Which carriers do our SMS get delivered to?

To guarantee a reliable service, we made a choice right from the start of the project: use real GSM lines with French carriers, instead of relying on a wholesale SMS API.

Why?

Wholesale SMS APIs (SMTP/HTTP gateways) are convenient but come with several limitations:

• Sender numbers are shared: another customer can get the gateway blacklisted.
• Carriers' anti-spam filters are stricter for these flows.
• Costs climb quickly and are incompatible with a free service.

Our choice: direct GSM

We run our own 3G/4G GSM modems with Orange, SFR and Bouygues SIM cards. Every message literally goes out as if from an ordinary phone:

• Excellent deliverability to all three networks.
• No middleman between us and the carrier.
• Smart routing: if a SIM reaches its quota, the message switches to another one.

Which carriers are supported?

All French carriers are supported on the receiving end:

• Orange / Sosh
• SFR / RED
• Bouygues / B&You
• Free Mobile
• And every MVNO (Lebara, La Poste Mobile, Prixtel, Coriolis…)

The number simply has to start with 06 or 07 and contain 10 digits.