Custom Fields

Create and manage custom fields to store additional contact information for personalization

Custom fields allow you to store additional information about your contacts beyond their email address. Use these fields to personalize campaigns and create targeted segments.

What are Custom Fields? Custom fields are variables that store specific information about your contacts, such as:

Personal details (first name, last name, birthday)
Geographic information (city, country, timezone)
Preferences (product interests, communication frequency)
Custom data specific to your business

Default Fields

Every contact in Mailtrap has these default fields:

Primary identifier for contacts

Automatically created
Cannot be deleted or modified
Must be unique across your account
Used for sending campaigns

Tracks consent and engagement

Subscribed
Unsubscribed
Pending (awaiting confirmation)

Creating Custom Fields

Navigate to Fields

Go to Contacts → Fields in your Mailtrap dashboard.

Click Create Field

Select the Create Field button to open the field creation form

Configure Field Properties

Fill in the field details:

Field Name: Display name (e.g., "First Name")
Type: Select the appropriate data type
Merge Tag: Variable for personalization (e.g., first_name)

Merge Tag Format: Use underscores for multi-word merge tags (e.g., last_name, date_of_birth)

Save Your Field

Click Create to add the field to your account.

Field types

Choose the appropriate field type based on your data:

For short text values

Names, titles, company names
Short descriptions
Single-line inputs
Maximum 255 characters

Example: first_name, company, job_title

For numeric values

Age, scores, counts
Integers and decimals
Mathematical operations in segments

Example: age, purchase_count, loyalty_points

For date and time values

Birthdays, anniversaries
Registration dates
Last activity timestamps
Format: YYYY-MM-DD

Example: birthday, registration_date, last_purchase

For yes/no values

Preferences and flags
Subscription statuses
Feature toggles
Values: true/false

Example: is_vip, newsletter_subscriber, has_purchased

For predefined options

Categories, segments
Multiple choice values
Dropdown selections

Example: product_interest, customer_tier, preferred_language

Using Fields in Campaigns

Personalization with Merge Tags

Use merge tags to personalize your email content:

Example Email Template


</div>

### Dynamic Content

Create conditional content based on field values:

<div data-gb-custom-block data-tag="code" data-title='Conditional Content Example'>
```liquid

<div data-gb-custom-block data-tag="if" data-expression='preferred_language == "Spanish"'>

  Hola {{first_name}},

<div data-gb-custom-block data-tag="elsif" data-0='French' data-1='French' data-2='French'></div>

  Bonjour {{first_name}},

<div data-gb-custom-block data-tag="else"></div>

  Hello {{first_name}},

</div>

Best practices

Field fanagement tips:

Plan before creating: Map out all fields you need before importing contacts
Use descriptive names: Make field names clear and intuitive
Consistent naming: Use a naming convention for merge tags
Data validation: Choose appropriate field types to ensure data quality
Document usage: Keep notes on what each field represents

Technical limitations

Field name length: Up to 50 characters
Merge tag length: Up to 50 characters
Text field value: Up to 255 characters
Cannot delete fields with existing data
Each account can have up to 40 Fields.

PreviousOverview

NextImport Contacts

Last updated 2 months ago

Was this helpful?