OneSignal vs Siren
An independent, review-free comparison compiled by the SaaSTracker editorial team. Both products are profiled in full, and neither can pay for placement here.
Still shortlisting? Browse the best in Notification Infrastructure for every option we track, with award winners called out.
The short answer
Both sides assessedOneSignal compared with Siren
Opposite ends of the same word. OneSignal sends, with its own delivery included, deep mobile and web push, segmentation, and a free tier that carries a real programme. Siren sends nothing itself; it routes across nine channels through your own vendor accounts, with workflows, provider pools, campaigns, and an agent toolkit, at $249 a month with no free tier. They coexist happily: OneSignal can be the push provider inside a Siren workflow. Pick OneSignal for a push campaign to a mobile audience, and Siren when an application or an AI agent has to reach the right person on whichever channel they use.
Siren compared with OneSignal
Different buyers entirely. OneSignal is a growth team's tool with push as its deepest channel, its own delivery included, and a free tier generous enough to run a real mobile program. Siren sends nothing itself, assumes engineering, and exists to route product and agent notifications across nine channels through your own vendors. If the question is how to run a push campaign to a mobile audience, OneSignal, and OneSignal can even be the push provider inside a Siren workflow. If the question is how an agent tells the right person the right thing on the right channel, Siren.
Choose OneSignal if
Consumer mobile apps, marketplaces, media sites, and web publishers whose primary channel is push notifications, especially teams that want serious push infrastructure and a workable email and in-app layer for free or for tens of dollars a month rather than hundreds.
Choose Siren if
Product and platform teams shipping multi-channel notifications where an AI agent is one of the senders, where the audience lives on WhatsApp, LINE, or Discord as well as email, or where the in-app inbox has to render in Vue, Flutter, or native Android rather than React.
Side by side
16 attributes| Attribute | OneSignal | Siren |
|---|---|---|
| Category | Notifications | Notifications |
| Starting price | $0 (Free), then $19 per month plus usage (Growth) | $249 per month, or $208 per month billed annually (7 days trial) |
| Pricing model | Per-channel usage metering rather than a single contact-count meter: mobile push billed per monthly active user, web push per subscriber, email per thousand sends, with a small platform fee on Growth and quoted annual contracts above it. | A single published subscription priced on notification volume, with hard caps on stored users, campaigns, team members, and log retention, sold above a seven-day full-feature trial. No permanent free tier. |
| Free plan | Unlimited mobile push sends, web push up to 10,000 subscribers per send, 10,000 email sends per month, and one active in-app message, with no expiry. | No |
| Free trial | No fixed trial; the permanently free plan is the evaluation path | 7 days with everything unlocked, no credit card required |
| Best for | Consumer mobile apps, marketplaces, media sites, and web publishers whose primary channel is push notifications, especially teams that want serious push infrastructure and a workable email and in-app layer for free or for tens of dollars a month rather than hundreds. | Product and platform teams shipping multi-channel notifications where an AI agent is one of the senders, where the audience lives on WhatsApp, LINE, or Discord as well as email, or where the in-app inbox has to render in Vue, Flutter, or native Android rather than React. |
| Setup time | Under an hour for web push (a script tag) and a few hours for a mobile app, most of which is spent on APNs certificates and Firebase configuration rather than on OneSignal itself. Journeys can be running the same day. | An afternoon to a first notification using QuickSend, and a few days to a published multi-channel workflow with templates and a provider configured. The MCP server and agent toolkit shorten the first integration considerably when the trigger is an agent rather than a service. |
| Learning curve | Low for push and in-app, moderate for Journeys. The tag model is easy to grasp but easy to abuse, and teams who tag indiscriminately end up with segmentation logic nobody can audit six months later. Agree a tag naming convention before you start. | Low for engineers. The model is small: users or inline recipients, templates per channel, workflows made of nodes, providers behind them. The concepts that take longest are provider pools and which workspace a key belongs to. |
| Platforms | Web app, Android SDK, iOS SDK, Flutter, React Native, Expo, Unity, Web push script, REST API | Web dashboard, REST API, MCP server, Python and TypeScript server SDKs, JavaScript, React, and Vue web SDKs, React Native, Android, and Flutter mobile SDKs |
| Compliance | SOC 2, GDPR, CCPA | None published |
| Founded | 2014 | 2024 |
| Headquarters | San Mateo, California, United States | Kochi, Kerala, India |
| Ownership | Venture-backed | Bootstrapped. Built and operated by KeyValue Software Systems Private Limited, a product engineering studio running since 2017. |
| Free tier volume | Unlimited mobile push sends, 10,000 web push subscribers and 10,000 email sends per month | None; 7-day full-feature trial only |
| First paid tier | $19 per month (Growth) plus per-channel usage | $249 per month, or $208 per month billed annually (Pro) |
| Self-hosting | Not offered; managed cloud only | Not offered; managed cloud only |
Strengths and limitations
OneSignal
Strengths
- The best push implementation in this category by a wide margin, covering mobile, web, rich media, per-platform payload control, confirmed delivery reporting, and iOS Live Activities.
- A permanently free plan with unlimited mobile push, which removes the budget conversation entirely for early-stage consumer apps.
- Per-channel usage metering means a big dormant contact database costs nothing, the opposite of profile-based platforms where dead contacts are billable.
- First-party SDKs for Android, iOS, Flutter, React Native, Expo, and Unity that handle the permission and certificate plumbing teams usually get wrong.
Limitations
- SMS and RCS are locked behind an annual quoted Professional contract, so the cheapest self-serve path to SMS is a different vendor entirely.
- Segmentation is tag, session, and device based rather than a full behavioral event store, so sequence-dependent targeting is harder here than in Customer.io or Vero.
- No native account or company object, which makes B2B SaaS lifecycle logic awkward and rules the platform out for anyone whose messaging is organization-shaped.
- Email is a competent secondary channel, not a strong one; template tooling and list management are thinner than in email-first products.
Siren
Strengths
- Nine channels out of the box including WhatsApp, Discord, and LINE, which is broader than any other platform in this category at a published price.
- In-app inbox SDKs for JavaScript, React, Vue, React Native, Android, and Flutter, so teams outside the React default get a supported component rather than a REST endpoint.
- Provider pools give genuine vendor redundancy with per-provider message limits and automatic rollover, which most rivals leave as a single configured sender per channel.
- The agent surface is real and specific: an MCP server, function-calling toolkits for OpenAI, LangChain, and Vercel, and a chat node that holds a workflow open while a human answers in Slack, Teams, or Gmail.
Limitations
- No free plan at all. Seven days of trial, then $249 a month, which is the hardest entry in the category and rules out hobby projects and long evaluations.
- No batching or digest primitive anywhere in the product or the documentation, and collapsing nine events into one notification is the single most common reason teams buy a platform like this.
- 500 stored users on the published plan, with campaigns and cohorts bounded by it, so consumer-scale list work needs an Enterprise conversation immediately.
- No published compliance attestations. There is no SOC 2 report, ISO certification, or HIPAA statement in the public documentation, which will stall procurement at any regulated buyer.
Pricing compared
OneSignal
Per-channel usage metering rather than a single contact-count meter: mobile push billed per monthly active user, web push per subscriber, email per thousand sends, with a small platform fee on Growth and quoted annual contracts above it.
- Free$0
- Growth$19
- ProfessionalCustom
- EnterpriseCustom
Judged per dollar, OneSignal is the cheapest serious multi-channel platform a small company can buy, and by some distance. Unlimited mobile push at $0 is not a loss leader trick, it is the product, and Growth at $19 plus a per-MAU rate keeps a 5,000-user app under $100 a month with email, in-app, and Journeys included. What you are not buying is a data platform: segmentation is tag and session based rather than a real behavioral event store, there is no account model, and email is a channel rather than a deliverability practice. The value is exceptional if push is your primary channel and merely fine if it is your third.
Siren
A single published subscription priced on notification volume, with hard caps on stored users, campaigns, team members, and log retention, sold above a seven-day full-feature trial. No permanent free tier.
- Free trial$0
- Pro$249
- EnterpriseCustom
On raw allowance Siren is the best value at its price point in this category: 100,000 notifications, unlimited workflows and templates, cohorts, campaigns, and nine channels for $249 a month, against 50,000 messages for $250 at Knock and 50,000 deliveries for $249 at MagicBell. The catch is the shape of the plan rather than the number. No free tier means you cannot prove the thing in production before paying, 500 stored users rules out consumer audiences on the published plan, and 30 days of logs is short for anything audited. For a small B2B product sending tens of thousands of notifications a month across several channels, this is the most capability per dollar on offer. For a team that wants to start at zero and grow into a bill, it is the wrong door.
Editorial verdict on each
OneSignal
OneSignal is the correct first choice for any small company whose primary channel is push. Nothing else in this category gives away unlimited mobile push, and nothing else handles APNs, FCM, web push, and Live Activities with this much per-platform care. Growth at $19 plus $0.012 per monthly active user keeps a real consumer app under $100 a month with Journeys, in-app messaging, and email included, and the per-channel meter means a large dormant install base costs you nothing. The limits are equally clear: segmentation is tags and sessions rather than a behavioral event store, there is no account model for B2B, email is adequate rather than good, and SMS demands an annual quoted contract. Buy it for push, keep it for in-app and email, and pair it with something else if your lifecycle logic is really about product events or company records.
Read the full OneSignal profileSiren
Siren is the pick when the notification problem has moved past email and Slack, and especially when an agent is one of the things doing the notifying. Nine channels, six front-end SDKs, provider pools that fail over between vendors, campaigns with a database connection, and an MCP server that makes a workflow trigger a tool call add up to more product than anything else at $249 a month, and the 100,000 notification allowance is twice what the two closest-priced rivals include. The reasons to walk away are concrete rather than aesthetic: no free tier means you cannot prove it in production first, there is no batching or digest primitive at all, 500 stored users bounds anything list-driven, and no compliance attestation is published. For a small B2B team sending across many channels with an agent in the loop, it is worth the trial week. For a team whose first requirement is a digest, or whose security review needs a SOC 2 report, look at Knock, Novu, or SuprSend instead.
Read the full Siren profileOneSignal profile last reviewed 2026-09-07; Siren last reviewed 2026-09-13. Pricing is compiled from public sources and can change without notice. See our methodology.
The best in Notification Infrastructure
9 trackedNotification infrastructure platforms sit between an application and its delivery providers, turning one API call into orchestrated in-app, email, push, SMS, and chat notifications with batching, digests, preference centres, and per-tenant routing, so product teams stop rebuilding that logic in application code.
Batching, preference centres, and multi-tenancy are first-class rather than roadmap items, and workflows-as-code with environments and rollback makes a notification change a normal deploy.
$30 a month for 30,000 workflow runs, or nothing at all self-hosted, against a category whose next cheapest real plan is $110 and whose leader jumps from free to $250.
Founded in 2022 on roughly $1M, SuprSend shipped nine channels on the free tier, CLI environment promotion, an MCP server, and an Agent SDK while larger rivals were still writing about them.
The delivery planner turns cross-channel escalation into configuration: try in-app, fall back to email only if it goes unread, set as a rule rather than written as application code.
A visual designer that previews every channel on one canvas, and a bill that is $0.005 a send with no seats or channel fees, let a non-developer own the message end to end.
Frequently asked questions
6 questionsWhat is the difference between OneSignal and Siren?
Opposite ends of the same word. OneSignal sends, with its own delivery included, deep mobile and web push, segmentation, and a free tier that carries a real programme. Siren sends nothing itself; it routes across nine channels through your own vendor accounts, with workflows, provider pools, campaigns, and an agent toolkit, at $249 a month with no free tier. They coexist happily: OneSignal can be the push provider inside a Siren workflow. Pick OneSignal for a push campaign to a mobile audience, and Siren when an application or an AI agent has to reach the right person on whichever channel they use.
Is OneSignal or Siren cheaper?
OneSignal starts at $0 (Free), then $19 per month plus usage (Growth). Siren starts at $249 per month, or $208 per month billed annually (7 days trial). The billing models differ, so the entry price is rarely the whole cost. OneSignal pricing model: Per-channel usage metering rather than a single contact-count meter: mobile push billed per monthly active user, web push per subscriber, email per thousand sends, with a small platform fee on Growth and quoted annual contracts above it. Siren pricing model: A single published subscription priced on notification volume, with hard caps on stored users, campaigns, team members, and log retention, sold above a seven-day full-feature trial. No permanent free tier.
Does OneSignal or Siren have a free plan?
OneSignal has a free plan. Unlimited mobile push sends, web push up to 10,000 subscribers per send, 10,000 email sends per month, and one active in-app message, with no expiry. Trial terms: No fixed trial; the permanently free plan is the evaluation path. Siren has no free plan. Trial terms: 7 days with everything unlocked, no credit card required.
Who should choose OneSignal?
Consumer mobile apps, marketplaces, media sites, and web publishers whose primary channel is push notifications, especially teams that want serious push infrastructure and a workable email and in-app layer for free or for tens of dollars a month rather than hundreds.
Who should choose Siren?
Product and platform teams shipping multi-channel notifications where an AI agent is one of the senders, where the audience lives on WhatsApp, LINE, or Discord as well as email, or where the in-app inbox has to render in Vue, Flutter, or native Android rather than React.
What are the best alternatives to OneSignal and Siren?
SaaSTracker profiles 9 products in Notification Infrastructure. The Summer 2026 awards in the category went to Knock (Category Leader), Novu (Best Value), SuprSend (Momentum). Every profile is compiled from primary sources, so a shortlist can be built from pricing, limitations, and fit rather than from star ratings.
