Yes, a Band 4 signal booster can work with Band 66 — but with some important caveats:
✅ Why It Can Work:
- Band 66 is an extension of Band 4, using the same core frequencies for uplink and downlink (1710–1755 MHz uplink, 2110–2155 MHz downlink).
- Most of the main portion of Band 66 overlaps with Band 4, so many boosters designed for Band 4 will still provide a benefit.
⚠️ Why It Might Not Fully Work:
- Band 66 includes extended downlink (2155–2200 MHz) and uplink (1755–1780 MHz) that Band 4-only boosters may not amplify.
- If your phone or carrier uses the extra bandwidth of Band 66 for higher data speeds or better signal, you may not get the full benefit with a Band 4-only booster.
💡 Recommendation:
If you want future-proof performance, especially with newer phones and LTE-A/5G deployments:
- Choose a signal booster that explicitly lists Band 66 support.
- Look for multi-band boosters certified by the FCC or ISED (Canada) that cover Bands 2, 4, 5, 12, 13, 66, and 71.
