Does 48 SIM have mobile data speed throttling?

[ahtams3350]

I've been using a 48 SIM card in my router and noticed a clear speed throttling issue when downloading games on Steam:

Initially, my download speed is 500Mbps (60MB/s).
However, after downloading over 20GB, the speed suddenly drops to 180Mbps (22MB/s) and stays there.
When I change the APN to internet, the speed goes back to 500Mbps (60MB/s).
But again, after downloading over 20GB, the speed drops back to 180Mbps (22MB/s).
My 5G signal is very strong, so this is clearly not a signal issue but a throttling limit.

Is 48 SIM really "unlimited" as advertised, or is this just a misconfiguration on your end? Please clarify this and provide a solution! 🙏

[dalyer]

Your attached screenshots don't seem to display properly.

And it's not really clear what your APN is initially and what you're changing it to subsequently.

To configure your APN settings correctly on a phone text "APN" to 50048 and follow the instructions here:

• https://community.48.ie/t5/The-Newsroom/APN-Settings-step-by-step-guide-for-50048/m-p/60689

For a 4G/5G router use the same key post as a guide for manually configuring them.

Download speed fluctuations are not unexpected on mobile data.

And who's to say that some may not be caused by the router itself?

You'd probably need to see if the same behaviour occurs with another router or a phone.

You'll probably have to ask 48 support about their throttling policy - if any.

I doubt that anybody here on the Community Forum is going to have any clear insight on this.

To contact 48 support see the links in my signature below.

[ahtams3350]

Thanks for your response, but your explanation does not match my real-world test results.

I have conducted extensive testing using three different 48 SIM cards across multiple devices, including:
✅ An iPhone
✅ A 4G/5G router

The results are identical in all cases:

Download starts at 500Mbps (60MB/s)
After exactly 20GB, speed drops to 180Mbps (22MB/s) and stays there
Changing the APN to internet temporarily restores 500Mbps, but after another 20GB, speed drops again
This is NOT due to:
🚫 APN settings – I tested different (48months.liffeytelecom.com,internet,3broadband.ie)APNs, and the pattern remains unchanged
🚫 Random network fluctuations – The speed drop happens at the exact 20GB mark every time
🚫 My router or device – The same behavior happens on an iPhone and a different router

Conclusion:
This is clear throttling (speed restriction) after reaching 20GB of usage.

Your response suggests you are unsure whether 48 has a throttling policy, but my results indicate that a hard limit exists.

🔹 Can you confirm whether 48 does or does not throttle speeds after 20GB of usage?
🔹 If 48 claims to offer "unlimited data," why is this restriction in place?

I expect a clear and official statement from 48 about this policy. Otherwise, advertising "unlimited data" while imposing hidden limits is misleading.

Looking forward to an official response.

[dalyer]

> Can you confirm whether 48 does or does not throttle speeds after 20GB of usage?

No, I can't. You'll need to contact 48 support and ask them.

If you need to make a complaint in order to get an official response then see the last link in my signature below.