With 3G being switched off, VoLTE (Voice over 4G) is the new thing all the kids are talking about.
It lets you make clearer, faster voice calls over the 4G network, so you won't miss out when 3G is gone. Check below to see if your phone supports VoLTE.
Alcatel - 
Alcatel 4G Mifi ✅
Alcatel R228T 4G Mifi ✅
Apple - 
iPhone 6 ✅
iPhone 6 Plus ✅
iPhone 6S ✅
iPhone 6S Plus ✅
iPhone 7 ✅
iPhone 7 Plus ✅
iPhone 8 ✅
iPhone 8 Plus ✅
iPhone SE (2) ✅
iPhone XR ✅
iPhone XS ✅
iPhone XS Max ✅
iPhone X ✅
iPhone 11 ✅
iPhone 11 Plus ✅
iPhone 11 Pro ✅
iPhone 12 ✅
iPhone 12 Mini ✅
iPhone 12 Pro ✅
iPhone 12 Pro Max ✅
iPhone 13 ✅
iPhone 13 Mini ✅
iPhone 13 Pro ✅
iPhone 13 Pro Max ✅
iPhone 14 ✅
iPhone 14 Plus ✅
iPhone 14 Pro ✅
iPhone 14 Pro Max ✅
iPhone 15 ✅
iPhone 15 Plus ✅
iPhone 15 Pro ✅
iPhone 15 Pro Max ✅
iPhone 16 ✅
iPhone 16 Plus ✅
iPhone 16 Pro ✅
iPhone 16 Pro Max ✅
iPhone 17 ✅
iPhone Air ✅
iPhone 17 Pro Max ✅
Dell - 
Latitude 5320 Laptop ✅
Fairphone - 
Fairphone 5 ✅
Google - 
Pixel 6 ✅
Pixel 6 Pro ✅
Pixel 6a ✅
Pixel 7 ✅
Pixel 7 Pro ✅
Pixel 7a ✅
Pixel 8 ✅
Pixel 8 Pro ✅
F10 Fold ✅
Pixel 8a ✅
Honor - 
Magic 4 Lite ✅
Magic 4 Pro ✅
70 5G ✅
X8 5G ✅
X6 4G ✅
70 Lite 5G ✅
90 5G ✅
90 Lite 5G ✅
90 Smart 5G ✅
Magic 5 Lite 5G ✅
Magic 5 Pro 5G ✅
Magic Vs 5G ✅
Magic V2 5G ✅
Magic 6 Lite 5G ✅
Magic 6 Pro 5G ✅
200 Lite 5G ✅
Huawei - 
P40 Pro ✅
P40 Pro Lite ✅
Motorola - 
G8 Power ❌
E6 Plus ✅
G8 Plus ✅
G82 5G ✅
Play ❌
Razr 40 ✅
Razr 40 Ultra ✅
Edge 40 ✅
G34 5G ✅
G04 4G ✅
Edge 50 Pro ✅
Nokia - 
2.2 ❌
C02 ✅
G22 ✅
Samsung - 
A03 ❌
A03s ✅
A04s ✅
A10 ✅
A12 ✅
A13 ✅
A14 5G ✅
A14 4G ✅
A15 4G ✅
A20e ✅
A21s ✅
A22 5G ✅
A23 5G ✅
A25 5G ✅
A32 5G ✅
A33 5G ✅
A40 ✅
A50 ✅
A51 ✅
A52s 5G ✅
A53 5G ✅
A54 5G ✅
A55 5G ✅
A7 ✅
A70 ✅
A71 ✅
A90 ✅
Fold 3 ✅
Flip 3 ✅
Fold 4 ✅
Flip 4 ✅
Flip 5 ✅
S20 ✅
S20 FE ✅
S20 FE 5G ✅
S21 ✅
S21 FE ✅
S22 ✅
S23 ✅
Note 20 ✅
Note 20 Ultra ✅
S22 Ultra ✅
S23 Ultra ✅
Sony - 
Xperia 1 IV ✅
Xperia 5 IV ✅
Xperia 10 IV ✅
Xperia 10 III ✅
Xperia 10 ✅
Xiaomi - 
Redmi Note 10 ✅
Redmi Note 11 ✅
Redmi Note 11 Pro ✅
Redmi 9 ✅
Poco F3 ✅
Mi 11 ✅
Mi 11 Lite ✅
Mi 11 Ultra ✅
Mi 12 Lite ✅
Mi 12 Pro ✅
As we use Three, you can use their online checker here to see if 3G is being turned off in your area