Quotas and plan limits
What each plan includes before any limit fires: send volume, overage ceiling, retention window, and spend cap, plus how the sending-domain cap works.
Your plan sets what you get before any limit fires: how many recipients you can reach per month, how far paid plans can overrun that into billed overage, how many sending domains your org may hold, and how long message history stays queryable. This page is the entitlement reference; when a send is actually refused, Rate limits and quotas covers the error types, headers, and retry guidance.
What each plan includes
| Plan | Price | Included recipients/mo | Overage per 1,000 |
|---|---|---|---|
| Free | $0 | 5,000 (hard stop) | None |
| Starter | $19/mo | 50,000 | $0.40 |
| Growth | $49/mo | 150,000 | $0.40 |
| Scale | $149/mo | 500,000 | $0.40 |
A dedicated IP is a plan-level entitlement rather than a volume limit, so it is not in the table above. See IP pools for which plans bundle one and what it costs elsewhere.
Marketing has its own allowance
The free plan's monthly allowance is split between transactional and marketing mail, and the two do not pool: exhausting one does not release the other. See Free plan allowances for the per-category split, and Email categories for how transactional and marketing mail are told apart.
The overage ceiling
Paid plans can send past their included volume into metered overage, up to a hard ceiling of 5× the included allowance. The free plan stops at its allowance instead of entering overage.
Retention
Message history, including its events, is only queryable back to your plan's retention floor.
| Plan | Retention |
|---|---|
| Free | 30 days |
| Starter | 30 days |
| Growth | 60 days |
| Scale | 90 days |
A message id past that window returns 404 not_found, the same response you'd get for an id that never existed or one that belongs to another org or environment. Analytics date ranges are clamped to the same floor rather than erroring; see Date windows and retention.
Domain limits
A plan caps how many sending domains your org may hold, and every domain counts toward that cap, pending ones included: an abandoned verification attempt still occupies a slot. Crossing the cap on POST /v1/domains returns 403 domain_limit_reached. Per-plan counts are not published in this documentation. See Adding a domain was refused if you hit it.
The spend cap
You can set an optional monthly cap on overage spend for your org. A send whose projected overage cost would cross it is refused rather than billed past the number you chose.
New accounts
A newly signed-up org sends live mail under an additional review ceiling while staff look at the account; see New accounts for what that returns and how long it lasts.
When a limit fires
For the error type each limit returns, the headers that come with it, and whether to retry, see Rate limits and quotas and the full table in Errors.