Posthaste is a transactional email API for developers — password resets, receipts, verification codes. We run our own mail servers, so we sign your email, deliver it straight to the recipient’s server, and hand you every response it gave back.
How it works
Most providers show you a status. We show you the conversation that produced it.
Unverified domain, suppressed recipient, header injection — refused straight away with a reason, not queued and quietly failed an hour later.
Every message is signed with your own domain key, so receivers can prove it genuinely came from you.
Straight to the recipient's mail server over an encrypted connection. Nobody sits in the middle taking a cut.
Delivered, delayed or refused — you get the receiving server's own words, kept on a record you can verify.
Status
No ambiguity, no “sent” that means nothing. Each state is a fact we can show you the evidence for.
The receiving server accepted it and told us so. We keep what it said.
Refused permanently. The address is suppressed immediately, so it is never tried again.
A temporary refusal. We retry on a backoff, and we do not suppress — that would strand a working address forever.
Refused before we sent anything, because this address has already bounced or complained.
Features
Every hop, every response code, every retry reason — on a tamper-evident record you can check yourself.
Each message carries a unique return path, so a bounce is tied to the exact send rather than guessed at.
Dead addresses are blocked instantly. Temporary failures never are — that would make a working address unreachable forever.
Events pushed the moment they happen, signed and timestamped so a captured request cannot be replayed.
Send the same request twice by accident and we deliver once. Idempotency is built in, not bolted on.
We tell you exactly which record is wrong, and warn you before you overwrite something that would break your other mail.
The difference
Most providers are a nicer interface on top of infrastructure they rent. That is the reason they can only ever show you a status.
The conversation that decides whether your mail arrives happens on infrastructure your provider rents. They cannot show you what they cannot see.
One hop, and it is ours end to end. That is why we can hand you what the receiving server actually said instead of a status we inferred.
Pricing
No per-seat charges, no charge for webhooks, no charge for keeping your own records.
Dedicated IP +$49/mo Your own sending address, warmed up with guidance rather than dropped straight into production volume. Worth it once your reputation is worth protecting on its own.
Launch pricing, and honest about the stage: Posthaste is in private testing while we build sending reputation on a new IP. If we cannot deliver your mail, you should not be paying for it — so the free tier stays free and paid plans start when we have proved it.
Questions
Free for 5,000 emails a month. One DNS record to set up. No card needed.
Start sending free