---
title: "What is SMS pumping?"
url: "https://lookvalid.com/glossary/sms-pumping.md"
canonical_url: "https://lookvalid.com/glossary/sms-pumping"
last_updated: "2026-10-18"
type: "conceptual"
summary: "SMS pumping is fraud in which attackers trigger large numbers of text messages, such as one-time passcodes, to phone numbers they profit from."
related: ["https://lookvalid.com/glossary/voip-number.md", "https://lookvalid.com/glossary/line-type.md", "https://lookvalid.com/glossary/toll-free-number.md", "https://lookvalid.com/products/phone.md", "https://lookvalid.com/products/phone-spam.md"]
---

# What is SMS pumping?

SMS pumping is fraud in which attackers trigger large numbers of text messages, such as one-time passcodes, to phone numbers they profit from.

The fraud works because some carriers share the fee for each delivered message with the number's owner. The attacker submits your sign-up or login form with numbers in those ranges, and you pay for every message sent.

Common defences are rate limits per number and per client, checking the number type and country before sending, and watching for bursts of requests to unusual ranges.

## Related

- [What is VoIP number?](https://lookvalid.com/glossary/voip-number.md)
- [What is Line type?](https://lookvalid.com/glossary/line-type.md)
- [What is Toll-free number?](https://lookvalid.com/glossary/toll-free-number.md)
- [Phone Numbering-Plan Validation API](https://lookvalid.com/products/phone.md)
- [Phone Spam Check API](https://lookvalid.com/products/phone-spam.md)