LTE-M vs NB-IoT: when to pick each
TL;DR
LTE-M wins when the device moves or needs low latency (asset trackers, alarms, wearables). NB-IoT wins when the device is static and needs multi-year battery with deep indoor coverage (meters, parking, sensors). When in doubt, check real coverage at your deployment country before standard specs.
Comparison table
| Criterion | LTE-M | NB-IoT |
|---|---|---|
| Mobility / handover | Yes, real cell handover | No, session drops on cell change |
| Typical latency | 100-500 ms | 1-10 seconds |
| Throughput | Up to 1 Mbps | 10-60 kbps |
| Power (aggressive PSM) | 5-10 yrs on lithium AA | 10+ yrs on lithium AA |
| Voice support | Yes (VoLTE Cat-M1) | No |
| Deep indoor coverage | Good (+15 dB vs LTE) | Excellent (+20 dB) |
| SIM/plan cost | Similar to LTE | Typically lower |
When LTE-M is the right choice
Devices that move or need the server to reach them with reasonable latency. LTE-M is the only LPWA with real mobility.
- ·Asset tracking and fleets
- ·Medical and safety wearables
- ·Portable alarms
- ·Mobile POS
- ·Anything with voice
When NB-IoT is the right choice
Fixed devices sending little traffic, needing multi-year battery, and deep coverage in basements, manholes, or rural areas under-served by LTE.
- ·Water, gas, electricity meters
- ·Parking sensors
- ·Smart lighting
- ·Rural environmental sensors
- ·Smart mailboxes
Verdict
If the device moves or needs voice, LTE-M, no question. If it is static, lives indoors, and battery rules, NB-IoT. For mixed fleets, NB+M multimode modems with automatic selection are common.
FAQ
Can I use the same modem for LTE-M and NB-IoT?+
Yes, Cat-NB+M modems (Quectel BG95, Sequans Monarch) support both. The SIM and plan must also support both.
Which has better coverage in Spain?+
LTE-M is geographically broader; NB-IoT shines indoors. Check the carrier coverage map at your specific sites before manufacturing.
What happens when 2G shuts down?+
Natural migration: meters and static telemetry to NB-IoT, mobile devices to LTE-M. Cat-1 bis is another option when LPWA is not needed.
More comparisons
eSIM (eUICC) vs SIM tradicional
eSIM (eUICC) wins on flexibility and long-term cost, especially when the product ships across countries. Traditional SIM still wins on simplicity and upfront price when the carrier will not change and volumes are low.
LTE Cat-1 vs LTE-M
Cat-1 wins if you need more bandwidth (CCTV, POS, gateways) or your target coverage is international without LTE-M guarantee. LTE-M wins if battery or deep indoor coverage is the priority and you can live with its bandwidth limits.
APN privado vs VPN
Private APN controls where device traffic exits and which IPs they get. VPN encrypts the path between that exit point and your data center. The norm in serious IoT: both together.