Businesses should always use A2P routes for compliance, speed, and guaranteed delivery.
A Tier-1 route connects directly to a mobile operator without intermediaries. This ensures the highest delivery rate, fastest speed, and better sender ID control. While slightly more expensive than gray routes, Tier-1 connections are 100% reliable and compliant with local telecom regulations.
A gray route uses unofficial or indirect channels to send messages at a lower cost. Although initially cheaper, gray routes are unstable and can lead to delivery failures, blocked sender IDs, or even blacklisting by operators. For professional and long-term use, gray routes are not recommended.