Softwr

Marketing · head to head

Postscript vs Shortwave

Postscript logo

Postscript

Marketing

SMS marketing built for Shopify merchants, with carrier fees billed on top of message rates

From
$49/month
Rated
-
Full reviewWebsite
Shortwave logo

Shortwave

Email Marketing

AI-powered email assistant for intelligent inbox management

From
Free
Rated
-
Full reviewWebsite

The short version

  • Only Shortwave has a free tier, so it costs nothing to try first.
  • Each has a real cost: Postscript carrier pass-through fees are billed on top of the per-message rate, roughly $0.00418 per SMS and $0.00841 per MMS in the United States, and are routinely missing from the cost comparisons buyers build.; Shortwave per-seat pricing increases team costs compared to flat-rate email solutions
  • They diverge on capability: Postscript covers Shopify segmentation, Shortwave covers AI Email Filtering.
  • Prices and features above were last checked on 31 August 2026.

Where they differ

Only the attributes on which Postscript and Shortwave actually diverge.

Attributes where Postscript and Shortwave differ
AttributePostscriptShortwave
Starting price$49/monthFree
Pricing modelPer month plus per message sentUnknown
Free tierNoYes
PlatformsWeb, iOSiOS, Android, macOS, Windows
CategoryMarketingEmail Marketing

Identical on both: user rating (Not yet rated).

What each one covers

Drawn from each product's published feature list. An absence here means we hold no record of it - not that the product lacks it.

Only in Postscript

  • Shopify segmentation
  • Automated flows
  • Subscriber acquisition
  • Two-way conversations
  • MMS campaigns
  • Revenue attribution
  • Headless SDK
  • Usage-based tiers

Only in Shortwave

  • AI Email Filtering
  • Intelligent Autocomplete
  • Voice-Style Composition
  • Meeting Scheduling
  • Email-to-Todo Conversion
  • AI-Powered Search
  • Team Collaboration
  • Email Summaries

What people use each for

The jobs each tool is most often brought in to do.

Postscript

  • A Shopify direct-to-consumer brand that wants abandoned cart recovery by text rather than another email in an ignored inboxnot Shortwave
  • A brand running a product drop where a timed broadcast to an opted-in list is the whole launch mechanismnot Shortwave
  • A merchant segmenting by past purchase and variant to send replenishment reminders at the right intervalnot Shortwave
  • A store on headless Shopify or a custom stack that still wants SMS built on order data through the SDKnot Shortwave

Shortwave

  • Reducing inbox overload through AI-powered organizationnot Postscript
  • Drafting professional emails using natural languagenot Postscript
  • Scheduling meetings without back-and-forth coordinationnot Postscript
  • Searching email archives using conversational queriesnot Postscript
  • Converting emails to tasks for team task trackingnot Postscript

Where each one falls short

Documented limitations, not opinions. Every one is a constraint you would hit in normal use.

Postscript

  • Carrier pass-through fees are billed on top of the per-message rate, roughly $0.00418 per SMS and $0.00841 per MMS in the United States, and are routinely missing from the cost comparisons buyers build.
  • The cheapest per-message rates require the $500 a month plan, so a small sender pays more than double the headline low rate per text.
  • The $0 Starter plan carries a $49 minimum monthly spend, so it is not a free tier and quiet months still generate a bill.
  • US SMS marketing carries real legal exposure under consent, quiet hours and carrier registration rules, and the compliance obligation sits with the merchant, not the platform.
  • It is SMS and MMS only, so email, push and on-site messaging live in a separate tool and audience suppression between the two has to be managed across systems.

Shortwave

  • Per-seat pricing increases team costs compared to flat-rate email solutions
  • AI features may require higher tier plans, limiting value for smaller teams
  • Dependency on third-party integrations for full feature depth
  • Learning curve for effective use of AI-powered features
  • Limited customization for AI filter behavior compared to manual rules

Pricing, plan by plan

Postscript

$49/month
  • Starter$49/month
    • $0 base fee but a $49 minimum monthly spend
    • SMS at $0.015 and MMS at $0.045 per message
    • Campaigns, automations, acquisition tools and analytics
  • Growth$100/month
    • Lower per-message rates than Starter
    • Full campaign and automation feature set
    • No contract required
  • Professional$500/month
    • Rates falling towards $0.007 SMS and $0.024 MMS
    • Suited to high-volume senders
    • Upgrade or downgrade at any time
  • Enterprise$undefined/month
    • Custom pricing on a contract
    • Negotiated message rates and support terms

Shortwave

Free
  • FreeFree
    • Email search and organization
    • Basic inbox tools
    • Limited AI features
  • Business$30/month
    • Full standard search history
    • 5 years AI search history
    • Max 50 threads per AI search
  • Premier$45/month
    • Everything in Business
    • 2x more AI usage
    • Unlimited AI search history
  • Max$120/month
    • Everything in Premier
    • 6x more AI usage
    • Max 150 threads per AI search

Which should you pick?

Choose Postscript if

  • You need shopify segmentation.
  • You work on Web, iOS.
  • You also want automated flows.
Postscript review

Choose Shortwave if

  • You need ai email filtering.
  • You want to start without paying.
  • You work on iOS, Android, macOS, Windows.
  • You also want intelligent autocomplete.
Shortwave review

Questions people ask

Is Postscript or Shortwave better?
Neither clearly leads. Postscript starts at $49/month and Shortwave at Free, and user ratings are close enough to be indistinguishable. Choose on capability and platform support.
Which is cheaper, Postscript or Shortwave?
Shortwave has a free tier; the other does not. Paid plans start at $49/month for Postscript and Free for Shortwave.
Does Postscript or Shortwave run on more platforms?
Postscript runs on Web, iOS. Shortwave runs on iOS, Android, macOS, Windows.
Can I use Shortwave for free?
Yes. Shortwave has a free tier, so you can try it without paying. Postscript starts at $49/month.
What is Postscript best used for?
Postscript is most often used for a shopify direct-to-consumer brand that wants abandoned cart recovery by text rather than another email in an ignored inbox, a brand running a product drop where a timed broadcast to an opted-in list is the whole launch mechanism, a merchant segmenting by past purchase and variant to send replenishment reminders at the right interval, a store on headless shopify or a custom stack that still wants sms built on order data through the sdk. Of those, a shopify direct-to-consumer brand that wants abandoned cart recovery by text rather than another email in an ignored inbox and a brand running a product drop where a timed broadcast to an opted-in list is the whole launch mechanism are not what Shortwave is typically brought in for.
What can Postscript do that Shortwave cannot?
Postscript covers Shopify segmentation, Automated flows, Subscriber acquisition, Two-way conversations. Shortwave covers AI Email Filtering, Intelligent Autocomplete, Voice-Style Composition, Meeting Scheduling.

Answered from the vendors’ own pages

Postscript: Is Postscript only for Shopify?

It is built for Shopify and that is where its segmentation advantage lies, but headless and non-Shopify stores are supported through an SDK with more setup work.

Shortwave: Is there a free trial for Shortwave?

Yes, Shortwave offers a 14-day free trial for all paid plans with no credit card required.

Source
Postscript: What is the real cost per text?

The plan rate plus carrier fees. On Starter that is about $0.015 plus roughly $0.00418 in US carrier fees per SMS, so budget close to two cents a message before discounts.

Shortwave: What platforms does Shortwave support?

Shortwave is available on iOS, Android, macOS, and Windows for full cross-platform email management.

Source
Postscript: Is the Starter plan free?

No. The base fee is $0 but there is a $49 minimum monthly spend, so it functions as a $49 floor.

Shortwave: How much AI usage do I get per plan?

Business plan includes 3 AI-powered filters and standard AI usage. Premier (2x more AI) and Max (6x more AI) plans provide increasing levels of AI feature access.

Source
Postscript: Do I need a contract?

No. Contracts are offered but not required, and plans can be moved up or down at any time under usage-based billing.

Shortwave: What integrations does Shortwave support?

Shortwave integrates with Slack, Calendar, Notion, Asana, HubSpot, and 3,000+ apps via Tasklet.

Source
Share

Related pages

More on Postscript

More on Shortwave

Keep looking

Other head to heads