# Do-not-contact list explained | Propel

Source: https://runpropel.com/glossary/do-not-contact-list

Glossary

# What is a do-not-contact list?

A do-not-contact list, also called a suppression list, holds the people and addresses you must never write to again: those who unsubscribed, asked you to stop, or whose address bounced. Every send is checked against it first.

## Why keep one?

Laws such as CAN-SPAM and GDPR expect you to honour a request to stop, and mail providers punish senders who ignore it. A list kept in one place means a person who said no once is never surprised by a second email from another campaign.

## What belongs on it?

- Anyone who unsubscribed or replied asking to stop.
- Addresses that bounced or are known to be invalid.
- Anyone you mark yourself.

## How does Propel use it?

Every email and LinkedIn message passes one check before it goes: is this person or address on the list, or has their sequence stopped because they replied? The check runs when a campaign is set up and again at the moment of sending. An unsubscribe is kept even after the contact is deleted, so the person can't be added back by mistake. See [Get customers](https://runpropel.com/get-customers).

Where Propel does this

[Get customers →](https://runpropel.com/get-customers)

Related terms

- [One-click unsubscribe](https://runpropel.com/glossary/one-click-unsubscribe)
- [Bounce rate](https://runpropel.com/glossary/bounce-rate)
- [Email sequence](https://runpropel.com/glossary/email-sequence)
- [All terms](https://runpropel.com/glossary)