Engaging customers worldwide via SMS can get tricky, especially in regions with decreasing message quality and stringent regulations. Countries have different policies on what type of SMS traffic is permitted, and when it can be sent. Additionally, unreliable routes can lead to delays and dropped messages, making it increasingly challenging for businesses to interact with consumers.


Brands that use SMS for marketing campaigns or customer support depend on prompt, efficient deliveries. This is especially true for time-sensitive SMS one-time passwords (OTP) to verify users.


If customers don’t receive your messages in a timely manner—or aren’t receiving them at all—it will cause immediate frustration. This can cost your business big time.


So, what’s the solution? Here are the top four SMS delivery issues and how to overcome them.

1. Underperforming SMS routes


All routes are not created equal. Unfortunately, some are unreliable, resulting in delays and undelivered messages. When customers don’t receive your texts promptly, it can lower marketing ROI and negatively impact your customer support efforts.


How to fix it


By partnering with a dependable communications provider, you can rest assured that your messages will be always delivered efficiently.


Mitto’s AI proprietary routing platform analyzes and prioritizes traffic to ensure the fastest delivery speeds at the lowest costs possible. Reach your customers en masse without the headache of unpredictable SMS delivery.

2. Phone number problems


Your SMS campaign is only as strong as your contact list. If your list contains deactivated or invalid phone numbers, carriers might assume that you don’t have recipients’ permission to send them texts or that they’re not interested.


You might also be sending messages to landlines or roaming numbers. Customers may have their phones turned off or full memory cards, which prevents them from receiving new data. They might have also turned the “receive SMS messages” option off or own phones that aren’t capable of receiving texts.


In other instances, a recipient’s phone works just fine, but you forgot to include the international code or used the incorrect code format. Additionally, SMS messages sent in a different alphabet (i.e. Chinese or Arabic) can be marked as spam and not delivered.


Number portability may also be to blame. Customers might switch from one carrier to another while keeping their original phone number. The new carrier might assume your texts are spam and block them.


How to fix it


Ensure your contact list contains only valid, active numbers of customers who are still opted-in to your SMS program. Regularly cleanse your data to get rid of deactivated and invalid phone numbers.


Mitto’s Number Lookup reveals key insights into phone numbers to help you know if they are valid, carrier checks, international number formatting, portability status, and line types.

3. Local regulation restrictions


Depending on the country, local restrictions might be interfering with SMS deliverability. Some countries only allow marketing messages to be sent from 8 a.m. to 8:30 p.m. on workdays. If you send texts outside of this window, they won’t be delivered.


Other countries restrict SMS length. In most regions, including the U.S., the maximum length for SMS messages is 160 characters. In other markets, like Brazil, carrier networks only support texts of up to 157 characters.


How to fix it


Mitto’s Campaigns platform lets you easily craft and manage your SMS campaigns. Build your campaign now, and schedule it at specific times to bypass local restrictions. Ensure your texts always meet the required character counts for the countries you send them to.

4. Missing failover


Failover systems enable businesses to switch from one communication channel to another if the primary channel fails. If these backup channels are missing, customers won’t receive your messages.


Your brand must have a reliable and robust messaging stack to deliver best-in-class service and ensure customers receive all communications.


How to fix it


Mitto provides our clients with dependable secondary channels if SMS messages fail to go through, including SMS to WhatsApp and SMS to voice. This guarantees customers receive your communications, even if the primary channel isn’t working.

Overcome SMS delivery issues with Mitto


Mitto guarantees the best SMS deliverability at the most competitive rates. Our proprietary routing system tests SMS messages to real devices throughout all customer destination countries. The texts are also paired with software that sends 24/7 feedback, allowing our AI routing engine to select the fastest and most cost-effective routes. Additionally, Mitto’s long-term relationships with global operators ensure brands reach their customers, no matter where they’re located.

Want to see how our cutting-edge routing platform, world-class SMS API solutions, and communications tools can transform how your business engages customers? Contact Mitto today.