SMS API | Frequently Asked Questions

Looking for an answer to a specific question? We've collected the most frequently asked questions about the SMS API for you. 

If any questions arise while reading, you can contact us under


Frequently Asked Questions

What is a 'Source IP Address'?

The ‘Source IP Address’ is your server’s IP address. We need it to whitelist your IP Address in our system. This is the IP address from which you’ll be able to send SMS to our server. If you don’t know your IP address, ask your IT personnel or developer.

Can I add multiple 'Source IP Address'?

Yes. For each new account, you can add up to 2 new IP addresses. If you feel you need to add more than 2, just get in touch with us by writing us a ticket from your Support section.

What is the ‘Respond back URL’?

For each SMS sent, our system provides you with an acknowledgement receipt. Enter the URL to which this shall be sent.

What does the acknowledgement receipt look like?

You have the ability to query the status of each message. Please view our Tech Docs to learn more about the acknowledgement receipt: content/sms/rest_api/send_sms_messages/connetion_ steps/step_3_query_the_status_of_a_sent_sms_message_ notification.html

How soon can I start using the new SMS one-way account?

Instantly! You will be able to start using your SMS one-way account right away after you receive the email with your credentials.

What is the difference between the RESTful API and SMPP / SMPP over SSL?

Our RESTful API and SMPP offer you similar qualities. For most enterprises, a RESTful API is more easily integrated. The SMPP connection requires the implementation of the SMPP protocol. SMPP is usually suggested for larger enterprises and specific use cases. If you’re not sure which protocol fits your use case best, we’re here to help you! Just get in touch with our Customer Success Team.

How much does it cost to send SMS?

The cost depends on which country and operator you’re sending the SMS to. Head to the Pricing & Coverage section for more information about prices. You can find it under ‘Finance’ in the main navigation while logged in to your tyntec account. If you don’t see any prices yet, check out the pricing section for SMS on our public website.

Where can I find the technical documentation for SMS one-way?

You can find the technical documentation including how to set up SMS one-way in our Tech Docs under:

What number types can I use as a Sender ID for my SMS one-way account?

The SenderID can be sent in the format of an international or national number, short code and alphanumeric.

Why can’t I see any prices on the  ‘Pricing & Coverage’ page?

If you haven’t set up an SMS account yet, you will see a table with a note saying ‘No data available.’ Add your first SMS account to view the prices for your account. You can always view the general pricing & coverage for SMS on our public website here:

Is there an API for the prices that we can  integrate into our system?

Yes. We offer an easy-to-use API for the Pricing & Coverage. Head over to our Tech Docs to see how you can integrate it: and_pricing