LoRa & Mesh Frequency Guide
LoRa transceivers do not sweep frequencies looking for packets; they listen on fixed center frequencies and exact channel bandwidths. If your transmitter and receiver disagree by even 50 kHz, packets vanish. This is the complete channel blueprint for Meshtastic, LoRaWAN (all US915 sub-bands and EU868), and point-to-point links.
01 · Meshtastic Default Frequency Slots
Meshtastic divides regional spectrum into numbered frequency slots. In the US, the center frequency follows an exact mathematical formula based on slot number:
| Region | Default Slot | Center Frequency | Bandwidth | Field Application & Notes |
|---|---|---|---|---|
| US915 (Americas) | Slot 20 | 906.875 MHz | 250 kHz | Standard US community mesh frequency. Sits comfortably between LoRaWAN Sub-band 2 uplinks and downlinks. |
| EU868 (Europe & UK) | Slot 0 | 869.525 MHz | 250 kHz | Targets the high-power ETSI sub-band, allowing 10% duty cycle and up to 500 mW ERP instead of the 1% cap. |
| AU915 (Australia & NZ) | Slot 20 | 916.875 MHz | 250 kHz | Shifted upward into 915–928 MHz to avoid interfering with Australian commercial cellular licenses below 915 MHz. |
| AS923 (Asia & Pacific) | Slot 1 | 923.000 MHz | 250 kHz | Used across Japan, Taiwan, Singapore, and parts of Southeast Asia adhering to the AS923 plan. |
LongFast preset uses 250 kHz bandwidth, while custom telemetry modes often drop to 125 kHz or 62.5 kHz. A node on 906.875 MHz with 125 kHz BW will never hear a packet sent on 906.875 MHz with 250 kHz BW.
02 · US915 LoRaWAN: Complete Sub-Band Roster (All 64 Channels)
The official US915 LoRaWAN specification defines 64 separate 125 kHz uplink channels (numbered 0 through 63) from 902.3 MHz to 914.9 MHz spaced 200 kHz apart, plus 8 500-kHz uplink channels (64–71) and 8 500-kHz downlink channels (0–7).
Because most DIY gateways (Heltec, Dragino, RAKwireless) contain only an 8-channel concentrator, the band is divided into eight separate sub-bands. Sub-band 2 is the universal North American standard:
| Sub-Band | 125 kHz Channels | Uplink Freq Span | 500 kHz Uplink | 500 kHz Downlink | Notes |
|---|---|---|---|---|---|
| Sub-band 1 | Ch 0 – 7 | 902.3 – 903.7 MHz | Ch 64 (903.0 MHz) | Ch 0 (923.3 MHz) | Lower edge of US915 band. |
| Sub-band 2 | Ch 8 – 15 | 903.9 – 905.3 MHz | Ch 65 (904.6 MHz) | Ch 1 (923.9 MHz) | De facto standard for The Things Network (TTN) and Helium in North America. |
| Sub-band 3 | Ch 16 – 23 | 905.5 – 906.9 MHz | Ch 66 (906.2 MHz) | Ch 2 (924.5 MHz) | Upper edge touches Meshtastic default frequency (906.875 MHz). |
| Sub-band 4 | Ch 24 – 31 | 907.1 – 908.5 MHz | Ch 67 (907.8 MHz) | Ch 3 (925.1 MHz) | Upper edge touches classic US Z-Wave channel (908.4 MHz). |
| Sub-band 5 | Ch 32 – 39 | 908.7 – 910.1 MHz | Ch 68 (909.4 MHz) | Ch 4 (925.7 MHz) | Mid-band allocation. |
| Sub-band 6 | Ch 40 – 47 | 910.3 – 911.7 MHz | Ch 69 (911.0 MHz) | Ch 5 (926.3 MHz) | Upper edge approaches Z-Wave Long Range (912.0 MHz). |
| Sub-band 7 | Ch 48 – 55 | 911.9 – 913.3 MHz | Ch 70 (912.6 MHz) | Ch 6 (926.9 MHz) | Overlaps Z-Wave Long Range 912 MHz channel. |
| Sub-band 8 | Ch 56 – 63 | 913.5 – 914.9 MHz | Ch 71 (914.2 MHz) | Ch 7 (927.5 MHz) | Upper edge of 125 kHz uplink allocation. |
Sub-Band 2 Channel Breakdown (The North American Default)
If you flash generic LoRaWAN firmware without locking it to Sub-band 2, your node will randomly rotate across all 64 channels — causing 87.5% of join requests to be sent on frequencies your gateway never hears. These are the exact 8 frequencies your gateway listens to:
| Channel Index | Center Frequency | Bandwidth | Role |
|---|---|---|---|
| Channel 8 | 903.9 MHz | 125 kHz | Standard 8-Channel Gateway Uplink |
| Channel 9 | 904.1 MHz | 125 kHz | Standard 8-Channel Gateway Uplink |
| Channel 10 | 904.3 MHz | 125 kHz | Standard 8-Channel Gateway Uplink |
| Channel 11 | 904.5 MHz | 125 kHz | Standard 8-Channel Gateway Uplink |
| Channel 12 | 904.7 MHz | 125 kHz | Standard 8-Channel Gateway Uplink |
| Channel 13 | 904.9 MHz | 125 kHz | Standard 8-Channel Gateway Uplink |
| Channel 14 | 905.1 MHz | 125 kHz | Standard 8-Channel Gateway Uplink |
| Channel 15 | 905.3 MHz | 125 kHz | Standard 8-Channel Gateway Uplink |
| Channel 65 | 904.6 MHz | 500 kHz | High-Throughput Wide Uplink |
03 · European EU868: Complete Channel Roster & Duty-Cycle Tiers
In Europe under ETSI regulation EN 300 220, all standard LoRaWAN networks share a standardized 8-channel plan. All nodes must support the first three mandatory channels out of the box:
| Channel | Frequency | Bandwidth | Data Rates | Duty Cycle | Role & Legal Limits |
|---|---|---|---|---|---|
| Ch 0 | 868.100 MHz | 125 kHz | DR0 – DR5 (SF12 – SF7) | 1% | Mandatory Join Channel (All nodes must support) |
| Ch 1 | 868.300 MHz | 125 kHz | DR0 – DR5 (SF12 – SF7) | 1% | Mandatory Join Channel (All nodes must support) |
| Ch 2 | 868.500 MHz | 125 kHz | DR0 – DR5 (SF12 – SF7) | 1% | Mandatory Join Channel (All nodes must support) |
| Ch 3 | 867.100 MHz | 125 kHz | DR0 – DR5 (SF12 – SF7) | 1% | Extended Uplink (Configured after network join) |
| Ch 4 | 867.300 MHz | 125 kHz | DR0 – DR5 (SF12 – SF7) | 1% | Extended Uplink (Configured after network join) |
| Ch 5 | 867.500 MHz | 125 kHz | DR0 – DR5 (SF12 – SF7) | 1% | Extended Uplink (Configured after network join) |
| Ch 6 | 867.700 MHz | 125 kHz | DR0 – DR5 (SF12 – SF7) | 1% | Extended Uplink (Configured after network join) |
| Ch 7 | 867.900 MHz | 125 kHz | DR0 – DR5 (SF12 – SF7) | 1% | Extended Uplink (Configured after network join) |
| RX2 / High Power | 869.525 MHz | 125 kHz | DR0 – DR3 (SF12 – SF9) | 10% | High-Power Downlink & Meshtastic EU868 Default (500 mW ERP) |
The 869.525 MHz High-Power Advantage
Notice the difference between the 868.0–868.6 MHz band (1% duty cycle, max 25 mW) and 869.525 MHz (10% duty cycle, up to 500 mW ERP). That single frequency slice allows 6 minutes of airtime per hour and 20× the transmit power. That is why Meshtastic EU868 targets 869.525 MHz as its primary default slot.