Three UK Suddenly Introduces Mobile Broadband Speed Caps UPDATE

Customers of mobile network operator Three UK (VodafoneThree) were given quite the surprise yesterday afternoon after the provider suddenly notified them, without any prior warning, that they would be introducing mobile broadband (4G, 5G) speed caps of between 25Mbps and 100Mbps (Megabits per second) across various plans from the same date.

So far as we can tell from the various emails and forum posts that ISPreview has received since Sunday afternoon. New customers looking to take out most of the operator’s new Pay Monthly and Mobile Broadband plans will now be subject to a maximum speed cap of “up to” 100Mbps (in practice this will most typically reflect download performance, since uploads rarely reach that high).

By comparison, those taking out a new Pay As You Go (PAYG) plan will be capped to a speed of 25Mbps, “except in the following MBB Data cases where we offer speeds of up to 50Mbps: MBB Data Only Data packs [and] MBB Data at our Standard rates.”

The catch with PAYG is that there isn’t a long contract involved and so the speed cap will be applied unless you keep an existing Auto-renew Data Pack active (see below). Further details can be found in the operator’s related Price Guides here, here and here (PDFs – dated from 19th April 2026).

Three’s Text Message to PAYG Customers:

“We wanted to let you know about upcoming changes to our network. From 19 April, download speeds will be capped at 50Mbps for new customers. But good news – if you keep your current Auto-renew Data Pack active, you will continue enjoying uncapped speeds.”

The message appears to be that many existing customers will be unaffected by this change, although over time such users will inevitably re-contract or upgrade and may thus still eventually become subject to the cap. But what isn’t so clear right now is why Three UK has introduced the change, although many are already speculating that it could be a negative result of last year’s merger with Vodafone (some of Voda’s mobile plans have similar caps).

Naturally this change probably won’t be something that the majority of Smartphone users will really notice, not least because mobile broadband performance can already be highly variable and doesn’t always manage to reach the level of the cap. But experiences do vary between locations and there will also be those who use their mobile data link for home broadband, which are more likely to notice.

We’ve asked VodafoneThree to comment and will report back if they respond.

UPDATE 9:31am

We’ve received a reply from VodafoneThree, but this only confirms what we’ve reported above and ducks the question of why they’ve introduced a cap, when one didn’t exist before.

A Spokesperson for VodafoneThree told ISPreview:

“From 18th April, we are launching new speed tiers on Three’s mobile network, which will enable new and upgrading customers to choose the data speeds which best match their needs.

Pay Monthly mobile customers will have access to Everyday Speeds of up to 100Mbps – faster than the average UK mobile download speed (72Mbps* [based on the Ookla Speedtest Global Index, Dec 2025]) – allowing customers to access superfast speeds for seamless browsing, streaming and sharing. For those who want the best possible network speeds, they can choose from a flexible, monthly Full Speed Add-on or Lite+ with Full Speed Add-on included for the duration of the plan.

Pay As You Go mobile plans will offer speeds of up to 25Mbps as standard, or up to 50Mbps for those on Auto Renew Data Packs.

Mobile Broadband customers on pay monthly plans will also have access to Everyday Speed of up to 100Mbps, with the option to purchase a Full Speed Add-on. Pay As You Go Mobile Broadband plans will offer speeds of up to 50Mbps.”