Xfinity's 1.2TB Data Cap, Explained
Most Xfinity plans in most states include a 1.2TB (1,200 GB) monthly data allowance. Go over it and Comcast bills $10 for each additional 50GB block, capped at $100/month in overage fees before switching you to unlimited billing for the rest of that cycle in some markets.
What Actually Uses 1.2TB
| Activity | Approx. Data per Hour | Hours to Hit 1.2TB (this activity alone) |
|---|---|---|
| 4K streaming (Netflix, single stream) | 7 GB/hr | ~171 hrs |
| 1080p streaming | 3 GB/hr | ~400 hrs |
| Cloud gaming (GeForce NOW, 1080p) | 4.5 GB/hr | ~267 hrs |
| Video calls (Zoom/Teams, group) | 1.5 GB/hr | ~800 hrs |
| Large game downloads (100GB titles) | — | 12 downloads |
For most single-stream households, 1.2TB is generous. The cap becomes a real risk with 4+ simultaneous 4K streams, a household that games and downloads large titles frequently, or anyone running a home server/NAS with cloud backup.
How to Track Your Usage
The xFi app shows real-time usage under "Data Usage" — check it monthly, not just when you get a warning email. Comcast sends alerts at 75%, 90%, and 100% of your allowance, but by the 90% alert you may already be days from overage.
How to Avoid the Fee Entirely
- Add xFi Complete ($25/month bundle) — includes unlimited data plus the gateway rental, often cheaper than paying overage fees most months.
- Some states have no cap at all — Comcast doesn't enforce the 1.2TB limit in the Northeast markets due to state-level regulation. Check your account's data usage page to confirm whether your specific address is capped.
- Request a one-time courtesy waiver if you go over for the first time — Comcast frequently grants this on request, once.