What’s the difference between tags and fields
Tags and custom fields are both used to store information about your subscribers, but we recommend using them in different situations.
Custom fields
You can use custom fields in forms so that subscribers can fill them in to provide information about themselves when signing up. Then, you can use these values to populate custom content in your campaigns for more personalisation.
Since custom fields can be text, numbers and dates, you can use them in advanced segmentation. For example, you can look for values that contain a specific phrase, numbers greater than a provided value, or dates before a specific day.
Tags
Tags are more straightforward – they’re text values that you assign to subscribers on your own by adding them manually or through an import. They can’t be used in campaigns for personalisation. In segmentation, you can use them to find people who have (or not) a specific tag assigned to them.
Which one should I use?
If you need a way to store some data that will be present in your email marketing campaigns and you wish to store it for a long time, then it’s best to use fields.
Tags are easy to create and use, so they’re a great choice if you only want to quickly assign some piece of information to a selected group of contacts for your internal segmentation purposes.