What Is SMS Pumping Fraud?

SMS pumping fraud is one of the fastest-growing and most expensive forms of telecom fraud, and most businesses do not realize they are exposed to it until the bill arrives. Also known as artificially inflated traffic (AIT), SMS toll fraud, or international revenue share fraud (IRSF), it lets fraudsters quietly turn your own security features against you, running up enormous SMS costs with no legitimate users behind any of it.

This guide explains what SMS pumping fraud is, how the attack works, how to spot it early, and how to prevent it before it drains your budget.

What is SMS pumping fraud?

SMS pumping fraud is an attack where fraudsters artificially inflate the volume of SMS messages a business sends, so they can profit from the messaging fees. It targets any flow that sends a text automatically, such as one-time passwords (OTPs), account verification, and login codes.

The scheme works because the fraudsters control, or are partnered with, the numbers receiving those messages. By collaborating with complicit telecom operators, often in regions with light regulation, they earn a share of the revenue every time one of your verification texts is delivered. The more messages they can force your system to send, the more they make, and you pay for all of it.

You will see SMS pumping referred to by several names, including AIT, SMS toll fraud, and IRSF. They all describe the same basic abuse: turning legitimate SMS infrastructure into a revenue stream for fraud.

How SMS pumping works

The attack tends to follow a predictable pattern:

1.     Find a target. Fraudsters look for sign-up, login, or password-reset flows that send SMS codes without strong limits or validation.

2.     Generate traffic. Using bots, scripts, or low-cost click farms, they submit large numbers of requests for OTPs and verification codes.

3.     Point the messages at controlled numbers. The phone numbers receiving the codes are ones the fraudsters control or have arranged with a complicit carrier.

4.     Collect the revenue share. The carrier shares a cut of the messaging fees with the fraudsters, while your business absorbs the full cost.

Because the numbers are real and the requests look like ordinary sign-ups, the abuse can run for a long time before anyone notices.

Why SMS pumping is so costly

The financial damage adds up fast. Industry estimates put annual losses from SMS pumping and related fraud at more than $6.7 billion, and high-profile cases have seen large platforms report tens of millions of dollars in losses in a single year from fake verification traffic alone.

The cost is not only the inflated bill. A flood of fake requests strains your infrastructure, degrades service for real users, and skews the metrics your team relies on, since sign-up and verification numbers balloon with traffic that never converts.

There is also a structural reason the problem persists. Messaging providers earn money on the volume of messages sent, so they have limited incentive to aggressively block the very traffic they profit from. In practice, that leaves the responsibility for stopping SMS pumping with the business sending the messages.

Signs your business is being targeted

A few patterns are strong warning signs of an SMS pumping attack:

•       A sudden spike in OTP or verification requests with no matching growth in real sign-ups or sales.

•       A surge of traffic to phone numbers in countries or number ranges you do not normally serve.

•       A low completion rate, where many codes are requested but few are ever entered.

•       Repeated requests clustered around specific carriers, regions, or times of day.

Watching the ratio of messages sent to verifications actually completed is one of the quickest ways to catch an attack early.

Who is at risk?

Any business that sends automated text messages is a potential target. That includes any app or website using SMS for OTPs, two-factor authentication, account registration, or password resets. Companies operating internationally are especially exposed, because the global routing of SMS makes it easier for fraudsters to hide behind legitimate-looking cross-border traffic.

How to prevent SMS pumping

Stopping SMS pumping comes down to one principle: screen traffic before a message is ever sent, so fraudulent requests never trigger a paid SMS. A layered approach works best:

•       Rate limiting and velocity controls. Cap how many codes can be requested per number, per device, and per time window to break the rapid-fire pattern these attacks rely on.

•       Phone validation. Verify each number in real time and check its line type and carrier, since VoIP and other high-risk line types are frequently used in pumping. Real-time phone validation lets you flag suspect numbers before you send.

•       Phone risk scoring. Go beyond format checks with phone fraud scoring that draws on real-world usage patterns to flag numbers tied to abuse.

•       Bot detection. Stop the automated scripts and click farms that generate the requests in the first place, before they ever reach your SMS flow.

•       IP and proxy checks. Fraudsters mask their traffic, so proxy and VPN detection helps separate real users from anonymized abuse.

•       Device intelligence. Catch a single device firing off many requests, even when it rotates IP addresses or numbers.

•       Geolocation checks. Confirm that a user's IP location and phone country code line up, and scrutinize requests from high-risk regions.

•       Monitoring and alerts. Set alerts for sudden spikes so you can respond in minutes, not after the monthly invoice.

How IPQS helps stop SMS pumping

IPQS brings these defenses together so you can block risky traffic before a single message goes out. A dedicated SMS pumping detection capability flags phone numbers associated with pumping attacks, while device fingerprinting catches the automated tools and farms behind them, even across IP and number changes. For a deeper look at how IPQS blocks this threat across phone, device, IP, and behavior, see how IPQS stops SMS pumping.

SMS pumping vs. smishing

It is easy to confuse SMS pumping with smishing, but they are different threats. SMS pumping abuses your outbound messages to generate fees, with no interest in your users at all. Smishing, or SMS phishing, targets your users directly with deceptive texts designed to steal credentials or money. Both involve SMS, but one inflates your costs while the other attacks your customers.

Frequently asked questions

What is AIT?

AIT stands for artificially inflated traffic, another name for SMS pumping. It describes the same abuse: inflating SMS volume so fraudsters can profit from the messaging fees.

Is SMS pumping the same as toll fraud or IRSF?

They are closely related and the terms are often used interchangeably. SMS toll fraud and international revenue share fraud (IRSF) both describe schemes where fraudsters profit from artificially generated traffic, with SMS pumping focused specifically on inflated text-message volume.

How much does SMS pumping cost businesses?

Industry estimates put annual losses above $6.7 billion, and individual companies can face inflated SMS bills running into the millions per month if an attack goes unchecked.

How do I detect SMS pumping?

Watch for spikes in OTP requests, traffic to unusual countries or number ranges, and a low ratio of completed verifications to messages sent. Real-time phone validation, bot detection, and device intelligence let you flag this traffic before a message is sent rather than after the bill arrives.

Whose responsibility is it to stop SMS pumping?

In practice, the business sending the messages. Because messaging providers profit from volume, the most reliable protection comes from screening your own traffic at the point where codes are requested.

Protect your SMS flows with IPQS

The most effective way to stop SMS pumping is to catch fraudulent traffic before it triggers a paid message. Start a free trial with 1,000 free lookups per month, or schedule a demo to see how IPQS scores phone, device, and IP risk across your entire user journey.