SQS vs SNS vs EventBridge cost: pricing three messaging services

Quick answer

SQS bills per request (batches of messages count as fewer requests), so it is cheapest for high-volume point-to-point queuing. SNS bills per publish plus per delivery to each subscriber, so fan-out cost scales with the number of subscribers. EventBridge bills per event published to a custom bus with content-based routing and integrations, at a higher per-event rate but with routing and transformation built in. The cheapest choice depends on the pattern: SQS for cheap queuing, SNS for simple fan-out, EventBridge for routed, integrated event-driven architectures where its features justify the higher rate.

AWS gives you three ways to move messages between services, and they look interchangeable until you compare the bill. SQS, SNS, and EventBridge each price differently and suit different patterns, so choosing on cost means matching the service to how your messages actually flow: point-to-point queuing, one-to-many fan-out, or routed event-driven integration.

How the three price

Service	Billing basis	Best for
SQS	Per request (batching helps)	High-volume point-to-point queuing
SNS	Per publish plus per delivery	Simple fan-out to subscribers
EventBridge	Per event, with routing built in	Routed, integrated event architectures

SQS charges per request, and because you can batch multiple messages per request, high-volume queuing gets cheaper per message with batching. SNS charges per publish and then per delivery to each subscriber, so its cost grows with fan-out breadth. EventBridge charges per event on a custom bus but includes content-based routing, filtering, transformation, and many native integrations, at a higher per-event rate.

When SQS is cheapest

For high-volume point-to-point queuing, decoupling a producer from a consumer, SQS is usually the cheapest, especially with batching that packs many messages into each billed request. If you just need a durable queue between two components at scale, SQS's per-request model with batching is hard to beat. It pairs naturally with Lambda or container consumers processing the queue.

When SNS or EventBridge fits

SNS suits simple fan-out: publish once, deliver to several subscribers (queues, functions, endpoints). Its per-delivery cost is fine when the subscriber count is modest, but watch it grow with wide fan-out. EventBridge suits event-driven architectures that need content-based routing, filtering, and integration with many AWS and SaaS targets, its higher per-event rate buys routing you would otherwise build yourself. For step-by-step orchestration, compare with Step Functions, which prices per state transition.

Choosing on cost and pattern

Match the service to the pattern: SQS for cheap durable queuing, SNS for straightforward fan-out, EventBridge when routing and integrations justify the rate. Often you combine them (SNS fanning out to SQS queues is a classic pattern). Estimate message volume, fan-out breadth, and routing needs, then price each. These are small per-message charges that add up at scale, part of the same family as other easily-overlooked charges. Price your messaging against the resource catalog so the pattern's cost is clear before you build it.

FAQ

How do SQS, SNS, and EventBridge differ in cost?

SQS bills per request, and batching multiple messages per request lowers the per-message cost, so it is cheapest for high-volume queuing. SNS bills per publish plus per delivery to each subscriber, so cost scales with fan-out breadth. EventBridge bills per event on a custom bus at a higher per-event rate but includes content-based routing, filtering, and integrations. The cheapest choice depends on your messaging pattern.

Which is cheapest for high message volume?

SQS is usually cheapest for high-volume point-to-point queuing, because it charges per request and you can batch multiple messages into each billed request, lowering the per-message cost significantly. For simply decoupling a producer from a consumer at scale, SQS's per-request model with batching is hard to beat, making it the default cheap choice for durable queuing.

When should I use SNS?

For simple fan-out: publish a message once and deliver it to several subscribers such as SQS queues, Lambda functions, or HTTP endpoints. SNS is cost-effective when the subscriber count is modest, since it charges per publish plus per delivery. Watch the per-delivery cost grow with wide fan-out to many subscribers, but for straightforward one-to-many distribution it is the natural fit.

When is EventBridge worth its higher rate?

When your event-driven architecture needs content-based routing, event filtering, transformation, and integration with many AWS and SaaS targets. EventBridge's higher per-event rate buys routing and integration capabilities you would otherwise build and maintain yourself, so it is worth it when those features matter. For simple queuing or fan-out without routing, SQS or SNS is cheaper.

Can I combine these messaging services?

Yes, and it is common. A classic pattern is SNS fanning out to multiple SQS queues, combining SNS's one-to-many distribution with SQS's cheap durable queuing per consumer. EventBridge can also route events to SQS or SNS targets. Combining them lets you use each where it is cost-effective, cheap queuing with SQS, fan-out with SNS, and routing with EventBridge, within one architecture.

How does C3X help with messaging cost?

C3X prices your messaging infrastructure, SQS queues, SNS topics, and EventBridge buses, from Terraform before you deploy, so the cost model of a messaging pattern is visible in the pull request. That helps you match the service to your fan-out and routing needs at design time and catch a pattern whose per-message charges would add up at scale, before it ships.

What to do next

Price your messaging pattern before you build it. C3X reads your Terraform and prices your resources against a live catalog. Start with the quickstart.