Cookies on the SIM Sherpa website

We use cookies to track which pages on our website readers visit most. This helps us understand which topics people find interesting, to write more articles about them.

You can accept these tracking cookies or choose to block them. You can change these settings at any time.

X close

✖ Tracking cookies deleted and blocked

Ok, we will not track your page views as you move around any part of the SIM Sherpa website. But we will use that one cookie to remember you don't want to be tracked.

Click here to unblock tracking cookies

X close

✔ Cookies accepted

Thank you for accepting cookies for the SIM Sherpa website. This will help us constantly improve our content.

If you ever want to change your cookie settings for our website, go to our Cookies page here.

Various logos of UK mobile networks

O2 custom plans: how they work, benefits and best-priced combinations

O2 logo and magnifying glass

We explain O2's new customisable phone plans, see what advantages they bring and calculate if certain combinations get you a better deal. SIM Sherpa is your trusty guide. Last updated: 24th September 2018

How O2's custom plans work

O2’s custom plans: what they’re about in a nutshell

O2 customisable phone plans banner

Tweak every part of the planRead O2's own guide

(opens in new window)

When they launched Refresh way back when, O2 were the first network to offer the flexibility of being able to upgrade your phone early, without paying hefty exit fees.

With their new custom plans, they’ve moved this flexibility on even further, letting you choose your own contract length anywhere between 3 and 36 months, and the upfront cost to pay.

They’ve also kept the early upgrades. And the ability to switch between data plans from month to month, which O2 call flexing your data.

Below, we take a quick look at what the pros and cons of O2’s build-your-own custom plans are, and show you how to pick the right deal for your needs.

Useful link: O2's full length guide to custom plans

The benefits: build-your-own deal to work with your budget

A phone and contract option sliders

Play with the upfront cost and contract lengthSee the phones

(opens in new window)

The point of O2’s customisable plans is to put you in control of how much you’re willing to pay, and at what point. Play with the settings to build a deal that works around your budget:

Choose a shorter contract length to bring down the time it takes to pay off your device cost, so you can upgrade again or leave altogether. This brings up the monthly cost.

Or choose a longer contract length to lower the monthly cost (because you’re spreading the total over more months). This means you’ll be tied to O2 for longer.

It’s a similar story with choosing the upfront cost you pay. Choose to pay more up front to reduce your monthly cost. Or elect to pay less and have a larger monthly bill.

Useful link: Change the data in your plan month-to-month

Disadvantage: there are 1000s of combinations of contract length and upfront costs per phone!

O2 custom plan calculator

Use O2's calculator on each phoneChoose a phone

(opens in new window)

The obvious problem that O2’s custom plans brings is that you’ve now basically spoilt for choice. The more options we have, the harder it is to commit to one.

Per phone, there’s now 33 different contract lengths you can choose. And anywhere up to 100 different amounts you can pay up front for your device.

Multiply those together and you’re getting into thousands of combinations for each phone alone. And each combination tweaks the monthly price you’ll pay.

So how do we consumers make sense of it and check if the combination we’ve chosen is the right one and we’re not getting a bad deal? The next section has the answers!

Useful link: See latest O2 phone pricing

Calculating the best prices

The total price of the phone always stays the same

Device cost slider and phone

Same total device cost, different contract lengthsO2's full guide

(opens in new window)

Read O2’s guide here which explains that their phone deals are made up two parts, a loan for your phone (paid off monthly until it’s gone) and a monthly plan with your mins, texts and data.

It’s crucial to know when you’re looking at O2’s custom plans that the total amount you’ll pay for the device stays the same, no matter which contract length and upfront cost you choose.

The monthly cost of your airtime plan (your minutes, texts and data) also stays the same, however much you fiddle with the device cost. It gets added on top to make your total price.

Once you know these two facts, it’s a bit of a relief:

There’s no magic combo of contract length and upfront cost where the total device cost falls, and you can’t get pick a ‘wrong’ combo and pay too much. So what are your options?

Useful link: Read all benefits to O2's custom plans

Shorter contract lengths: more flexibile, higher monthly cost

A short contract option

You'll pay off the device in bigger chunks

It might sound obvious but if you choose a shorter contract length, you’re going to pay off the device cost more-quickly. And at that point you’re free to make your next move.

The phone is yours, and you can choose either to upgrade to a new phone (keeping your old one too) and take out a new phone deal, switch to SIM only, or leave O2 entirely.

It also means you’ll be tied in for fewer months paying O2 for the minutes, texts and data plan (you can’t leave this before you’ve paid off the device).

Obviously when you choose a shorter contract, the total cost of the phone is spread over fewer months, so this option does increase your monthly cost (although not the total cost).

Useful link: O2's help section on credit agreements

Longer contract lengths: reduced monthly cost, less flexible

Longer contract option

Spread the same cost over more months

If you play with the sliders, you’ll see that the shorter time you pick to pay of the phone, the higher the monthly cost will be. The monthly cost can get intimidating quite quickly.

So if you’ve got a particular monthly budget for your mobile phone contract, you can pick a longer deal that spreads the device cost over more time. More months means the monthly payment is lower.

It’s worth noting though that, by extending the amount of time you take to pay off the phone, you’re also tied in to paying the monthly airtime plan (mins, texts, data) too.

Because we’d argue O2’s plans tend to be pricier than other networks, you are making the total cost of the whole deal higher by missing the opportunity to switch to a cheaper deal earlier.

Useful link: Compare phone contracts from all networks

Our verdict on O2's custom plans

Best strategy: pick the shortest deal you can easily afford

O2 Pay Monthly phone range

Only pick a contract you can affordO2's phone range

(opens in new window)

If the overall aim is to reduce the amount of money you pay to O2 over the course of your contract, it’s best to pick as shorter overall deal as you can afford on a monthly basis.

That way, even though the total device cost will stay the same, there will be fewer months where you’re tied to paying O2 for your minutes, texts and data. So the total combined cost is lower.

Do not stretch yourself though. You want a deal that’s affordable on a monthly basis. You don’t want ever to miss payments because you’re short of cash one month. This is bad for your credit rating.

The same applies for upfront costs. We’d aim to be borrowing as little as possible. Pay as much up front as you can afford. That way you’re on the hook for less for the rest of the contract.

Useful link: Pick a phone at

SIM Sherpa can help you find your next SIM only deal

network logos