Intro
Ever run a speed test and thought, “Wait, I’m paying for 200 Mbps… why am I only getting 12?”
If you’re with Xfinity, you’re not alone. Upload speeds are where many customers see the biggest gap between what’s advertised and what they actually get.
In this guide, we’ll break down how to run an accurate Xfinity upload speed test, why your results may be disappointing, and what you can do about it.
👉 This article is part of our TestUploadSpeed.com Blog, where we dig into real-world internet performance — not just ISP marketing promises.
Why Upload Speed Matters More Than You Think
Most people obsess over download speed (Netflix, YouTube, browsing), but upload speed is what powers:
Zoom and Teams video calls
Cloud backups (Google Drive, Dropbox, iCloud)
Gaming (sending data to the server is just as important as receiving)
Streaming on Twitch or YouTube Live
If your upload is weak, all of the above suffer.
How to Run an Accurate Xfinity Upload Speed Test
Here’s how to do it without getting misled:
Step 1 – Use a Reliable Tool
You can use TestUploadSpeed.com (our tool is designed to focus on uploads).
Alternatively, Ookla Speedtest or Google’s built-in speed test works fine, but repeat it more than once.
Step 2 – Connect by Ethernet
Wi-Fi often cuts your upload speeds in half. Plugging in with Ethernet gives the real result.
Step 3 – Close Other Apps
Cloud sync, background downloads, even smart TVs can steal bandwidth. Run your test clean.
Step 4 – Compare at Different Times of Day
If it’s fine at 2am but terrible at 8pm, that’s not you — that’s Xfinity overselling bandwidth in your area.
What Xfinity Promises vs What You Get
Xfinity packages look like this (subject to market):
100 Mbps down / 10 Mbps up
200 Mbps down / 20 Mbps up
Gigabit: 1200 Mbps down / 35 Mbps up
Notice the problem? Even their “Gigabit” plan often only comes with 35 Mbps upload — tiny compared to download. That’s why running your own Xfinity upload speed test is so important.
Why Is My Xfinity Upload Speed So Slow?
Top reasons include:
ISP Throttling – Xfinity is known to limit upload bandwidth during peak hours.
Outdated Modem/Router – If you’re using the free rental gear, it might be the bottleneck.
Congested Area – Too many users in your neighborhood competing for bandwidth.
Plan Limits – You may literally be capped at 10–35 Mbps depending on your plan.
How to Fix Slow Xfinity Upload Speeds
Upgrade Your Equipment
A DOCSIS 3.1 modem and Wi-Fi 6 router can improve stability.
Use a VPN to Bypass Throttling
Xfinity can see your traffic and slow it down. A VPN hides it.
for calls, backups, and streaming.
www.TestUploadSpeed.com/cyberghost
Call Xfinity
Sometimes it’s as simple as a provisioning issue. Ask them to reset your line.
When to Switch Providers
If you consistently get poor upload results and Xfinity won’t help, it may be time to switch to fiber.
Providers like AT&T Fiber or Verizon Fios offer symmetrical speeds (same upload as download).
Conclusion
Running an Xfinity upload speed test regularly puts the power back in your hands. Don’t just take the ISP’s word for it — measure, compare, and demand what you’re paying for.
And if they don’t deliver? You now know your options.