HTML version: https://cooperemail.com/pricing

- [Home](/)
- › Pricing

Cooper Email is an email API that gives each AI agent its own inbox. [Free is $0 and includes 5 inboxes and 5,000 emails a month](/pricing).

Updated 2026-10-18

# Cooper Email costs $0, $12, or $99 a month.

More inbox and more mail than AgentMail, at a lower price.

Free is $0 with 5 inboxes and 5,000 emails a month. Starter is $12 with 25 inboxes, 25,000 emails, and 15 custom domains. Pro is $99 with 300 inboxes, 250,000 emails, and 200 domains.

Start here

## Free

$0

- 5 inboxes
- 5,000 emails/month
- no daily cap
- Custom domain not included
- 5 GB storage
- Search, webhooks, MCP, HTML and attachments
Start with the API

Most agents

## Starter

$12/mo

- 25 inboxes
- 25,000 emails/month
- no daily cap
- 15 custom domains
- 25 GB storage
- Search, webhooks, MCP, HTML and attachments

POST /api/v1/billing/checkout {"plan":"starter"}

Fleet

## Pro

$99/mo

- 300 inboxes
- 250,000 emails/month
- no daily cap
- 200 custom domains
- 100 GB storage
- Search, webhooks, MCP, HTML and attachments

POST /api/v1/billing/checkout {"plan":"pro"}

## Your agent gets a phone number

Starter and Pro agents can buy a US local number through the API or MCP and receive SMS on that inbox. Each billable number is $3 a month. Pro includes 3 numbers.

### What works today

- Buy a US number with POST /api/v1/inboxes/{id}/phone-number {"area_code":"415"} or the MCP tool cooper_provision_phone_number. A verified owner is required (HTTP 409 owner_required). Idempotency-Key is supported. GET reads the number and DELETE releases it.
- Inbound texts are stored on the inbox as messages with channel sms. Cooper sends a message.received webhook. otp_candidates lists codes found in the text.
- Wait with the MCP tool cooper_wait_for_sms (default 20 seconds, maximum 25). GET /api/v1/inboxes/{id}/events?types=message.received&wait=25 waits for the next received message on the inbox, email or SMS. It does not filter to SMS.
- STOP, STOPALL, UNSUBSCRIBE, CANCEL, END, QUIT, OPTOUT, and REVOKE opt that sender out. START, YES, or UNSTOP clears the opt-out. A send to an opted-out recipient returns HTTP 409 recipient_opted_out.
- Price: $3 a month per billable number on Starter and Pro, with 100 segments on that number.

- Phone number: Free includes none.
- Phone number: up to 3 US numbers, each $3 a month with 100 segments. None are included.
- Phone number: 3 US numbers and 1,500 segments included, up to 25 numbers. Each extra number is $3 a month with 100 segments.
An OTP or 2FA text arrives on the agent’s number, is stored on the inbox, and can wake the agent by webhook or wait.

[Phone numbers](/phone) · [SMS docs](/docs/sms) · [Owner SMS alerts](/sms-opt-in)

## Who each plan is for

[Use cases by plan](/use-cases) names the personas. The short version is below.

No public URL? Use /wait, /wait-for-code, or SSE instead of a webhook.

## Free: one builder, a few agents

Free is for a builder who wants a few agents to have their own address, without a card or a custom domain.

- Personal agent address
- Signup + OTP codes
- Approve before send

5 inboxes · 5,000 emails/mo · 0 domains

[See all use cases →](/use-cases#free)

## Starter: a production agent on your domain

Starter is for a small team running one production agent from its own domain.

- support@ on your domain
- Invoice & receipt inbox
- Test inbox per CI run

25 inboxes · 25k emails/mo · 15 domains · up to 3 US numbers

[See all use cases →](/use-cases#starter)

## Pro: an inbox for every customer or agent

Pro is for products and fleets that give every customer or agent its own inbox.

- Inbox per customer (workspaces)
- Agent fleets
- Outbound across many domains

300 inboxes · 250k emails/mo · 200 domains · 3 US numbers included

[See all use cases →](/use-cases#pro)

Starter and Pro can buy a US number and receive texts.

## Add-ons

Starter and Pro can add capacity on the subscription they already have. $1 per extra inbox / month, $1 per extra custom domain / month, $1 per 1,000 extra emails / month. POST /api/v1/billing/addons with {"inboxes":1}, {"domains":1}, or {"email_packs":1} replaces that quantity, from 0 to 100. An increase is invoiced immediately, and the cap rises only after Stripe confirms payment. A decrease is not credited and cannot drop below live usage. The MCP tool is cooper_set_addons. Free stays at the included cap and that call returns HTTP 402. AgentMail’s published unit is $2 ([pay as you go](https://www.agentmail.to/blog/pay-as-you-go), 2026-10-10).

## Side by side with AgentMail

|  | AgentMail | Cooper |
| --- | --- | --- |
| Free | $0 · 3 inboxes · 3,000/mo · 100/day · 0 domains | $0 · 5 inboxes · 5,000/mo · no daily cap · 0 domains |
| Entry paid | Developer $20/mo · 10 inboxes · 10,000/mo · 10 domains | Starter $12/mo · 25 inboxes · 25,000/mo · 15 domains |
| Team paid | Startup $200/mo · 150 inboxes · 150,000/mo · 150 domains · SOC 2 report | Pro $99/mo · 300 inboxes · 250,000/mo · 200 domains · SOC 2 not included |
| Overage unit | $2 | $1 |

AgentMail figures are their public list, retrieved 2026-10-10 from [AgentMail pricing](https://www.agentmail.to/pricing) , [AgentMail pay as you go](https://www.agentmail.to/blog/pay-as-you-go) , [AgentMail rate limits](https://www.agentmail.to/docs/knowledge-base/rate-limits) . AgentMail Startup includes a SOC 2 report. Cooper does not have a SOC 2 report. Startup monthly sends are stated as 150,000 in AgentMail’s pay-as-you-go post and rate-limits doc. The pricing page leaves Emails/month blank and lists 15,000 emails/day. Enterprise on both products is custom — email ops@avatar33.com. Full write-up: [/compare/agentmail](/compare/agentmail).

## SMS

A number is $3/month and includes 100 segments. Starter starts at zero included numbers and caps at 3. Pro includes 3 numbers and 1,500 segments, and caps at 25. Numbers past the included three are $3/month and add 100 segments each. Extra segments are $10 per 500. Numbers are added to your Cooper subscription in Stripe and prorated; releasing a number takes it off. Segment packs are invoiced immediately on an increase, and a decrease is not credited.

A number can receive SMS. Inbound texts are stored on the inbox, with webhooks and wait. Account notification texts are sent on Avatar 8 LLC's verified campaign. POST /api/v1/inboxes/{id}/sms returns HTTP 409 outbound_not_registered. Details are on [/docs/sms](/docs/sms).

|  | Free | Starter | Pro |
| --- | --- | --- | --- |
| Numbers | None | Up to 3 at $3/mo each | 3 included, up to 25 |
| Segments | None | 100 per number / month | 1,500 included, plus 100 per extra number |
| Extra segments | — | $10 per 500 | $10 per 500 |

## Voice

Each number includes 30 voice minutes a month on Starter. Pro includes 300 minutes, plus 30 for each number past the included three. Free has no voice minutes. Extra minutes are $10 per 250. POST /api/v1/billing/voice-minutes returns HTTP 404 and does not call Stripe.

A caller hears a short greeting, then leaves a voicemail of at most 120 seconds. Once the allowance is used, inbound stays voicemail-only and the recording cap is 60 seconds. Outbound calls past the allowance return HTTP 402. Calls are limited to US and Canada numbers, and an account can place at most 100 calls per day. Details are on [/docs/phone](/docs/phone).

|  | Free | Starter | Pro |
| --- | --- | --- | --- |
| Minutes | None | 30 per number / month | 300 included, plus 30 per extra number |
| Extra minutes | — | $10 per 250 | $10 per 250 |