What Is a Mailing List? A Plain-English Guide

A mailing list is a collection of email addresses that receive the same messages. When you send one email to the list, everyone on it gets a copy. That's it. The details are in who can send, how people join and leave, and how you keep the list in good shape.

The two main kinds of mailing list

Announcement lists (newsletters)

One sender, many readers. A shop's weekly offers, a realtor's market update, a club's monthly newsletter. Readers receive messages but don't reply to everyone. This is what most businesses mean by "my mailing list" or "my email list".

Discussion lists (listservs)

Many senders, many readers. Any member can write to the list's address and every other member receives it, so the list works like a group conversation by email. These are common in universities, professional groups and open-source projects. People often call them "listservs" after LISTSERV, one of the first programs that ran them.

How a mailing list works

Behind the scenes, mailing lists are run by software. For newsletters that's usually an email marketing service like Mailchimp, Constant Contact or MailerLite. For discussion lists it might be Google Groups or a listserv program. The software does four jobs:

• Stores the subscribers, often with names and other details.
• Handles joining, usually through a sign-up form and sometimes a confirmation email.
• Handles leaving, with an unsubscribe link in every message.
• Sends the mail to everyone, and tracks bounces so dead addresses can be removed.

How to start a mailing list the right way

1. Choose a service. Don't send newsletters from a personal Gmail or Outlook account with everyone in BCC. You'll hit sending limits, you won't have unsubscribe links, and your messages are more likely to land in spam.
2. Only add people who asked. Use a sign-up form on your website, a checkbox at checkout, or a paper sign-up sheet at an event. Buying lists or scraping addresses is the fastest way to ruin your sending reputation.
3. Consider confirmed opt-in. A "please confirm" email stops typos and fake sign-ups getting onto your list. Our guide to stopping fake sign-ups explains how.
4. Follow the rules. In the US, the CAN-SPAM Act requires commercial emails to include a working unsubscribe option and your physical postal address, and you must honor unsubscribe requests promptly. Other countries have their own rules.
5. Send something worth reading, on a schedule people expect.

Moving an existing list into a new service

If you already have contacts in a spreadsheet or CRM, clean the file before you import it: remove duplicates, fix typos and make sure every row has one valid address. Our guides cover preparing a CSV for import and merging several lists, and the free List Fixer does most of it in one step.

Keeping a mailing list healthy

Lists decay. People change jobs, abandon old inboxes and mistype their address on forms. A list that is never cleaned slowly fills with addresses that bounce, and a high bounce rate tells mailbox providers you're a careless sender. A few habits keep a list healthy:

• Remove hard bounces after every send.
• Keep a suppression list of everyone who unsubscribed or bounced.
• Re-check older contacts before a big send. See how often to clean a list.