Can a new account send SMS immediately?

No. New Text King API keys start in review. Live sending opens after the business identity, use case, sample messages, and consent path are reviewed.

What messages fit the API?

Text King is built for operational business SMS such as appointment reminders, order updates, account alerts, and customer support follow-ups.

How are opt-outs handled?

Recipients can reply with common opt-out words such as STOP or UNSUBSCRIBE. Text King records the opt-out and blocks future sends for that recipient under the account.

Approved sender API

Business SMS API for consent-based customer messages

Text King is a business SMS API for teams that need prepaid credits, API keys, delivery status checks, and a review step before live traffic. It fits operational messages where the recipient has already opted in.

Buy SMS credits Review SMS consent

What this business SMS API includes

The API surface is intentionally small. You can create or refill a paid key, send a single consent-based message, check quota, and check delivery status. That is enough for appointment reminders, pickup alerts, account notices, and support follow-ups without pulling a whole marketing platform into the stack.

Send endpoint

POST /v1/messages accepts one approved business SMS request.

Credits

One SMS segment spends one prepaid credit.

Quota

GET /quota/:key returns credits and account review status.

Status

GET /status/:textId returns delivery state for a sent message.

Who should use it?

Text King is a fit when you already have a legitimate customer relationship and a clear consent path. A clinic can remind patients about tomorrow's appointment. A repair shop can say a device is ready for pickup. A SaaS product can send account alerts to users who asked for SMS notifications.

It is not built for cold outreach, scraped lists, hidden sender identity, or emergency alerts. Those uses are blocked because they create risk for recipients, carriers, and every approved sender sharing the channel.

What happens before live sending?

New keys start pending. Text King reviews the sender identity, sample content, message purpose, and opt-in path before enabling live sends. That review step is slower than an open test key, but it keeps the product honest about carrier and recipient expectations.

The public consent page explains the required disclosure language. For carrier context, Twilio's A2P 10DLC compliance documentation is a useful reference for why business texting needs registration and review.

How do opt-outs work?

Recipients can revoke consent by replying STOP, QUIT, END, CANCEL, UNSUBSCRIBE, OPT OUT, or REVOKE. Text King stores the opt-out and blocks future sends to that recipient for the account. The API is designed for senders who want those controls handled in the product instead of bolted on later.

You should still keep your own opt-in records. The FCC's guide on unwanted calls and texts is a plain-English place to start if your team is new to SMS consent.

Related Text King pages

Textbelt alternativeCompare prepaid API keys with Text King's review-first account surface.Appointment reminder SMS APISee how reminder messages fit consent-based operational texting.SMS compliance policyReview allowed messages, opt-outs, and prohibited use cases.

Start with a reviewed API key

Buy credits, submit your use case, and keep the first send boring: sender name, message purpose, useful customer information, and a clear STOP path.

Create an API key