Blog de LabsMobile noticias y novedades

SMS gray routes: what are they and how to avoid them

In recent years of digitization and penetration of mobile devices, many companies have had to adapt to new forms of relationships between people and also to new ways of reaching customers outside the conventional.

Planning an SMS strategy involves an investment of money that companies have to face. Let's remember that the volume of SMS being sent is high and along with them the cost, but that will depend on the route chosen to send mass messages to mobiles. Nowadays you can find different routes, of different quality, and, of course, the lower the quality, the cheaper it will be (and so will be its effectiveness).

14 minutes of reading
Publication: 12.14.2023
Última modificación: 12.14.2023

What are connection routes in SMS?

When we talk about routes of connection in SMS, we refer to the path the message has to follow from a web platform to the receiver’s phone. As we mentioned above, there are many types of routes with different features based on functionality, reliability, and price

Direct routes are the most reliable and recommended, as they maximize performance at a higher price. These direct routes (or also called 0 hop) connect directly with the mobile operators in the destination country of the SMS messages. In other words, there are fewer intermediaries and they provide a higher reliability and delivery rate.

All other routes are considered indirect and depending on the intermediaries or redirections (1 hop, 2 hop or hops, etc.) are classified into routes of more or less quality and reliability.

This classification is very important if our service or SMS communication needs require a high rate of deliverability. It is always advisable to opt for a direct route to obtain a maximum delivery rate or reliability despite its higher cost.

Indirect routes include gray, wholesale or low quality routes that guarantee only partial delivery and may suffer blockages or incidents without the possibility of obtaining support or traceability.

Direct vs. grey routes

Direct routes are the ones that have some kind of agreement with a telephone company in a country. These are the most reliable ones because the entities that intervene are minimal. Besides, this reduces to a minimum the number of issues and has a short time of delivery These direct routes are subject to clauses and conditions imposed by operators so you won’t have any complications when it comes to legal matters. 

There are many advantages of these direct routes, including: 

  • Security in connection
  • Reliability
  • High availability of services
  • Alerts in case of issues or programmed maintenance
  • High delivery rate
  • Confirmation of delivery and error reports
  • Complaince with the law when it comes to data protection. 

However, direct routes may require some restrictions and conditions depending on the country or operator, such as:

-Pre-registration of the sender by providing official data and completing a registration prior to shipment.

-Pre-registration of the content based on templates with variables that must be submitted and approved in advance.

-Sending restrictions by time of day or holidays.

-Restrictions by content: political, official aid, tobacco, etc.

-Specific regulations by sector or content such as recovery.

Grey routes, on the other hand, are more economical but can pose problems not only in the delivery or non-delivery of messages but also in legal repercussions or complaints from the affected parties or recipients.

These do not have a direct agreement with the telephone operators, nor do they comply with the regulations or conditions of the operators. These routes can have serious reliability problems and even fail to comply with legislation and incur sanctions or penalties if they are used.

What type of grey routes exist? 

There are two main type of routes: 

  • Wholesale routes. These are the ones that take advantage of roaming agreements of different countries to send messages without cost, resending messages across different countries until they reach the destination. These routes are cheap but the delivery rate is very low. They can also suffer from down service without warning and frequently.
  • SIM routes. These simulate the sending of SMS massively as if they were messages between people but by using MultiSIM devices. These routes are forbidden and blocked by operators because they don’t comply with commercial clauses. They are easy to detect because the messages are identified with a local or international mobile number.

Due to the exponential increase in cases of fraud, phishing and other bad practices in the SMS channel, telephone operators have increased and improved the detection of gray routes and thus be able to monitor and control the traffic of SMS messages.

If these routes are detected, they immediately block the messages and could even result in sanctions or complaints against the company that used this medium as a means of SMS communication.

What are the disadvantatges of using the Grey Routes?

If we talk about the advantages of grey routes, we can say that they are cheaper. However, it’s important to remember that cheap things can end up being very expensive. And by expensive we mean it can bring about serious problems to your company that are not easy to solve.

This is when we should mention the disadvantages of taking these grey routes for sending SMS marketing.

  • Not complying with RGPD. Grey routes can obtain data of clients outside of the Europen Union, in countries where it’s not legal to transfer information. As you are responsible for this, you may receive a fine, which can be serious and amount between 40.000 and 300.000 euros €.
  • Not complying with the communications law in your target country, therefore committing involuntary crimes and being exposed to failure and sanctions. 
  • Your messages can be sent with the same receiver they used for other services with a low reputation or fraudulent.
  • Many SMS don’t reach their destination because information can be lost. 
  • The service can fail so the information is completely lost. Your clients may never receive your promotion, discount, alert, codes, etc.
  • Delay when sending SMS. Indirect routes (grey routes) are well known for their huge delays to send SMS. This is not good when you have to send important or urgent news to your clients in a quick manner. 
  • Reduced features. There are many features crucial when carrying out an SMS marketing campaign. For example, personalizing the sender of the message, scheduling the message in certain times, attaching down reports and many more that grey routes do not allow for.
  • Non-existing reports.We know that, when we start a marketing campaign, the most important thing to know whether it’s working or not is to have a report with open rates, number of clicks in URLs, where the client is and much more. Grey routes do not offer these features, unfortunately.

Almost no control over Grey Routes in SMS

The main disadvantage of choosing a grey route to carry out your SMS marketing campaing is that you won’t have control of anything that’s going on. You won’t know if the campaign is working, if the message is being delivered, if telephone companies can discover your company and tell the authorities, etc.

That is why it’s important to trust a well-known company or service, with experience and that complies with all the data protection laws in the country you want to target. At the end of the day, it’s the highest investment but you will earn double or even triple the money if you have a good strategy.

In LabsMobile, we only use direct routes, reliable and with great quality that offer local operators in every country. All of them comply with norms and legislation for sending B2C SMS messages. Try it today at a special trust, with trust and immediate delivery time.

Our team advises you

Interested in our services?

Our managers and technical team are at your disposal to answer all your questions about our SMS solutions and to advise you on the implementation of any action or campaign.

Contact us at