Below is the official reference list of supported regional carriers, network generations (2G/3G/4G), and frequency bands.
AT&T:
4G LTE: Band 2, Band 4, Band 5, Band 14, Band 17, Band 29, Band 30, Band 66
WCDMA (3G): Band 2, Band 5
T-Mobile:
4G LTE: Band 2, Band 4, Band 12, Band 66, Band 71
WCDMA (3G): Band 2, Band 4
GSM (2G): PCS1900
Verizon (Includes Alltel / Rural):
4G LTE: Band 2, Band 4, Band 13
CDMA2000 (3G): BC0, BC1
Bell Mobility:
4G LTE: Band 2, Band 4, Band 7, Band 17, Band 29, Band 42
WCDMA (3G): Band 2, Band 5
CDMA2000 (2G/3G): BC0, BC1
Rogers Wireless:
4G LTE: Band 4, Band 7, Band 12, Band 17
WCDMA (3G): Band 2, Band 5
GSM (2G): GSM850, PCS1900
Telus:
4G LTE: Band 4, Band 7, Band 29
WCDMA (3G): Band 2, Band 5
SaskTel:
4G LTE: Band 2, Band 5, Band 7, Band 13
UMTS (3G): Band 2, Band 5
Videotron:
4G LTE: Band 4, Band 17
WCDMA (3G): Band 4
AT&T Mexico (Nextel-Iusacell):
4G LTE: Band 2 (1900 MHz), Band 4 (1700 MHz), Band 7 (2600 MHz), Band 28 (700 MHz)
3G UMTS: 850 MHz, 1900 MHz
2G GSM: 850 MHz, 1900 MHz
Movistar (Telefónica):
4G LTE: Band 2 (1900 MHz), Band 4 (1700 MHz), Band 7 (2600 MHz), Band 28 (700 MHz)
3G UMTS: 850 MHz, 1900 MHz
2G GSM: 850 MHz, 1900 MHz
Telcel:
4G LTE: Band 2 (1900 MHz), Band 4 (1700 MHz), Band 7 (2600 MHz), Band 28 (700 MHz)
3G UMTS: 850 MHz, 1900 MHz
2G GSM: 850 MHz, 1900 MHz
Hutchison 3 UK (Three):
4G LTE: Band 3, Band 20
WCDMA (3G): Band 1
O2 UK (Telefónica):
4G LTE: Band 1, Band 3, Band 7, Band 20
WCDMA (3G): Band 1
GSM (2G): EGSM900, DCS1800
Vodafone UK:
4G LTE: Band 1, Band 3, Band 7
WCDMA (3G): Band 1, Band 8
GSM (2G): EGSM900, DCS1800
3 Ireland (Hutchison):
4G LTE: Band 12, Band 41
WCDMA (3G): Band 1
GSM (2G): Band 3, Band 8
EIR (Meteor):
WCDMA (3G): Band 1
GSM (2G): Band 3, Band 8
Vodafone Ireland:
4G LTE: Band 12, Band 41
GSM (2G): Band 3, Band 8
Telekom (T-Mobile):
4G LTE: Band 3 (1800 MHz), Band 7 (2600 MHz), Band 20 (800 MHz)
2G GSM: 900 MHz, 1800 MHz
Telefónica Germany (O2 & E-Plus):
4G LTE: Band 3 (1800 MHz), Band 7 (2600 MHz), Band 20 (800 MHz)
2G GSM: 900 MHz, 1800 MHz
Vodafone D2:
4G LTE: Band 1, Band 12, Band 41
WCDMA (3G): Band 1
GSM (2G): Band 3, Band 8
Bouygues Telecom:
4G LTE: Band 1, Band 12, Band 41
WCDMA (3G): Band 1, Band 8
GSM (2G): Band 3, Band 8
Free Mobile:
4G LTE: Band 3 (1800 MHz), Band 7 (2600 MHz), Band 20 (800 MHz), Band 28 (700 MHz)
3G UMTS: 900 MHz, 2100 MHz
2G GSM: 900 MHz
Orange France:
4G LTE: Band 1, Band 12, Band 41
WCDMA (3G): Band 1, Band 8
GSM (2G): Band 3, Band 8
SFR:
4G LTE: Band 1, Band 12, Band 41
WCDMA (3G): Band 1, Band 8
GSM (2G): Band 3, Band 8
Iliad Italia:
4G LTE: Band 3 (1800 MHz), Band 7 (2600 MHz), Band 28 (700 MHz)
TIM (Telecom Italia):
4G LTE: Band 1, Band 12, Band 27, Band 41
WCDMA (3G): Band 1, Band 8
GSM (2G): Band 3, Band 8
Vodafone Omnitel:
4G LTE: Band 1, Band 12, Band 41
WCDMA (3G): Band 1, Band 8
GSM (2G): Band 3, Band 8
Wind Tre:
WCDMA (3G): Band 1, Band 8
GSM (2G): Band 3, Band 8
Orange (Amena):
4G LTE: Band 1, Band 12, Band 41
WCDMA (3G): Band 1, Band 8
GSM (2G): Band 3, Band 8
Movistar (Telefónica):
4G LTE: Band 1, Band 12, Band 41
WCDMA (3G): Band 1, Band 8
GSM (2G): Band 3, Band 8
Vodafone Spain:
4G LTE: Band 1, Band 12, Band 29, Band 41
WCDMA (3G): Band 1, Band 8
GSM (2G): Band 3, Band 8
KPN:
4G LTE: Band 1 (2100 MHz), Band 3 (1800 MHz), Band 7 (2600 MHz), Band 8 (900 MHz), Band 20 (800 MHz)
3G UMTS: Band 1 (2100 MHz), Band 8 (900 MHz)
2G GSM: Band 3 (1800 MHz), Band 8 (900 MHz)
Vodafone NL:
4G LTE: Band 1 (2100 MHz), Band 3 (1800 MHz), Band 7 (2600 MHz), Band 8 (900 MHz), Band 20 (800 MHz)
3G UMTS: Band 1 (2100 MHz), Band 8 (900 MHz)
2G GSM: Band 3 (1800 MHz), Band 8 (900 MHz)
A: No. The radio detects the SIM card and automatically selects the optimal local network and APN profile.
A: The radio automatically falls back or defaults to available 4G LTE bands (or 2G where applicable) to maintain continuous PoC (Push-to-Talk over Cellular) service.