Three 321 Pay As You Go Review: 3p/minute, 2p/text and 1p/MB Rates

February 8th, 2017

Three charges 3p/minute, 2p/text and 1p/MB on Pay As You Go, with optional All in One bundles available from £10/month.

Three 321 Pay As You GoIn the UK, Three charges just 3p/minute, 2p/text and 1p/MB on Pay As You Go. With there also being 150MB of free data each time you top-up until the 23rd May, this makes Three one of the best value mobile networks for Pay As You Go usage.

Three’s 321 tariff is particularly suited for light and occasional mobile users as the top-up doesn’t expire providing your SIM card remains active. For regular mobile users, optional All in One bundles are available from £10/month and roaming at no extra charge through the Feel At Home offer is also available.

In this article, we’ll review Three’s 321 Pay As You Go tariff. We’ll start by looking at the features of the tariff and how it compares to Pay As You Go offerings on other mobile networks. We’ll also look at handset availability, at the level of coverage you can expect and how you can keep your existing phone number when moving to Three.

Pricing & Tariffs

Pay As You Go Pricing

In the UK, Three has some of the lowest Pay As You Go rates of any mobile network. On their 321 tariff, phone calls cost 3p/minute, text messages cost 2p each and mobile internet costs 1p/MB.

Order Three Pay As You Go SIM Card »

The following table shows a list of Three’s standard rates on Pay As You Go:

Calling Rates:
Voice Calls 3p/minute (any network, any time)
Calls to Voicemail 3p/minute
Calls to Special Rate Numbers 45p/minute access charge
+ service charge from the company you’re calling
Messaging Rates:
Text Message (SMS) 2p
Picture Message (MMS) 40p
Video Message 40p
Internet Rates:
Mobile Internet 1p/MB

The prices in this table are stated for UK-to-UK only. If you’re roaming or making international calls, higher charges will normally apply. Source for pricing information:

On Three, your Pay As You Go credit will never expire providing you keep your SIM card active. You can make sure your SIM card remains active by using it for a chargeable activity at least once every six months.

150MB Free Allowance

You’ll get 150MB of free data each time you top-up.

A unique benefit of Three’s 321 tariff is the 150MB of free data each time you top-up. This is available on top-ups until the 23rd May 2017. The free data allowance lasts for up to 30 days and is added to your account each time you top-up your handset.

The minimum top-up is just £5 if you top up online through the My3 website. It’s £10 if you top-up elsewhere (e.g. by phone, in store or at a bank ATM).

All in One Bundles

For customers with significant usage, buying an All in One bundle can save you money compared to paying the normal 321 rates. A bundle will give you a certain allowance of minutes, texts and internet which can be used at any time over the next 30 days.

For instance, the £10 All in One bundle comes with 100 minutes, 3000 texts and 1GB of internet. This would cost £73 at normal 321 rates but is available for just £10 on an All in One bundle.

The following table shows All in One bundles currently available from Three:


The disadvantage of buying an All in One bundle is your allowances will only last for up to 30 days. Any unused allowances will then expire along with the bundle (for this reason, light users should remain on standard 321 rates).

Feel At Home

Customers on Three Pay As You Go can benefit from the ongoing Feel At Home offer. This gives you international roaming in 42 countries at no extra charge, including in most of Europe, the USA and Australia.

This makes Three a great choice if you occasionally travel abroad to other countries. You can use the SIM card to stay in touch with friends and family, and you can continue using your favourite applications like social media, instant messaging and maps.

To take advantage of the Feel At Home offer, you’ll need to have an inclusive allowance that you’re able to use when abroad. In practical terms, this means you’ll need to buy an All in One bundle (the allowances in that bundle can then be used when you’re abroad at no extra charge).

The normal UK out-of-allowance rates (3p/minute, 2p/text and 1p/MB) cannot be used when you’re travelling abroad. Instead, you’ll need to pay the out-of-allowance rates appropriate to that country.

Order Three Pay As You Go SIM Card »

Comparison to Alternatives

Three’s 321 rates are among the lowest in the UK.

We believe Three’s 321 Pay As You Go offering is a great value tariff if you’re a light or occasional mobile user. Three has super-low Pay As You Go rates, and you also get 150MB of free data each time you top-up.

If you’re a regular mobile user and if you’re likely to use more than 1GB of data per month, rival mobile networks may offer a better value deal (in particular, ASDA Mobile and giffgaff).

Pay As You Go Pricing

Three’s Pay As You Go pricing is among the lowest in the industry at just 3p/minute, 2p/text and 1p/MB. It provides a great value way of using your smartphone, without the need to top-up every month or to buy 30-day bundles.

In the following table, we compare Three’s Pay As You Go rates against rival mobile networks:

Network Calls (per minute) Texts (per SMS) Data (per MB)
Three 3p/minute 2p/text 1p/MB (150MB free with top-up)
ASDA Mobile 8p/minute 4p/text 5p/MB
EE 30p/minute 12p/text
giffgaff 15p/minute 5p/text 5p/MB
O2 5p/minute 5p/text 5p/MB
Tesco Mobile 25p/minute 10p/text 10p/MB
Vodafone 30p/minute 14p/text £2/day for 50MB

For more information, please see our full comparison of Pay As You Go rates.

£10 per month bundles

10 Pound NoteFor £10/month, Three offers the All-in-One 10 bundle with 100 minutes, 3000 texts and 1GB of internet.

For the same price of £10/month, better value bundles are available on other mobile networks.

At present, our recommended deal is the £10 bundle from ASDA Mobile. This gives you 600 minutes, unlimited texts and 2GB of internet. ASDA Mobile makes use of 2G, 3G & 4G coverage from EE.

Alternatively, giffgaff has a £10 goodybag with 500 minutes, unlimited texts and 2GB of internet using coverage from the O2 network.

ASDA Mobile600Unlimited2GB£10.00

£15 per month bundles

Unfortunately, Three doesn’t currently offer a £15 Pay As You Go bundle. For customers wanting more than the 1GB of data included the £10 bundle, the next available option will be the £20 bundle with 12GB of data. If this is likely to be overkill for your usage, getting a £15 bundle from rival mobile networks could be a good half-way house.

At present, giffgaff offers 1000 minutes, unlimited texts and 5GB of data for £15/month. Alternatively, ASDA Mobile also has a competitive offering with 1000 minutes, unlimited texts and 5GB of data for £15.

ASDA Mobile1,000Unlimited5GB£15.00

£20 per month bundles

20 Pound NoteThree has a £20/month All-in-One bundle with 300 minutes, 3000 texts and 12GB of internet.

For the same monthly price, giffgaff offers a £20 goodybag with 2000 minutes, unlimited texts and always-on data. This gives you unlimited downloads with 4G internet and tethering on the first 6GB per month.

ASDA MobileUnlimitedUnlimited8GB£20.00

For a more detailed comparison, please see our in-depth article on Pay As You Go bundles.


You can order a free Pay As You Go SIM card from Three’s website which will slot inside your unlocked smartphone to give you the benefits of the tariff.

If you’d like to keep your existing smartphone, you may find it useful to see our guides on unlocking an iPhone and unlocking a Samsung Galaxy smartphone. The SIM card from Three will work in any unlocked handset, providing it supports either 3G or 4G coverage.

If you’d like to purchase a brand new smartphone, you can buy an unlocked handset from any online retailer (our recommendation is currently to buy a Moto G). A range of Pay As You Go handsets can also be purchased directly from Three, which can save you the hassle of having to buy your handset elsewhere.


3G & 4G Coverage

Three offers 97% population coverage on 3G and 4G.

In the UK, Three offers 97% population coverage on 3G and 4G.

Before joining Three on their 321 Pay As You Go service, we strongly recommend checking the coverage in your area. You can do this by entering your postcode on Three’s online coverage map.

Check Three Coverage Map ( »

Unfortunately, Three does not provide any 2G coverage. For this reason, if you’re using a 2G-only handset, you won’t be able to receive any coverage from Three. Instead, you should consider an alternative network that also provides 2G coverage. At present, our recommendation is ASDA Mobile (they charge 8p/minute and 4p/text, and have 99% population coverage from EE).

For more information about the coverage on different mobile networks, please see our in-depth guide to mobile phone coverage in the UK.

Tethering & Personal Hotspot

The use of tethering is not permitted on Three Pay As You Go.

Tethering or personal hotspot refers to the process of sharing your smartphone’s internet connection with other devices (for instance, with your laptop or tablet).

Unfortunately, it’s not possible to tether on Three Pay As You Go. This is stated in their Pay As You Go terms and conditions:

Use your SIM in your 3G smartphone only.

When using data, tethering a phone to a laptop for internet use, using the SIM in a Mobile Broadband Device or using hotspot functionality is not included.

If you’d like to tether or use personal hotspot on Three, you’ll need a Pay Monthly Advanced price plan. Alternatively, you can choose another Pay As You Go network that does allow you to tether from your smartphone. For more information, see our full guide to tethering on UK mobile networks.

International Roaming

On Three, international roaming is enabled automatically for all customers on Pay As You Go.

For customers visiting one of 42 countries (including most of Europe, the USA and Australia), it’s possible to use your SIM card abroad at no extra cost through the Feel At Home offer. To qualify, you’ll need an All-in-One bundle which will give you allowances available to be used when abroad. For more information, you can find out about international coverage on the Feel At Home offer.

If you’re visiting a country that’s not covered by the Feel At Home offer, additional charges may apply for your usage when abroad. Please see the Three website for full details about their international coverage.

Keeping Your Phone Number

Transfer Phone Number to Three

It’s a straightforward process to transfer your phone number to Three.

If you’re joining Three Pay As You Go from another mobile network, it’s a straightforward process to keep your existing number.

Once you’ve ordered your Pay As You Go SIM card from Three, you should contact your old mobile network to ask for a PAC Code. This will authorise the transfer of your phone number to Three. Your old mobile network must provide a PAC Code free of charge within two hours of your request.

When your new SIM card arrives from Three, you can fill out this form on Three’s website. After you submit your PAC Code, your phone number transfer will be scheduled by Three, normally for the next working day.

For step-by-step instructions on transferring a phone number to Three, please select your current mobile network from the drop-down menu below:

PAC Code Finder: Transfer Your Phone Number to Three

Your current network provider:

  More Options

For more information about transferring a phone number between mobile networks, please see our guide to using a PAC Code.

More Information

For more information about Three’s Pay As You Go service, please see their official website. You can also order a free Pay As You Go SIM Card through their website.

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About Ken

Ken Lo

My passion is helping people to get the most out of their mobile phone. I've been blogging at Ken's Tech Tips since 2005.

Aside from writing about mobile technology, my interests are in software development, digital marketing and physics. Outside of the blog, I work with numerous technology companies helping them to explain their product and helping them to market it to consumers. Please get in touch for more information.

Your Comments

We'd love to hear your thoughts and any questions you may have. So far, we've received 108 comments from readers. You can add your own comment here.

  1. John said:

    Tethering wirks just fine with 321

    1. Ken replied:

      Hi John,
      Thanks for your comment. Technically speaking, I think it’s against the terms and conditions to tether on Three’s Pay As You Go service. I know Three does make use of some tethering detection, but I’m not sure how strictly they apply this and how regularly they do it.

  2. Emgee said:

    I use 3 on payg, but 3 are going to remove the free 150mb with the top up from May 23rd. This is a good feature. When I’ve run out of data, I can go on to the 3 site and purchase a monthly internet add-on, without using credit to do it. Now it’ll cost me to get add-ons, unless I can get to a free wifi place.

    1. Ken replied:

      Hi Emgee,
      Thank you for the heads up about this, and it’s a real shame that Three are removing the 150MB free allowance. I’ve updated the article above to reflect this information. I believe customers will instead receive a (measly) 10MB of free data when they top-up their account in the future.

      1. Emgee replied:

        Thanks for the information about the 10Mb allowance. That information wasn’t included on the text from Three. At least I’ll be able to log on to the website to buy the add-on after topping up.
        I’m not a heavy user, in general, except when I have some research to do. The 150 Mb often used to last several days, which has saved me money over the last nine years (as a Three payg customer) by delaying the beginning of the 30 day period.

  3. William Grierson said:

    In your description for £10 bundles you say Asda has 1.5Gb and GiffGaff has 1Gb yet in the table it shows 3.5Gb and 2Gb respectively.
    The same as in the description for £15 bundles Asda 3Gb and GiffGaff 4Gb but in the table it shows 5Gb for both.

    1. Ken replied:

      Hi William,
      Many thanks for the heads up about this! giffgaff updated their bundles very recently, so the £10 goodybag now includes 2GB of data (rather than the 1GB per month it previously contained). With regards to ASDA Mobile, they’re offering a time-limited promotion where customers get 2GB/month of extra free data until the 27th June 2017.
      I’ve just updated the information above to better reflect this (the comparison tables across the website are updated automatically, but sometimes I miss out on copy/content changes).
      Thanks again!

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