What is Cat M?
LTE Cat M (also known as LTE-M) is a low power wide area (LPWA) technology designed to support “Massive IoT,” enabling billions of connected devices to communicate over cellular networks. As of today, Cat M typically refers to Cat M1, while Cat M2 adoption is still a few years away.
LTE radio technology uses “categories” to define the capabilities of devices on an LTE network. For example, Cat 1 supports download speeds up to 10 Mbps, while Cat 4 goes up to 150 Mbps using carrier aggregation. Cat M1 devices operate over a narrow 1.4 MHz channel with download speeds around 589 Kbps and upload speeds up to 1.1 Mbps (3GPP Release 14). Older Cat M versions offer slightly lower throughput.
Cat M offers significant advantages for both mobile network operators (MNOs) and IoT solution providers:
- For MNOs, Cat M’s narrow bandwidth means each cell site can accommodate more devices, improving spectral efficiency and network economics.
- For IoT builders, Cat M enables lower-cost modules, longer battery life, and faster connection times, making it ideal for devices with constrained power budgets.
Power-Saving Features of Cat M
Cat M includes several power-saving enhancements that make it a strong fit for battery-powered IoT deployments:
Power Saving Mode (PSM)
PSM allows an IoT device to “sleep” for extended periods without being woken up by the network. Normally, devices transition between IDLE and ACTIVE modes, consuming power during network paging. With PSM, devices can negotiate sleep periods (from hours to days), and the network buffers a limited amount of data (e.g., last 100 bytes) for delivery once the device wakes up.
Extended Discontinuous Reception (eDRX)
eDRX lets devices sleep and wake up on a fixed cycle (the eDRX cycle), reducing how often they’re paged. Devices negotiate this cycle with the network to avoid unnecessary wake-ups. For example, eDRX can extend paging intervals from the default 1.28 seconds to up to 10.24 seconds, conserving battery even further.
PSM and eDRX are complementary, and most modern Cat M networks support both. Their combined use dramatically reduces power consumption for IoT devices in the field.
Current Constraints of Cat M Networks
Despite its benefits, Cat M comes with a few trade-offs:
- Lower Bandwidth: Typical real-world speeds are around 300 Kbps, making it unsuitable for high-throughput applications.
- Limited Global Coverage: Cat M is not available in all countries, and even where LTE exists, not all operators support Cat M yet.
- Risk of Preemption: In congested areas, Cat M devices may be temporarily disconnected to prioritize higher-tier LTE users.
Typical Cat M Use Cases
Cat M is ideal for devices that are low power, transmit small data packets, and do not need constant connectivity. Examples include:
- Asset tracking (e.g., waste bins, containers)
- Smart meters (e.g., water, electricity, air quality sensors)
- Smart agriculture and irrigation
- Industrial sensors in hard-to-reach or off-grid locations
Essentially, any device powered by a small, non-replaceable battery benefits from Cat M’s efficiency.
When LTE Cat 1 is Better than Cat M
If your IoT solution demands a persistent “always-on” connection, LTE Cat 1 or higher (Cat 3/4) may be a better fit. In these cases:
- Devices don’t leverage Cat M’s power-saving features.
- More bandwidth is needed for frequent or large data transfers.
- Broader LTE coverage is required, especially in countries where Cat M isn’t yet supported.
- You use communication protocols like PPP, which are less compatible with Cat M’s sleep modes.
KORE and LTE-M for IoT
KORE is a leading global IoT solutions provider offering deep expertise and coverage in LTE-M (Cat M) connectivity. With the acquisition of Twilio’s IoT business, KORE has further strengthened its ability to deliver scalable, reliable, and secure cellular connectivity across all LTE categories – including Cat M.
KORE’s global eSIM and multi-carrier Super SIM solutions are designed to automatically select the best available network for your device – whether you’re deploying battery-operated sensors in remote regions or mobile assets that require consistent global coverage.
KORE supports Cat M devices on a wide range of networks worldwide and offers advanced features like:
- eDRX and PSM enablement for extended battery life
- Unified device management through KORE One™ platform
- Regulatory compliance and certification services
- Global reach across 190+ countries
Whether you’re deploying a smart metering solution, an environmental sensor network, or mobile tracking for logistics, KORE gives you the flexibility and control to optimize connectivity for power, performance, and cost.
Ready to deploy with Cat M?
Contact KORE to explore your IoT connectivity options or get a test SIM to evaluate coverage and performance for your devices.
Published April 29, 2025.