Best Three Add-Ons – How To Get More Data For Less!


Best Three Add-Ons – Get More Data For Less!

If you have a PAYG SIM from Three, you should definitely check out Three’s add-ons if you want more data for not much money…


Pay as You Go SIM plans (PAYG) are great if you’re on a budget or you don’t use your phone too much. They’re also brilliant if you’ve bought your phone outright or are running an older phone you’ve already paid for.

But if your current PAYG isn’t quite cutting the mustard, and you’re with Three, you can access a whole load of add-ons that’ll make your PAYG plan way more useful, especially if you’re using more data than you initially thought you needed.

Best Three Add-Ons Detailed: Our #1 Picks For Right Now

[ninja_tables id=”130202″]


Not Sure What an “Add on” Is? Here’s A Quick Explanation

What is an add on? At Three, you can add “extras” onto your PAYG account – extras like more data, more minutes, or things like roaming. Add-ons vary in price, depending on what you’re after. But they are all fairly cost-effective, as you can see above in the table.

Best Three Add-On For Data

If you’re running a PAYG SIM from Three, the absolute best add-on you can get right now is the Monthly Boost Unlimited add-on. This add-on will give your truly unlimited data for one month. And it will only cost you £15 a month. That’s great value for money, especially since you can use the data to connect your phone to your PC/Laptop and tablet.

The next best add-on, if you don’t need loads of data, would be Three’s 6GB Monthly Boost Add-On. This add-on costs £8 and will get you an additional 6GB of data per month on top of your PAYG’s existing data allowance. If you’re a light user, 6GB of data (plus your PAYG’s existing data allowance) should be more than enough to get you through a month.

Each of Three’s add-ons will last for one billing month unless otherwise stated. You can choose to keep the add-on in place or just use it for one month. If you’re using the unlimited data add-on, which costs £15, you could use it to test how much data you get through in any given month.

If it is less than 10GB, for instance, you know that you could almost certainly get by with the Three’s 6GB of Monthly Data add-on, as that, combined with your PAYG’s data allowance, should give you around 11GB to 12GB of data per month. And the 6GB add-on is quite a bit cheaper than the £15 unlimited data add-on.

Three Add-On For Calling Aboard

If you have family and friends overseas, Three has a couple of add-ons that will allow you to make international calls from your phone without the MASSIVE costs normally associated with them.

Right now, there are two options for calling aboard add-ons, and they are as follows:

If you make a lot of calls aboard, it is probably worth going with the Call Abroad Unlimited plan, as it will give you unlimited calls overseas for just a tenner per month. And that, again, is really good value for money.

How Do I Buy Three Add-Ons?

If you’re on a Pay As You Go plan, you’ll need to make sure you have enough credit in your account to convert it into one of the above-listed add-ons. For instance, if you have £20 credit in your account, you could convert that money into the Unlimited Data add-on and still have £5 leftover.

If you’re a pay monthly customer with Three, the cost of your add-on will simply be added to your bill at the end of the month.

You can buy and activate add-ons inside the My3 app which, if you don’t already have it installed on your phone, can be downloaded via the Google Play Store or the App Store. And the app itself will run even if you don’t have any data left over, so you can always top-up, even if you’re running on fumes.

VIEW ALL Three Add-Ons OFFERS AND DEALS

Sharing is Caring!
KnowYourMobile
KnowYourMobile
@knowyourmobile.com@www.knowyourmobile.com

Your no bullsh*t guide to tech and tech trends, with a focus on data privacy and the open web

2,322 posts
0 followers

Latest Smartphone Releases


  • Xiaomi 15S Pro

    The Xiaomi 15S Pro didn’t come with a flashy launch, but it brings some seriously heavy hardware to the table. A custom 10-core chip, Leica-engineered cameras, and one of the brightest displays on the market

  • Samsung Galaxy S25 Edge

    At just 5.8mm thick, it’s one of the thinnest Android phones ever made—but don’t let the slim profile fool you. This phone is all flagship under the hood.

  • Nothing Phone (3a) Pro

    It’s got the same slick design and OLED display, but adds a periscope zoom camera and a 50MP front-facing shooter.

  • Nothing Phone (3a)

    The Nothing Phone (3a) nails the formula: give people what they actually want, keep the price low, and make it look cooler than anything else in its class.

  • Motorola EDGE 60 Pro

    With a bold design, flagship-like display, and surprisingly refined camera system, it’s one of the most interesting mid-range phones of 2025.

  • Google Pixel 9

    I’ve been using the Pixel 9 for a few weeks now, and honestly? It nails all the basics—and a bit more. Killer stuff all round!

  • Google Pixel 9 Pro

    I’ve used the Pixel 9 Pro as my daily device, and it’s hands-down the best balance of power, practicality, and photography you’ll find on Android right now.

  • OnePlus 13

    I’ve been using the OnePlus 13 as my daily driver for a few months now—and I’ve got to say, it’s easily one of the best Android phones I’ve tested this year.

  • Xiaomi 15 Ultra

    After using the Xiaomi 15 Ultra for over a week, I can confidently say: this phone is an absolute beast. It’s made for camera nerds, power users, and creators.

  • iPhone 16 Pro Max

    If you’ve been holding out for a truly complete iPhone, the 16 Pro Max delivers—hard. After using it daily, I won't be going back…

  • Google Pixel 9 Pro XL

    Big screen, big battery, and even bigger brains—this is the Pixel to get if you want Google’s best hardware and longest support.

  • Google Pixel 9a

    The Pixel 9a brings Google’s flagship-level smarts to a budget-friendly package, and it’s easily one of the best-value Android phones of 2025.

Best SIM-Only Plans & Deals


  • Boost Mobile Unlimited Premium Plan

    Boost’s top-tier option brings the heat: 50GB of premium data, hotspot, North America roaming, global talk & text, and $430 off select devices. All-in at $60/month with no contract.

    +

    Data: Unlimited (50GB premium speed)

  • Boost Mobile Unlimited+ Plan

    Level up with 40GB of premium data, hotspot access, global calling, and up to $300 in device savings. All for just $50/month. No contracts and flexible phone options included.

    +

    Data: Unlimited; Speed Caps After 40GB

  • Boost Mobile Unlimited Plan

    Start strong with 30GB of premium data, unlimited everything, and a killer intro offer: just $15/month for the first 3 months, then $25/month forever. No contracts. No fluff. Big value.

    +

    Data: Unlimited (Speed Caps Over 30GB)

  • iD Mobile 1 Month SIM-Only: 108GB

    Another high-data, low-cost option with no contract. 108GB for just £9, full 5G access, and the same goodies you get with 12-month deals.

    +

    Data: 108GB

  • iD Mobile 1 Month SIM-Only: 20GB

    The lowest price option. 20GB for £6 with all the same perks as pricier plans. Great if you don’t use much data and want to save every penny.

    +

    Data: 20GB

  • iD Mobile 1 Month SIM-Only: 110GB

    This plan gives you big data and zero commitment. 110GB for just £10 with all perks intact. If you need more data but want the freedom to cancel, this is the one.

    +

    Data: 110GB

  • iD Mobile 1 Month SIM-Only: 60GB

    More data, same price. For just £8/month, you get 60GB on a no-strings 1-month rolling plan. Ideal for users who stream often but don’t want long commitments.

    +

    Data: 60GB

  • iD Mobile 1 Month SIM-Only: 40GB

    Perfect if you want full flexibility. You get 40GB and all of iD Mobile's perks with no lock-in, annual increases, or setup fees. Great for short-term users.

    +

    Data: 40GB

  • iD Mobile 12 Month SIM-Only: 60GB

    One of the best pound-per-GB plans around. You get 60GB for £8 with £25 cashback, which means you’re effectively paying closer to £6/month. Includes roaming and data rollover.

    +

    Data: 60GB

  • iD Mobile 12 Month SIM-Only: 108GB

    This deal gets you a healthy 108GB of 5G data for less than a tenner, with no upfront costs and £24 cashback. All the perks are included too: data rollover, roaming, and loyalty rewards.

    +

    Data: 108GB

  • iD Mobile 12 Month SIM-Only: Unlimited Data

    This iD Mobile plan doesn’t just compete on price, it’s up there with the best of them. Unlimited everything, a year-long lock-in with no price rises, and £42 cashback straight to your pocket. It’s like getting nearly 3 months free.

    +

    Data: Unlimited, No Speed Caps

  • Mint Mobile 20GB Plan

    If you're looking to save some cash on your bills, this plan is an awesome option. You'll get 20GB of data per month and 20GB hotspot data allowance. For moderate to heavy users, that should be more than enough. I seldom use more than 10GB of data a month, and I'm always using my phone

    +

    Data: 20GB