List churn — the drops in your list size as people change email addresses without telling you or unsubscribe from your list — is inevitable. Many nonprofits lose 20-30% of their lists each year to this natural turn-over. How can you combat the churn and keep your list growing? Here are a dozen tactics you can use to keep your email list growing.

1. Send a regular e-newsletter to your list. Even if it is simply a short update that you send once a month, get in the habit of regularly sending mail to your list. An active list is much more likely to grow.

2. Include a simple sign-up box on your website, ideally on every page, but on your homepage at a minimum.

3. Make changing an address very easy. Ideally, subscribers to your newsletter can update their own email addresses with just a few clicks. The harder you make it, the less likely they are to do it and the more likely they are to drop off your list permanently.

4. Encourage readers to forward your e-newsletter to friends and be sure to include a link to your sign-up form in each edition so those friends can sign up directly.

5. When people register for your events, tell them they will receive your e-newsletter too.

6. Bring a paper sign-up sheet to all of your face-to-face events and include one at your reception desk if you get a lot of in-office foot traffic. Get in the habit of regularly entering those hand-collected addresses into your system.

7. Let supporters decide what they get. Segment your lists so that supporters can tailor the amount and type of information that you email to them. If people have control over what you’ll send, they are more likely to give you their email address.

8. Offer a special download. If lots of people come to you asking the same kinds of questions, create a guide or white paper with the answers. Explain that when they register for the free download, they’ll also be added to your e-newsletter list.

9. Sponsor a contest or drawing. Encourage people to sign-up by providing their email addresses.

10. Collect business cards at presentations. If you make lots of presentations, tell your audience that you will add them to your e-newsletter list if they leave their card with you.

11. Ask for email addresses on all of your forms. Let supporters sign up for your email newsletter on your membership forms, volunteer forms, event registration forms, and donation forms — anywhere you require a street address, ask for an email address too.

12. The most important tip of all: Offer great content! If people really like your newsletter, they won’t unsubscribe and they’ll make an effort to stay on your list when their email addresses change.

No matter which tactics you use to build your list, you should always make it clear that unsubscribing will be painless and that you will not sell their address to anyone else. That’s the best way to establish the trust you’ll need to succeed with your email marketing campaigns.

See our weekly webinar series and on-demand e-courses for more help with building your email list.