What are SIM farms and why you want to avoid them

Like Google, you may think a SIM farm is an old video game (go ahead, Google it!). But when it comes to SMS messaging, a SIM farm is nothing like a fun and harmless video game. SIM in this context is referring to a subscriber identity module, or SIM card in a mobile device. Every mobile on a GSM network uses one. It contains information about the owner and mobile including number, contact lists, network authorisation.

So imagine a large group of these SIM cards, connected to computer servers rather than in individual mobile devices. Then imagine someone selling SMS services using that set of SIMS and servers to connect to mobile networks. Then you have a SIM farm.

But that doesn’t sound so bad does it?  If you’re the one trying to send SMS messages using the farm, it is bad. Here are three reasons why:

The setup is technically inferior – Using a SIM farm as your primary method of sending SMS messages is the same as hiring a bunch of people to send your texts using their mobiles. SIM cards can only handle a small amount of messages at a time, so if you’re sending bulk messages they won’t all go out in a timely fashion. And because the SIM has just a single connection to the mobile network, if the there’s any kind of error in that connection, your message will get lost and never delivered. Without redundancy and an infrastructure built to handle large amounts of messages, SIM farms can’t compete with legitimate SMS providers performance.

They violate network fair usage agreements – In the fine print that no one reads, most networks include wording that prohibit bulk SMS messages being sent from one SIM card. This is because thousands, or even millions, of people share the same network resources. If one person tried to send 100,000 messages at once using a SIM card, it would overload the network and other people’s messages wouldn’t get through. That’s why it’s often referred to as “fair usage” in contracts. It tries to ensure everyone shares the network resources evenly. Good SMS providers handle large message volumes in a variety of ways including throttling message volume and using approved SMS gateways that feed directly to the mobile networks without using the resources allocated to SIMs.

You can be guilty by association – SIM farm is a derogatory term. This is because they are usually connected to organisations that send SMS spam. Mobile networks have taken measures to find and block SIM cards being used by SIM farms. The Information Commissioner’s Office (ICO) conducts raids on SIM farms to shut them down due to the spam complaints they receive. If you’re a legitimate business using a SIM farm that gets shut down by the network or the ICO, you may get caught up in the investigation.

So why do businesses use SIM farms? Mostly because they are cheap. They offer unbelievably cheap per message pricing. But as the saying goes, if it seems too good to be true, then it probably is. There are even more reasons you don’t want to use a SIM farm such as the inability to specify a label number (like a VMN or shortcode). But the three I mentioned above are by far the most important.

But often the businesses that use them know they can send spam through them easily. Until they get caught that is. If you suspect your provider might be a SIM farm, contact them and see if they’ll answer your questions about their SMS gateway. Their response might be all you need to know if they are or they aren’t. Good SMS providers will be willing to explain their services to you in detail. If you’re still in doubt, shop around. Look at more than just prices. Compare services and features to what you have now. Chances are you’ll be able to tell the good from the bad.