Documentation Index
Fetch the complete documentation index at: https://developers.telnyx.com/llms.txt
Use this file to discover all available pages before exploring further.
SIM Types
All Telnyx SIMs are eUICC-enabled. Three form factors:
| Type | Form Factor | Delivery | Use Case |
|---|
| SIM Card | Triple-cut plastic (2FF/3FF/4FF) | Shipped | Routers, gateways, traditional devices |
| eSIM | Software profile | Over-the-air download | Phones, tablets, laptops — no physical SIM needed |
Resource Model
Three core resources, all API-managed:
- SIM Card — the connectivity entity. Has an ICCID, status, data settings, optional voice flag. Covers both physical SIMs and eSIMs (eSIMs are purchased via a separate endpoint but become the same SIM Card resource with an activation code for OTA provisioning). Everything starts here.
- SIM Card Group — bulk management. Apply data limits, network preferences, and Private Wireless Gateway configs to all SIMs in a group at once.
- Mobile Phone Number — optional. Created when you enable voice or messaging on a SIM. Controls call forwarding, caller ID, messaging profile.
SIM Lifecycle
Order → Register → `enabled` → [Active Use] → `disabled` / `standby`
| Status | MRC | Data | Description |
|---|
| Registered | $2/mo | No | SIM exists in your account, not yet on network |
enabled | $2/mo | Yes | Active on network, consuming data |
disabled | $0.20/mo | No | Off network, reduced cost, retains config |
standby | $0.20/mo | No | Same as disabled, ready for quick re-enable |
Multi-IMSI
Every Telnyx SIM carries multiple IMSIs (Telnyx, Sparkle, BICs, T-Mobile, US Cellular). An on-SIM applet automatically selects the best IMSI per location — local network attachment instead of roaming, lower latency, better rates.
Default is automatic selection. You can override to manual per-SIM or per-group via API if you need to pin a specific IMSI for regulatory or testing purposes.
Pricing
Three cost components:
| Component | Cost |
|---|
| SIM purchase | 1/SIM,0.70/eSIM. $10 shipping outside US mainland. |
| Monthly | 2/activeSIM,0.20/disabled or standby |
| Data | Tiered by zone and volume. Full breakdown → |
