What’s the difference between full migration and split delivery?

Full migration and split delivery are different strategies with different goals.

Full migration:

• Move all sending from old ESP to new ESP
• End state: one ESP handles everything
• Simpler long-term management
• Temporary parallel running during transition

Split delivery:

• Permanently route different email types through different providers
• Example: Transactional through SendGrid, marketing through Klaviyo
• Each ESP optimized for its use case
• Ongoing management of multiple platforms

Why choose split delivery:

Specialization: Different ESPs excel at different things (transactional speed vs marketing features)

Reputation isolation: Keep transactional separate from marketing to protect critical emails

Redundancy: Multiple providers reduce single-point-of-failure risk

Best-of-breed: Use best tool for each job rather than compromise on one platform

Why choose full migration:

• Simplicity: One vendor, one dashboard, one integration
• Data centralization: Complete subscriber view in one system
• Cost efficiency: Often better pricing with consolidated volume
• Reduced complexity: Fewer systems to manage and troubleshoot

Some organizations start with full migration planning and evolve to split delivery as needs become clearer.