Pricing & Limits
What an iMessage sender costs, what is included, sending pace, message limits and the errors you will meet
What Zernio charges
| Item | Cost |
|---|---|
| Dedicated sender | $200 per sender per month, phone or email alike. Billed as a flat monthly price at activation and on the 1st of each month while the sender is active; canceling stops it with the current month, with no proration or refund. |
| Connected account | The sender's imessage account counts as a connected account like any other platform, billed per day. |
| Messages | No per-message fee. Each sender allows unlimited messages up to 1,000 unique contacts a day. |
Included with every ordered number: SMS/RCS fallback with call forwarding, and the ability to message contacts who have not written first. A payment method on file is required to order or register a sender (402 otherwise), and the workspace has to be on usage-based billing (422 otherwise).
Limits
| Limit | Value |
|---|---|
| Text | 10,000 characters; longer texts are truncated |
| Attachments | 10 per message, public https URLs of at most 256 characters; large files take longer to reach the contact the first time |
| Voice notes | mp3, wav, m4a, caf or aac; dashboard recordings are transcoded |
| Edit window | 15 minutes after sending |
| Unsend window | 2 minutes after sending |
| New contacts | About one every 15 minutes per sender; the first message must not contain links, phone numbers, emails, prices or attachments |
| Contacts per day | 1,000 unique contacts per sender |
| Typing and read receipts | Only inside an active two-way conversation |
| Regions | US and UK numbers; instant activation depends on the provider's pool |
Common errors
| Status | Code | Meaning | Fix |
|---|---|---|---|
409 | recipient_opted_out | The contact opted out | Wait for their START or an opt-in link tap |
409 | recipient_must_message_first | The sender cannot start conversations (senders registered by handle without that add-on) | Share an opt-in link, or order a sender through Zernio |
429 | rate_limited | The sender hit its sending pace or its daily contact cap | Slow down, or spread contacts across senders |
400 | sender_unavailable | The sender is not active, or contactCard was sent with no contact card set | Check the sender's status, set the contact card |
400 | recipient_unreachable | The number is not a mobile or the contact blocked all messages | Verify the handle |
409 | edit_window_expired / unsend_window_expired | Apple's window has passed | Send a follow-up instead |
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Opt-in & Audience
Opt-in links and tracked links that open Messages on your sender, STOP and START handling, and the audience list
Telegram
Publish text, photos, videos, documents and albums to Telegram channels and groups with the Zernio API, edit published messages, and run DMs and bot commands from the inbox.