Pricing that grows with usage, not headcount
Sendmux email API pricing is usage-based. You pay $0.15 per 1,000 emails to send through your own providers or to receive, $0.25 per 1,000 through the managed Amazon SES route, and $0.02 per GB of mailbox storage a month. No per-seat fees. No per-mailbox fees. No minimums.
- $0.15/ 1,000
- Send or receive
- $0.25/ 1,000
- Managed Amazon SES
- $0.02/ GB · mo
- Mailbox storage
What it costs
Three numbers. That's the whole price list.
No tiers to decode and no plan to outgrow. Sendmux meters three things by usage, and every charge shows up in your balance and transactions. You start free and only pay once email flows.
Standard email
Outgoing through your own connected providers, plus every email you receive.
Managed Amazon SES
Outgoing through the built-in account, live the moment you sign up.
Mailbox storage
Metered across all of your team's mailboxes.
Enterprise
Dedicated infrastructure, priority support, volume pricing, and SLAs.
Standard pricing covers incoming mail and outgoing mail through your own providers. The managed Amazon SES rate applies only to sends through the built-in account.
Estimate
Estimate your monthly bill
Drag the sliders to your volume. The estimate updates as you go, with no sign-up and no email gate.
Estimated monthly cost
$15.20
Estimate only. Inbound mail rejected by your sender rules isn't billed.
Included
No per-seat fees. No per-mailbox fees. No surprises.
A free sending account
Every team gets a managed Amazon SES route on sign-up, capped at 50 emails a day. Raise it in one click.
Roles for people, keys for code
Add as many teammates as the work needs. Billing never counts seats, and scoped keys limit each service to its job.
Logs, metrics, and isolation
Delivery logs, usage metrics, and team-level isolation come with every account, never a higher tier you upgrade into.
How the bill is built
A simpler shape than tiered plans
Most email tools price by plan tier, then bill overage on top. A few charge by the inbox. Sendmux meters one thing: the email you actually move.
Price jumps at each tier, then overage stacks on top.
step → step → overageThe bill scales with inbox count, not the mail itself.
+inbox → +blockA single straight line: pay for the email that flows.
usage → bill, linearSendmux
- Pricing model
- Usage-based, per email
- Per-seat fees
- None
- Per-mailbox fees
- None
- Send and receive
- One rate, one bill
- Bring your own provider
- Any SMTP, weighted
Transactional email APIs
- Pricing model
- Tiered plans plus overage
- Per-seat fees
- Often gated to higher plans
- Per-mailbox fees
- Not applicable
- Send and receive
- Inbound often gated
- Bring your own provider
- Locked to their sending
Agent inbox providers
- Pricing model
- Per-inbox tiers
- Per-seat fees
- Bundled by tier
- Per-mailbox fees
- Inbox count sets the price
- Send and receive
- Inbox-native
- Bring your own provider
- Not supported
Based on public pricing pages, May 2026. Compared by category, not by named vendor.
Enterprise
Bigger volume, dedicated infrastructure
Past a few million emails a month, or when you need dedicated infrastructure, priority support, and a custom SLA, we'll price around your volume instead of a public rate. Same API, same usage model, no per-seat tax.
Pricing FAQ