miracle, and the wrong tool at the wrong store size is just a subscription that will eventually get cancelled.
Sources
Yotpo/SMSBump shutdown (Dec 31, 2025; announced Aug 5, 2025; approx. 25,000 merchants; approx. 200 layoffs) reported by Spam Resource and Dondy. Pricing from Postscript, Klaviyo, and TxtCart public pages and the Shopify App Store, verified July 2026; pricing as of 2026 — verify at source before purchasing. 10DLC brand-registration fees and the Feb 1, 2025 A2P blocking enforcement per The Campaign Registry. Community experience accounts sourced from r/shopify and aggregated G2 reviews; no usernames referenced. TxtCart recovery-rate and revenue figures are vendor-reported and directional; verify at source.
