Channel & craft
Custom attribute
Also known as: custom field · user property
A user-level data field, beyond the built-in properties like email and first_name, that stores brand-specific information (subscription tier, last-purchase date, NPS score) for use in segmentation and personalisation.
A custom attribute in Braze (or equivalent field in other platforms) is a user-level data slot beyond the built-in properties. Every platform ships with defaults: email, phone, first_name, last_name, created_at. Operators add custom attributes to capture brand-specific state: subscription_tier, last_purchase_date, nps_score, product_interests, churn_risk_band. Custom attributes are the backbone of segmentation and personalisation: segments filter on them, Liquid renders them, triggers fire when they change. Design principles: name them consistently (snake_case, typed prefixes: dt_ for dates, is_ for booleans, n_ for counts), avoid redundant attributes (if derived from events, keep the event and compute when needed), and audit for unused attributes quarterly. Every platform has instances with 200+ attributes where 150 haven't been read in years.
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