Limits and allowances
Plan API sending around recipient counts, monthly allowances, and daily caps.
Plan allowances
These are the standard plan allowances introduced in web 0.40.0. Your organization can have a custom allowance; the console’s Developers > Sending page shows the effective figures.
| Plan | Monthly recipients | Daily recipients |
|---|---|---|
| Solo founder | 12,500 | 1,250 |
| Duo | 25,000 | 2,500 |
| Small team | 62,500 | 6,250 |
| Growing business | 156,250 | 15,625 |
| Established company | 375,000 | 37,500 |
| Enterprise | Agreed per organization | Agreed per organization |
The daily cap is one tenth of the monthly allowance, rounded down, with a minimum of one. An explicit daily override takes precedence. Enterprise is agreed per organization. Until a monthly figure or override is set, the fallback is 1,000 recipients a day with no monthly cap.
How counting works
Usage is counted per unique, non-suppressed recipient when a live message is queued, not when delivered. One accepted message to three active recipients consumes three emails. Addresses repeated across To, Cc and Bcc are deduplicated.
The monthly window is the UTC calendar month. The daily window resets at midnight UTC. Monthly usage resets at the start of the next UTC month. All keys in the organization share these allowances.
Test keys and mail people send from their own mailboxes never count toward the API allowance. Suppressed recipients do not count. A later sending failure or bounce does not refund a queued recipient.
At the limit
If the non-suppressed recipients do not fit the remaining monthly allowance or daily cap, that message is refused with ErrorCode 405, HTTP 422. No partial message is queued merely to use the remaining capacity.
The monthly refusal includes usage, allowance and the reset date. A daily refusal includes usage, cap and the midnight UTC reset. Batch entries are evaluated in order, so earlier messages may be accepted and later ones refused.
Organization admins receive notices when monthly usage reaches 80% and 100%. Each threshold is claimed once per organization per UTC month.
Request more
An organization admin opens Developers > Sending in the console and selects Request more. If you do not have admin access, give an admin your expected recipients per month, peak daily volume and reason for the increase. Approval is not automatic.
Technical limits
| Limit | Value |
|---|---|
| Recipients per message | 50 unique addresses across To, Cc and Bcc |
| Messages per batch | 500 |
| Bodies and decoded attachments | 10,485,760 bytes (10 MiB) |
| API single-send request body | 15,728,640 bytes (15 MiB) |
| API batch request body | 52,428,800 bytes (50 MiB), with a 32 MB outer proxy cap in the managed stack |
| Requests per minute per key | 120 |
| Activity page size | 1 to 500; count + offset at most 10,000 |
| Daily cap rule | Monthly allowance divided by 10, rounded down, minimum 1. An explicit daily override takes precedence. |
| No monthly figure or overrides | 1,000 per day |
The message-size limit counts UTF-8 body bytes and decoded attachment bytes. HTTP body limits count the encoded JSON, including base64 expansion. The managed proxy’s outer limit can therefore refuse a request before the API checks an individual message.
See Send an email for subject, tag, metadata and header bounds.