Sendmux

Email API pricing, metered by usage

Pay for the email that flows and the storage you use, not seats, mailboxes, or tiers. Start free, then move to Pro when you need more room.

Free to start. No credit card required.

usage meter metering
1,000,000accepted recipients
$507.00billed this month
Example · 1,000,000 accepted recipients at $0.50 / 1,000 = $500, plus the $7 Pro team feeseats · mailboxes · resource counts not metered
$0/ team · mo
Free
$7/ team · mo + usage
Pro
Custom
Enterprise

Plans

Free, Pro, Enterprise

Start with fixed Free limits. Pro adds prepaid usage and credit top-ups, with unlimited plan-level resource counts.

PlanFree$0/ team · mo

Fixed limits with $1 usage credit.

Production planPro$7/ team · mo + usage

Prepaid usage on top of the team fee.

EnterpriseCustom

Pricing shaped around your volume.

Resources
Active teams owned1Unlimited*Per teamContract
Domains1Unlimited*Contract
Mailboxes2Unlimited*Contract
Connected sending accounts1Unlimited*Contract
Webhooks1Unlimited*Contract
Credentials2Unlimited*Contract
Team membersOwner onlyUnlimited*Contract
Usage and billing
Included usage credit$1PrepaidContract
Manual credit top-upsUnavailableIncludedIncluded
Automatic top-upsUnavailableIncludedIncluded
Postpaid usageUnavailableUnavailableIncluded
Per-seat and per-mailbox feesNoneNoneNone
Volume and support
InboundWithin $1 creditUnlimited*Contract
Connected outboundWithin shared 50 per dayUnlimited*Contract
Managed sending2 per hourWithin shared 50 per dayUnlimited*Contract
Higher managed daily limits by reviewUnavailableIncludedIncluded
Dedicated infrastructureUnavailableUnavailableIncluded
Priority support and custom SLAsUnavailableUnavailableIncluded
Start FreeUpgrade to ProContact Sales

* Unlimited means no monthly usage allowance or plan-level resource count. Provider quotas, available credit, fair usage, abuse controls, and operational safety limits still apply. Higher managed daily limits are available by review. The Free cap is 50 provider-accepted recipients per UTC day across all outbound routes. Each owner can have one active Free team. You can't top up Free credit, so upgrade to Pro when you reach a fixed limit. Each accepted To, CC, and BCC recipient counts separately. Rejected recipients are not billed.

Usage pricing

Four rates, metered per event

Usage sits on top of the Pro team fee. We show rates per 1,000 for easy maths. Billing counts every event, so nothing rounds up.

Billed dimensionRate

Connected outbound

Send through your own connected providers.

$0.50/ 1,000$0.000500 per provider-accepted recipient

Managed sending

Send through the built-in managed account.

$0.75/ 1,000$0.000750 per provider-accepted recipient

Inbound

Each mailbox delivery counts once.

$0.50/ 1,000$0.000500 per distinct mailbox delivery

Storage

Metered across your team's mailboxes.

$0.02/ GB · moper decimal GB-month

Per event, never in blocks of 1,000

Send 1,400 accepted recipients. You pay for 1,400, not the next block up.

Priced in blocks of 1,000

1,400 sent → 2,000 billed

Sendmux, per event

1,400 sent → 1,400 billed

Usage is billed per event, never in blocks of 1,000.Each accepted To, CC, and BCC recipient counts separately.Rejected outbound recipients are not charged.One inbound email in two mailboxes counts as two deliveries.

Estimate

Estimate your monthly bill

Drag the sliders to your volume. The estimate includes the $7 Pro team fee and updates as you go, with no sign-up or email gate.

100,000

Each accepted To, CC, and BCC recipient counts separately. Rejected addresses are free. $0.50 / 1,000.

0

Accepted recipients through the built-in account at $0.75 / 1,000

20,000

One count per mailbox the email lands in at $0.50 / 1,000

10 GB

Metered across all team mailboxes at $0.02 / GB · mo

Estimated monthly cost · Pro

$67.20

Pro team fee1 team × $7.00$7.00
Outbound100,000 × $0.50 / 1k$50.00
Managed sending0 × $0.75 / 1k$0.00
Inbound20,000 × $0.50 / 1k$10.00
Storage10 GB × $0.02$0.20
1M connected = $507 / mo1M managed = $757 / mo

Estimate only. Rejected outbound recipients aren't charged, and billing counts each event rather than blocks of 1,000.

Included

No per-seat fees. No per-mailbox fees. No plan-level resource caps.

A Free team, fully mapped

Two mailboxes, one domain, $1 usage credit, and 50 provider-accepted recipients a day. Limits are fixed. Upgrade to Pro when you reach one.

Free daily cap50 / day

Roles for people, keys for code

Add the team members and mailboxes your work requires. The Pro plan has unlimited plan-level resource counts, so you don't have to worry about extra fees for each seat or mailbox.

3 seats added$0.00

Top-ups and safety controls

Pro supports manual and automatic credit top-ups. Managed sending is usage-based, with fair usage and operational safety limits. Higher daily limits are available by review.

On every Pro team$0.00
manual top-ups automatic top-ups provider quotas

Enterprise

Bigger volume, dedicated infrastructure

When you need dedicated infrastructure, priority support, volume pricing, or a custom SLA, we'll price around your volume instead of the public rate. Same API, same usage model, and no per-seat or per-mailbox fees.

Your rateCustom
Dedicated infrastructurePriority supportVolume pricingCustom SLAs

Pricing FAQ

Pricing questions

EMAIL API FOR AI AGENTS

Your agents need email. Start sending in five minutes.

One API for agent inboxes, BYO outbound routing, and everything in between. Free to start, scales to millions.