How to Check If Your SIM Supports VoLTE After New Zealand’s 3G Shutdown
NZ networks are retiring 3G. If your SIM doesn’t support VoLTE, you may suddenly lose calling while mobile data still works.
Here’s how to check if your SIM, phone, and plan are actually ready — and what we do at EziRepair when they’re not.
1. VoLTE-related “No Service” cases are now one of our most common repairs.
Since NZ networks began phasing out 3G, we’ve seen a large spike in customers losing calling despite having full 4G or even 5G signal.
Many assume the phone is faulty — but often the real issue is an old SIM, an overseas SIM, or a plan that doesn’t have VoLTE provisioned.
We diagnose these daily across both Christchurch and Auckland branches.
2. Full bars but calling fails? That usually means your SIM isn’t VoLTE-ready.
After 3G shutdown, phones can show a strong 4G/5G signal but still fail calls.
That’s because older SIM cards relied on 3G for voice, even when data used 4G.
Now that 3G is going away, no VoLTE = no calls, even if mobile data works perfectly.
3. Real VoLTE-related cases from our Christchurch & Auckland workshops
- ✅ Spark customer with a 10+ year-old SIM – 4G data OK, calls failed. New SIM fixed everything instantly.
- ✅ Imported Samsung A52 – VoLTE menu hidden due to overseas firmware; calls dropped on One NZ. Updated CSC + NZ carrier settings restored VoLTE.
- ✅ iPhone XR on a cheap MVNO plan – plan didn’t include VoLTE provisioning; upgraded plan, calling restored.
4. Technical breakdown: how to check if your SIM supports VoLTE
📱 Step 1 — Check VoLTE setting on your phone
- iPhone: Settings → Mobile Data → Mobile Data Options → Voice & Data → ensure VoLTE is ON.
- Android: Settings → Connections / Mobile Network → VoLTE calls or 4G Calling.
- If VoLTE toggle is missing → SIM or plan is likely outdated or unsupported.
📶 Step 2 — Make a test call on 4G
- Turn WiFi off and stay on 4G.
- Make a normal call.
- If the call connects and stays on 4G → VoLTE is working.
- If calling fails or drops to “Call Failed” → SIM or plan may not support VoLTE.
🔄 Step 3 — Try your SIM in another VoLTE-capable phone
- If it fails there too → the SIM is the issue.
- If it works there → your phone may have a hardware or firmware problem.
💳 Step 4 — Replace the SIM if it’s old
- Spark / One NZ / 2degrees store will give you a modern VoLTE-capable SIM.
- Old SIMs (5–15 years old) often fail after 3G shutdown.
At EziRepair, we test your device with our own carrier SIMs.
If our SIMs work but yours doesn’t, the problem is confirmed as SIM or plan compatibility — saving you unnecessary board repair costs.
5. Related guides you might find helpful
If your phone suddenly can’t make calls after the 3G shutdown, we can check whether it’s a SIM issue, a VoLTE issue, or a hardware problem.
We diagnose with multiple NZ SIMs, check VoLTE provisioning, and inspect for antenna or board faults.
📍 EziRepair Christchurch & Auckland
www.ezirepair.co.nz | ☎ Christchurch: 03 343 1078 | Auckland: 09 392 0039