Frequencies & Regions
General Guides
Where these radios live
MeshCore and Meshtastic operate in license-free bands: ISM in North America, SRD in Europe. No exam, no callsign. In exchange, devices must tolerate interference from everything else in the band (baby monitors, meter readers, garage doors) and must obey regional power and duty-cycle limits. The firmware's region setting is what selects the band plan and those limits, which is why it must be set correctly before transmitting.
The major regions
| Region setting | Band | Key limits |
|---|---|---|
| US / Canada (US) | 902-928 MHz | FCC Part 15.247: up to +30 dBm (1 W) conducted, +36 dBm EIRP with an antenna up to 6 dBi. No duty-cycle limit. |
| Europe (EU_868) | 863-870 MHz | ETSI EN 300 220. Most sub-bands: +14 dBm (25 mW) ERP and around 1% duty cycle. The 869.40-869.65 MHz sub-band allows +27 dBm (500 mW) ERP at 10% duty cycle, which is why default channels sit there. |
| Europe (EU_433) | 433.05-434.79 MHz | +10 dBm (10 mW) ERP. 10% duty cycle across most of the band. The 434.04-434.79 MHz segment permits a higher duty cycle if occupied bandwidth stays within 25 kHz, which typical LoRa settings satisfy. |
| Australia / NZ (ANZ) | 915-928 MHz | 1 W EIRP for digital-modulation and frequency-hopping devices (this covers LoRa). Frequency hopping requires a minimum of 20 hopping frequencies. Plain transmitters are capped at 3 mW EIRP. New Zealand aligns under the joint AS/NZS 4268 standard. |
| India (IN) | 865-867 MHz | Up to 1 W (30 dBm) ERP, license-exempt under the WPC delicensed framework. The short-range-device band was extended to 865-868 MHz under the 2021 rules. No explicit duty-cycle limit for point-to-point LoRa, though 1% is common practice. |
| Japan (JP) | 920 MHz band | Governed by ARIB STD-T108. Up to 250 mW for the relevant station class, roughly 920.5-923.5 MHz, with mandatory listen-before-talk (carrier sense). Requires Giteki-certified equipment. |
Radio regulations change, and the limits above are simplified summaries that cannot capture every station class, sub-band, or national condition. Always confirm the current rules with your national regulator before transmitting. Limits last verified July 2026.
In practice the hardware rarely reaches the legal ceiling anyway: the SX1262 radio in most boards tops out at +22 dBm conducted, well under the US limit. In the EU the legal limits are lower than the hardware maximum, and the firmware region setting is what keeps you compliant.
Duty cycle, the non-obvious one
US operators rarely think about airtime legality because Part 15.247 does not impose a duty cycle. European SRD rules do: a node restricted to 1% duty cycle gets 36 seconds of transmit time per hour. Slow spreading factors burn multiple seconds of airtime per packet, so a chatty node on a slow preset can hit the ceiling. This is a real constraint in EU mesh design, not paperwork trivia.
Why the wrong region setting is doubly wrong
Transmitting on another region's band plan is illegal where you are, and it is also pointless: nobody else's radios are listening on those frequencies with those parameters. Set the region before the first transmit. Both firmwares refuse to transmit until a region is configured, but they cannot know if you picked the wrong one on purpose.
The ham-band overlap
In the US, 902-928 MHz is also the amateur 33 cm band. Licensed hams can run these radios under Part 97 rules instead of Part 15, which allows more power, with one important catch: Part 97 prohibits encrypted traffic, and these firmwares encrypt by default. That is why community meshes stay under Part 15 rules even when the operators hold ham licenses. If you go the ham route, you must disable encryption and identify per the rules.
Hardware follows the band
Boards are sold in band-specific variants. A 433 MHz board cannot be configured into a 915 MHz node; the radio and its matching network are physically built for one range. Buy the variant for your region, then set the region in firmware to match.