QCI Overview
QCI (Quality of Service Class Identifier) is a priority system used by LTE/5G networks to manage traffic during congestion. Lower QCI numbers receive higher priority.
QCI Tier Breakdown
| QCI Level | User Type | Typical Service | Priority |
|---|---|---|---|
| QCI 5 | Premium postpaid | IMS signaling | Highest |
| QCI 6-8 | Postpaid customers | Standard data | High |
| QCI 9 | Standard postpaid/premium prepaid | General internet | Medium |
| QCI 9+ | Most MVNOs/prepaid | Deprioritized data | Low |
MVNO Reality
- Marketing claims vs actual QCI often differ
- Most MVNOs get QCI 9 regardless of marketing
- “Priority data” claims may mean:
- Slightly better than basic prepaid (still QCI 9)
- Limited high-priority data buckets
- Marketing without technical backing
Practical Impact
- Low congestion: QCI differences barely noticeable
- High congestion: QCI determines if you get usable speeds
- Time-sensitive: QCI matters most during peak hours (7-9 PM)
- Location-sensitive: Dense urban areas see bigger QCI impacts
Research Sources
Since carriers don’t publish QCI information:
- Reddit communities: r/USMobile, r/Verizon, r/ATT, r/tmobile
- HowardForums.com: Technical cellular discussions
- MVNO-specific forums: Real user testing and speed comparisons
- CellularInsights.com: Industry analysis
- User speed tests: Compare same location, different times
Testing QCI Priority
- Speed test during congestion (evening rush hour)
- Compare with postpaid users at same location/time
- Monitor consistency - true priority shows stable performance
- Check network selection - some MVNOs use specific network slices
Links: US Mobile Network Options, Signal vs Congestion Diagnosis