10 Reasons Your Text Messages Aren’t Delivering and How to Fix Them

Seeing a red “failed to send” exclamation point next to your text messages?

Like a fingerprint at a crime scene, that pesky punctuation is a clue that your text message hasn’t been delivered to its recipient. Unfortunately, it doesn’t tell you why the message wasn’t sent, so you have to play detective to get to the bottom of it.

Fortunately for you, I love a good mystery. I’ll be the Watson to your Holmes and give some possible explanations for why your message isn’t sending. 

Why Aren’t My Text Messages Delivering?

The first step in this investigation is to eliminate possible reasons why your messages aren’t delivering. Let’s dig into the 11 most common reasons SMS campaigns don’t make it to their destination.

1. Your Number Isn’t Verified by Carriers for Mass Texting

App-to-person (A2P) platforms (like ours) are used by legitimate businesses who want to send and manage texts to their contacts. But like most good things, it can become a bad thing if it falls into the wrong hands. 

To combat fraud, spam, and other illegal activities from their networks, wireless carriers require businesses to verify their phone numbers.

If you haven’t registered your 10-digit number with The Campaign Registry or verified your toll-free number with wireless carriers yet, your messages may be limited. Check out our guides to learn more about toll-free number verification and 10-digit number registration, and chat with our team using the blue button in the bottom right corner for help.

→ Need help choosing a number? Check out our guide to SMS number types.

1. You’re Using the Wrong Messaging Type

If you’re trying to send SMS campaigns from a personal phone number, you may experience carrier filtering. This is known as peer-to-peer (P2P) messaging, which is traditional text messaging from one individual to another. 

When you text on your cell phone to a friend or acquaintance, you are using P2P messaging.

A2P messages, like I mentioned earlier, are more commonly used by businesses or organizations for marketing purposes. They require the sender to be registered with an SMS application that allows them to send out mass messages to hundreds or thousands of recipients at once.

If you are attempting to use A2P-style messaging, you’ll need to have the right type of phone number, which you receive when signing up for a text messaging service. 

Without this, your traditional phone number will be flagged when sending out mass messages and your messages won’t be delivered. 

2. Your Message Could Be Considered to Contain Illegal Content

If you’re sending text messages containing adult content, drug references, or any kind of criminal activity, your messages will be blocked by the receiving carrier.

That’s because the Cellular Telecommunications and Internet Association (CTIA) — a regulatory body that enforces guidelines for SMS messages — prohibits messages with SHAFT content — sex, hate speech, alcohol, firearms, and tobacco. 

The CTIA also prohibits messages that contain:

• Depictions or endorsements of violence 
• Adult or otherwise inappropriate content 
• Profanity 

If your business sells alcohol, you can send SMS campaigns to advertise events like happy hours or drink specials as long as you have an age verification method in place.

3. You’re Sending Too Many Text Messages

If you’re sending too many text messages, your messages could be caught in the spam filter. Depending on the phone you’re using, there are compliance guidelines as to how many messages a user can send.

While there’s no hard-and-fast rule for how many messages you can send to each contact, you can consider what would be a reasonable amount of messages for your industry or business type. 

For instance, someone using texts to message their employees about available shifts or schedule changes may send dozens of messages a week to each contact, while a retail store may only send a promotional message once a week. 

4. Your Links Look Suspicious

Some scammers use link shorteners to disguise phishing links. Carriers may filter messages with links that look shady, including those that are shortened by third-party apps.

If you’re sending texts with our platform, you can shorten links from the message composer so you don’t have to use a separate link shortener. 

5. Your Mass Texting Platform Is Prohibited in the Recipient’s Country

Depending on which country you are receiving or sending messages from, local regulations may restrict the sending of SMS messages to prevent spam.

For example, in some countries, messages notated as ‘marketing’ can be sent only during workdays and in a specific time window. If sent outside this window, your message will not be delivered. 

If you use an A2P service, you can schedule messages and send them out automatically at specific times to help bypass these restrictions.

6. Your Contact List Has Invalid Phone Numbers

If your contact list is littered with invalid or deactivated numbers, it may signal to carriers that you don’t have their permission or they’re no longer interested in your texts.

Depending on which SMS service you use, you may need to submit your contact list to a verification service to identify invalid or deactivated numbers. 

SimpleTexting has self-cleaning lists that do this for you so you won’t unknowingly send multiple messages to invalid phone numbers.

There are two ways to see which of your contacts are invalid.

1. In your inbox, you’ll see an Invalid tag in the contact’s details.

2. From the Contacts tab, you’ll see the Invalid section on the far-right side of the screen.

It may be hard to believe, but there’s a chance your undelivered messages were sent to a landline. 

Although far less common in recent years, people still do have landline phones, so there is a possibility the phone number is simply not capable of receiving text messages.

7. The Contact Doesn’t Want to Receive Your Text Messages Anymore

Sometimes people change their minds about subscribing to texting lists. They may:

• Block the phone number.
• Report the number as spam to their wireless carrier.
• Unsubscribe (eg. “Text STOP to stop receiving these messages”) 

Either way, your messages will fail to deliver to a contact who indicates that they don’t want to receive your texts. 

8. The Contact Has a Billing Issue or Hasn’t Paid Their Bill

Occasionally, a recipient may go over their plan or be in debt to a cell phone provider. 

In these circumstances, the provider or carrier may turn off that phone number’s ability to send and receive messages to encourage the user to pay what they owe. 

9. The Phone Settings Have “Receive SMS Messages” Turned Off

It is possible that the contact you’re sending messages to has turned off their phone’s ability to receive SMS. 

While SMS is common in the U.S., in other areas of the world, platforms like Whatsapp and Telegram are more widely used. 

If the SMS setting is deactivated, your messages won’t be delivered.

10. The Carrier Is Experiencing Technical Difficulties

Sometimes message deliverability is just out of your control. There may be times when the wireless carrier or their hardware is having technical difficulties, which can prevent messages from reaching your contact’s phone.

Avoid Undelivered Text Messages With the Right Phone Number

Many of the reasons your text messages aren’t sending can be attributed to the type of message you’re sending or the way you’re sending it.

Have a question about message deliverability? We love answering any and all questions about texting. Chat with our customer support team by clicking on the blue button at the bottom of your screen.