# The path from send to handset.

Bird reaches 150+ countries over 240 direct-to-carrier connections. When a carrier path degrades, we reselect the route in real time, before the next message goes out. And every send returns a carrier delivery receipt, so you always know whether the handset got it.

## The layer your send rides on.

Routing is the layer beneath the Bird SMS API. You call one endpoint with a from, a to, and a text; underneath, we resolve the recipient's carrier, pick a connection, and hand the message off. When a path goes bad, the route changes and your code does not.

## What the routing layer decides for you.

Resolved per message, behind one API call.

## Why direct-to-carrier beats an aggregator chain.

A lot of SMS traffic passes through two or three resellers before it reaches an operator. Each hop adds a place for the message to stall, for the price to climb, and for the delivery receipt to get dropped or faked. A direct connection removes those middlemen: the message goes from Bird to the carrier, and the receipt comes back the same way. That is how about 40% of the world's commercial SMS already runs through this network, with 95% of messages delivered in under 2.5 seconds.

## Routing leans on number intelligence.

The MNP lookup that picks the right carrier is the same number intelligence you can call on its own with Lookup — line type, current operator, and portability before you send. Once a message is on the wire, wire up webhooks for the delivery receipt and read the error reference to handle each failure code, or check the deliverability guide for what the receipts tell you.

## Routing you never have to think about.

Coverage, carrier connectivity, failover, and delivery receipts are one capability of the Bird SMS API, on infrastructure we've run for a decade.