The best approach for country-by-country segmentation depends on whether you're working with email, SMS, or both. Here's how to handle each scenario:

For SMS Segmentation

Use phone number country code — this is the most reliable method for SMS subscribers:

1. Create a segment with the condition: Properties about someone > country code > equals > [country code]
2. Enter the specific country code you want to target (e.g., "US" for United States)

This approach works better than other location data because phone numbers inherently contain geographic information. How to segment SMS subscribers by country

For Email Segmentation

Use the standardized country property for cleaner, more reliable segmentation:

1. Create a segment with: Properties about someone > $country_transformed > equals > [country name]
2. Enter the standardized country name (e.g., "United States")
3. For multiple countries, combine conditions with OR operators

The $country_transformed property eliminates issues with country name variations (like "US" vs "USA" vs "United States"). How to standardize country names and utilize standardized properties

Best Practices

From our experience: Don't just segment by country alone. Layer in engagement and interest-based criteria for better performance:

• Country + engagement level (active vs. inactive subscribers)
• Country + purchase behavior (VIP customers vs. first-time buyers)
• Country + product interests for more relevant messaging

For flows: Use conditional splits with either phone number country code (SMS) or the $country_transformed property (email) to create location-specific paths. Basics: multinational SMS sending with Klaviyo