I have multiple lists – how should I organise my contacts?
We're updating list management features in our platform, and some things mentioned in this article may not apply to new accounts. This guide is meant for accounts created before June 9th 2025.
When deciding on the best way to manage your contacts on EmailOctopus, it's important to keep in mind that lists are treated completely separately. If an email address is present on multiple lists, each time it's added counts as one contact in your total list size, potentially increasing your monthly subscription costs. This also means that in case you re-send an email across multiple lists, the duplicated contacts would receive the email multiple times. Finally, if a recipient that exists within multiple lists unsubscribes from one list, they'll remain subscribed on the other lists.
If you have a larger, clearly segmented audience, you might think about creating multiple lists for them. There are cases where this is an optimal solution – for example if you send emails for completely different brands, companies, niches, etc., and there is no overlap between people on your lists.
In other cases, where there is a possible overlap of contacts, like when you have lists of people who bought a specific product from you, it's better to keep all your contacts on one main list and divide your audience into smaller subgroups through segmentation. That way, you can completely avoid the risks mentioned above – duplicating your contacts, sending the same content multiple times to the same subscribers, and re-adding people who already unsubscribed.
One more advantage of using one list and segmenting it is that you can easily send an email to several selected groups of your list at once. If you keep your contacts on multiple lists, you'd have to duplicate your campaign and resend it to each list separately.
Example of single list management
By default, lists don't have any custom fields and tags, but you can create them based on your specific needs. You can learn how to do that in the articles: Adding new fields and Using tags.
Let's say that you're an author who has written three books. They were published in English and Spanish. You already have a list of people who bought your books, and you know which language your readers prefer. You also have an option to generate unique discount codes for your other books.
If you were to separate readers into dedicated lists, you would need six of them, one for each book and a preferred language combination. Instead, you can add them all to one list and assign a tag corresponding to each book they bought. That way, you can have people who will end up with a 'First Book' tag, others with 'Second Book' and 'Third Book', and some might even have all of them. Each person would count only as one contact on your list. On top of that, you can import the information about their preferred language to EmailOctopus as a custom field. You can do the same for unique discount codes.
With such a list, you can easily create highly targeted campaigns. For example – you can create a campaign in English for your biggest fans who bought all your books and send it to people with 'English' value in their language field and all three tags.
Or, you can create a campaign asking your Spanish readers what they thought of your first book and let them know what else you've written. You can do that by sending it to people with the language field 'Spanish' and tag 'First Book' – but without tags 'Second Book' and 'Third Book'. Then, in the content of this email, you can include a merge tag to insert the discount code for your other books (more on that here: What is a merge tag and how to use it?).
If you'd like to learn more about sending campaigns to segments, we recommend this article: How to send a campaign to a segment.
There are advantages to that approach in automation, too. For example, you can create personalised automated 'Thank you' emails for each of the audiences when people buy one of your books with automations like this one:
These are just some simple examples – you can create more detailed segments of your audience by using multiple filters. You can review all the available segmentation options in this article: Using segmentation.
If you're not sure if you should use custom fields or tags for a particular piece of information, we explain their use cases here: What's the difference between tags and fields.
Updating your contacts on a single list
There might be situations when you get new information about your audience, and you'd like to update your EmailOctopus list to reflect that.
We'll stay with the author example – let's say you created a quiz for your readers, asking who is their favourite character. If it wasn't anonymous, you can update your list in EmailOctopus with this information to further expand your segmentation possibilities – for example, you can use this information to send short stories focusing on the favourite characters they chose in the quiz.
You can update existing contacts with new information automatically through an API integration or manually via import. If you use the latter, simply choose the option to update your existing contacts when you prepare your import.
I would like to use a single list, but I have already added my contacts to multiple lists
If you already have multiple lists, it's still possible to merge them. You have to export them out of the source list and then import them to the target list. We explain how to do that in detail in this article: How to merge multiple lists into one.