OTP Inbox Free vs Premium: Mailboxes, Retention, Domains, and Costs

By OTPINB Team · Published 2026-11-03 · Reviewed 2026-11-03

Premium is useful when your temporary-mail workflow needs more mailboxes, more new addresses or more time to revisit messages. Free is a starting point when your active tasks fit within the smaller limits.

Both plans use the same public-access model for newly created configured mailboxes. Premium does not buy a private inbox, and it does not provide unlimited outgoing email. Sending Credits are purchased and used separately.

Compare the current mailbox rules

Guest access has a separate limit: 5 mailbox creations per network/IP in a rolling 24 hours. People sharing a network can share that allowance. Signing in gives you account-based management; it does not erase creation history or bypass other checks.

The held-mailbox limit and the creation limit are separate. A Free account with room for another mailbox can still have used all 10 creations in its rolling window. Deleting a mailbox does not immediately restore a creation attempt.

Monthly and yearly have the same benefits

The current catalog offers monthly Premium for $6.99 with a 30-day term and yearly Premium for $58.72 with a 365-day term. The yearly total is about 30% below twelve monthly purchases. Prices and term lengths should be checked on the live Pricing page before payment.

Both choices provide the same Premium mailbox benefits while active. Pick the term based on how long you expect to use the workspace, rather than expecting a different sending allowance from the yearly option.

Membership is prepaid: you purchase a term using your Balance, and it does not automatically renew through a saved card. Check the expiry shown in your account and choose whether to buy another term when needed.

Balance, Credits and Premium are different purchases

Balance is your account's USD spending balance. A NOWPayments crypto top-up funds it after the payment is verified and settled by the backend. Reaching a return page alone is not proof that a deposit has been credited.

Credits pay for sending email. Each new mailbox starts with 1 gift sending Credit. Each send is to one recipient and uses 1 Credit. Sending separately to two recipients requires two send operations and 2 Credits. The mailbox gift is used first; shared account Credits can be used afterward with your explicit selection.

Premium buys the membership term and its mailbox benefits. It does not turn USD Balance into sending Credits automatically, and renewal does not reset a daily sending allowance.

Free and Premium users can buy shared Credits after signing in. Custom quantities currently cost $1 per 100 Credits. The four quantity packages remain separate offers with their own prices and quantities, so compare them on Pricing rather than applying the custom rate to every package.

What a top-up does

1. Sign in and open Top up.
2. Enter the USD amount. The current minimum is $5.
3. Create the payment request and use the hosted NOWPayments checkout.
4. Return to the wallet status view and wait for verified settlement.
5. Use the credited Balance to buy the Premium term or Credits you selected.

Crypto fees, supported payment assets and the final credited amount should be checked in the actual payment flow. Do not assume that every deposit arrives instantly or that paying a displayed invoice automatically completes a separate membership purchase.

Never send a wallet API key, payment secret or password to support. If a status needs investigation, use the site's authenticated order/status controls and the legitimate support channel.

Choose Premium for a specific workflow

If you repeatedly need more than 5 bound mailboxes, Premium provides room to separate test scenarios without replacing the address list after each small batch. Its larger rolling creation allowance helps when your authorized testing requires more new recipients.

Longer retention helps when a test result needs review later. It does not preserve the sender's code validity or make a public mailbox confidential. Domain availability also follows the operator's configuration; membership does not let you attach any domain you own through an assumed custom-domain feature.

Do not infer unlisted storage, simultaneous-reception or API guarantees from the mailbox count. Buy for the benefits currently described by the product, not for features that may have appeared in an earlier proposal.

A practical way to decide

Start Free with one low-risk workflow. If you hit a mailbox or retention constraint, compare the Premium term with the task's duration. If the only constraint is sending from an existing address, additional Credits may be the relevant purchase instead.

For a larger workflow, read how to organize multiple temporary inboxes. Then compare the current plans with your actual capacity and retention needs in mind.