Definition
Custom field
A column you add to your prospect data, such as industry or last order, that snippets can pull into every email.
A custom field is any piece of information about a prospect beyond the standard name, email, company and job title. It could be the machines they run, the city of their plant, the trade fair where you met, or the name of the product line you want to mention. Custom fields usually arrive as extra columns in a CSV and are mapped to the prospect record on import.
They matter because personalisation that works is about the reader’s situation. A line that says “your Poznań plant” or “since you already run two extrusion lines” is what makes a cold email read as written for one person. Custom fields are how you get that detail into a sequence at scale without typing each message by hand. They are also where import problems hide: a missing value in a field your template needs produces an email with a hole in it.
In Seegnals custom fields are created from CSV columns during import with column mapping, and used in sequences as {{field_name}} snippets with fallbacks. You can rename a custom field and every sequence that uses it follows. Prospects missing a field a snippet needs are held in the To check queue before the first send.