Both are email APIs built for AI agents rather than retrofitted from a marketing tool. The difference is the pricing model: AgentMail sells a monthly tier with inboxes as a line item, and we sell metered credit with inboxes free. Here is the comparison with real numbers, and the cases where AgentMail is the better pick.
| AgenticBoxes | AgentMail | |
|---|---|---|
| Inboxes | Unlimited, free, no per-inbox fee | 3 free, then $2 per inbox per month on the Developer tier |
| Inbound to your webhook | Yes, pushed the moment mail lands | Yes |
| Agent signs itself up | Yes, two API calls, no card | Account signup is the usual human flow |
| Agent pays for itself | Yes, Stripe Link agent wallet with owner-set caps, or per-charge approval on your phone | Not offered |
| Per-agent sending reputation | Yes, with its own suppression list per account | Not published |
| Price per 1,000 messages | $0.40 at Founders’ Pricing | Bundled into the monthly tier |
| Emails a month | AgentMail | AgenticBoxes |
|---|---|---|
| 3,000 | $0 (free tier, 3 inboxes) | $1.20 — and the first 250 are free |
| 10,000 | $20 (Developer) | $4 |
| 40,000 | $20 (Developer) | $16 |
| 10,000 + 50 inboxes | $20 + $94 inbox fees = $114 | $4 — inboxes are free |
AgenticBoxes figures use Founders’ Pricing at $0.0004 per message, which is the rate shown on our pricing page. Inboxes are free and unlimited on every account.
If you want a flat monthly bill you can forecast exactly, a tier is easier to reason about than metered credit — you know the number before the month starts. If you only ever need a handful of inboxes and send under 3,000 messages a month, their free tier costs nothing and so does ours below 250 messages; past that you are comparing $0 against $1.20, which is not a reason to switch. And they have been building in public for longer, so if a specific integration of theirs is already working for you, inertia is a real argument.
The honest summary: we are cheaper once you need many inboxes or more than a few thousand messages, and we are the only one of the two where the agent can sign up and pay on its own. Below that, the difference is small enough that it should not decide anything.
At volume and at inbox count, yes. 10,000 emails a month is $4 at Founders' Pricing against AgentMail's $20 Developer tier, and 50 inboxes is free here against $94 a month in per-inbox fees there. Below roughly 3,000 emails a month with a few inboxes, AgentMail's free tier costs nothing and the difference does not matter.
On AgenticBoxes, yes. Two API calls create an account with 250 free messages and no card. For payment the owner either approves each top-up from a Link notification on their phone, or saves a card once with spending caps the agent can never raise. AgentMail does not offer agent self-signup or agent payment.
Not here. Inboxes are free and unlimited on every AgenticBoxes account, so an agent can create github@, billing@ and one box per customer without the cost changing. AgentMail includes 3 inboxes and charges $2 per month for each additional one on the Developer tier.
Real email. Messages are delivered over SMTP through AWS SES to any address on the internet, with DKIM, SPF and DMARC set up for your domain. Inbound is real mail from real senders, pushed to your webhook.
250 free messages, no card. Two API calls to a working inbox.
Get an API key, free → See full pricing
Pricing as of October 2026, taken from each provider's public pricing page. If something here is out of date or wrong, tell us at support@agenticboxes.email and we will correct it.