Two tools, two different buyers
PostHog Workflows and Iterable show up in the same search results because both can send a message when a user does something. The overlap ends there. PostHog Workflows is a feature inside a product analytics suite. Iterable is a cross-channel marketing platform that expects a team to run it.
If you are an engineer or product manager at a startup that already ships events to PostHog, Workflows is the path of least resistance. You build a trigger from an event or cohort, add a delay or a branch, and send an email, post to Slack, fire a webhook or update a person property. There is no second data model to maintain.
If you are a lifecycle marketing lead at a company with a large customer base, several channels and a quarterly campaign plan, Iterable is designed for you. It assumes customer data arrives through a pipeline, that more than one person builds journeys, and that experiments and approvals are part of the job.
What PostHog Workflows does well
The strongest argument for PostHog Workflows is proximity. The cohort you used to find users who stalled at step three of onboarding is the same cohort that triggers the email. You never export it, rebuild it in another tool, or wonder why the two counts differ.
A few workflows fit naturally:
- A user signs up but has not created a project after 48 hours, so you send a short nudge with a link to the setup guide.
- An account on the free plan crosses a usage threshold, so you post to the sales Slack channel with the account name.
- A feature flag rollout reaches a user, so you send an announcement email only to that cohort.
- A user triggers an error event repeatedly, so you call a webhook that opens a support ticket.
Templates live in a content library and personalize with person properties. Opt-outs are handled through message categories, per-recipient preferences and a suppression list built from bounces. Workflows can also be managed through PostHog's REST API and MCP server.
What Iterable does that PostHog cannot
Channel orchestration. A single Iterable journey can send an email, wait, check engagement, then fall back to push or SMS and show an in-app message on next login. PostHog Workflows can branch and send to several destinations, but it has no in-app messaging and push is still in beta.
Governance. Iterable supports what large teams need: shared template libraries, review before launch, role-based access and experimentation designed for marketers rather than product engineers.
Audience depth. Iterable's segmentation and personalization run on a customer profile fed from many sources. PostHog's cohorts are strong for product behavior but are not built for catalog data or marketing attributes gathered from several systems.
The contract question
This is the tension that decides most evaluations. PostHog publishes every Workflows rate on its pricing page, and you can start on the free allowance today without talking to anyone. Iterable publishes no price table. You talk to sales, scope channels, audience size and support, and sign a contract. Third-party reviews of Iterable describe pricing as quote-based and typically landing in the five-figure annual range.
Neither model is wrong. A negotiated contract buys implementation help, support commitments and a platform that will not change its price mid-year. A rate card buys the ability to start small and stop at any time. The question is whether your messaging program is mature enough to justify a commitment.
Pricing reality at 100,000 emails a month
Here is a worked example for a SaaS product sending 100,000 automated emails a month, using PostHog's published graduated tiers.
| Line item | PostHog Workflows | Iterable | Sequenzy |
|---|---|---|---|
| First 10,000 emails | Free | Part of quote | Included in plan |
| Next 40,000 emails | 40,000 x $0.003 = $120 | Part of quote | Included in plan |
| Next 50,000 emails | 50,000 x $0.0018 = $90 | Part of quote | Included in plan |
| Monthly total | About $210, plus PostHog analytics usage | Custom contract | $99 plan covers 120,000 emails |
| Commitment | None | Contract term | Monthly or yearly |
The PostHog number excludes Slack and webhook dispatches, which have their own free 10,000 and then start at $0.00075 each. The Iterable number depends entirely on your quote, so ask for it in writing with channels and volume spelled out.
The data pipeline tax
PostHog Workflows reads events where they already live. Iterable needs those events shipped in through its API, SDKs or a customer data platform, and someone must keep the schema in sync as your product changes. Rename an event in your app and an Iterable journey can quietly stop firing.
For companies that already run a CDP or warehouse sync, this is routine. For a startup whose only tracking is the PostHog snippet, it is a new system to own. Budget engineering time for the pipeline, not just the journey rebuild.
Governance and who touches production
In PostHog, whoever has project access can publish a workflow that emails real users. That speed is the point for a small team, and a risk for a large one. Iterable is built for organizations where a copywriter drafts, a lifecycle manager builds, and someone else approves before anything goes live.
If you have ever had to apologize for a test email sent to the whole user base, you understand why larger companies pay for that structure.
Deliverability and sending setup
PostHog Workflows sends from a domain you verify with a few DNS records, on infrastructure PostHog manages. PostHog enforces sending standards across projects and can suspend a project's workflow email if problems arise, which matters if your list quality is uncertain. At enterprise volume, Iterable customers usually discuss dedicated IPs and deliverability support as part of the contract. Confirm what your quote includes before assuming either.
Review signals
Iterable holds a 4.4 out of 5 rating on G2 across more than 800 reviews. Reviewers praise multi-channel campaign building, personalization and support. Common complaints are a steep learning curve for non-technical marketers, reporting that could go deeper, and cost that scales with contacts and channels. PostHog Workflows is newer, and independent reviews of it specifically are still sparse; most feedback focuses on its close tie to analytics and a lighter email editor than dedicated tools.
The team in the middle
Plenty of SaaS companies sit between these tools. PostHog Workflows handled the first onboarding nudges, but now marketing wants a newsletter, sales wants trial-ending sequences split by plan, and finance wants dunning emails. Staying in PostHog means running campaigns in a tool whose email features are secondary. Buying Iterable means paying for push, in-app and governance you may not use yet.
Use-case matchups
| Need | Better fit | Why |
|---|---|---|
| Nudge users who stall in a PostHog funnel | PostHog Workflows | The cohort already exists and triggers directly |
| Slack alert when a target account gets active | PostHog Workflows | Internal dispatches are built in and cheap |
| Email, push and in-app in one consumer journey | Iterable | Cross-channel orchestration is its core |
| Campaign approvals across a marketing team | Iterable | Governance is designed for multi-person teams |
| Trial ending and failed payment emails from Stripe | Sequenzy | Billing events are native triggers |
Where Sequenzy fits
Sequenzy is an email platform for SaaS: campaigns, automated sequences, transactional email and an SMS add-on for US and Canada numbers. It connects to Stripe, so trial ending, payment failed, upgrade and cancellation are available as triggers and segments. Its native PostHog integration receives events through a PostHog destination, and a history import can backfill recent events from PostHog Cloud. Pricing is by emails sent with unlimited contacts, from free for 2,500 emails a month to $49 for 60,000.
Iterable still wins if you need push and in-app in the same journey, approvals across teams, or enterprise support contracts. PostHog still wins for Slack alerts, webhooks and property updates.
Migration checklist
| Workstream | PostHog Workflows to Iterable | Iterable to PostHog Workflows |
|---|---|---|
| Events | Build a pipeline from your app or PostHog into Iterable | Confirm every trigger event exists in PostHog |
| Audiences | Recreate cohorts as Iterable segments | Rebuild segments as PostHog cohorts |
| Journeys | Rebuild each workflow as a journey | Rebuild email steps; push and in-app need another home |
| Templates | Move HTML and remap personalization fields | Export HTML and recreate in the content library |
| Unsubscribes | Import PostHog opt-outs before first send | Import Iterable unsubscribes into the suppression list |
| Domain | Add Iterable DNS records and warm up volume | Verify the domain in PostHog and ramp gradually |
Decision checklist
- Choose PostHog Workflows if your messages react to product behavior, one team owns them, and you want a public price.
- Choose Iterable if a dedicated lifecycle team runs cross-channel journeys and needs approvals, and you have budget for a negotiated contract.
- Avoid Iterable if your only data source is the PostHog snippet and nobody owns a pipeline.
- Avoid PostHog Workflows as your only email tool once marketing needs newsletters and transactional templates.
- Consider Sequenzy if email is your main channel, billing moments matter, and PostHog should stay your analytics source.
