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Comparison

Sky Mobile vs SMARTY: Which SIM-Only Deal Is Better?

Short answer: Sky Mobile makes sense if O2 works better where you need signal or an eligible Sky Piggybank balance will save you buying extra data. SMARTY makes sense if Three works well, you want prepaid rolling payments, included EU roaming or a qualifying Group discount. Neither wins automatically on price: Sky has both 24-month and 30-day SIM options, while SMARTY's standard plans have no two-year minimum term.

Key differences: Sky uses O2 and banks unused data on eligible capped plans for up to 12 months. SMARTY uses Three, normally includes EU roaming subject to its fair-use limit, and offers Mix & Match or Everyone Unlimited Group arrangements. Both offer 5G and eSIM on compatible devices. The real choice is between the networks that work at your postcode, the data you actually use and the cost of staying or leaving.

Ready to compare? Check Sky Mobile deals on DealPriceCheck and SMARTY's rolling SIMs. If you already know your data use, go straight to the Sky 25GB 24-month card, Sky 25GB rolling card or SMARTY 20GB rolling card. Use Full plan details, then View Deal only after comparing the actual commitment and charges.

Sky Mobile vs SMARTY at a glance

Buying questionSky MobileSMARTYWhat matters in practice
Which network?O2ThreeIndoor coverage at your own postcode is more useful than a nationwide slogan.
How long is the commitment?Selected 24-month SIMs and a 30-day rolling option in our cataloguePrepaid, rolling one-month plansCompare the actual term shown on each card, not just the brand.
What happens to unused data?Eligible capped-data plans save unused GB in Sky Piggybank for up to 12 monthsOrdinary new plans do not have Sky-style rollover; discontinued Data Discount plans are a separate legacy productA data bank only adds value if you use or redeem it.
Can I share savings across several SIMs?Piggybank data can be shared with eligible SIMs on the same accountEligible Groups can reduce costs through Mix & Match or a separate Everyone Unlimited arrangementThe two group models work differently.
How do EU roaming charges work?Roaming Passport Plus is normally a paid 24-hour pass in eligible destinations; Republic of Ireland is treated differentlyIncluded EU roaming on eligible phone plans, normally limited to the smaller of your UK allowance and 12GB; Ireland is an exception to that capCount travel days and data before choosing.
5G, eSIM and calls over Wi-Fi?Available subject to phone, plan, settings and coverageAvailable on compatible devices; check particular handset/plan eligibilityNeither provider guarantees identical features on every phone.

Quick decision: Choose SMARTY if you need to be able to leave after a billing cycle, travel regularly to eligible EU destinations or manage multiple eligible SIMs under a Group. Choose Sky if O2 is the better working network at your home or office, or a particular Sky SIM and its Piggybank give you more useful value over the period you expect to stay. If both networks work, the full payment schedule decides more than either company's marketing headline.

Which actual Sky and SMARTY SIMs should you compare?

Both catalogues contain multiple plans, but their allowances do not line up neatly. The sensible comparison is between the smallest plans that cover your typical usage, with the larger allowance treated as an added benefit rather than proof of better value.

The following cards represent real choices available through our catalogue. Compare allowances and commitment first; the separate cost table below explains why Sky’s starting price must not be mistaken for a fixed two-year bill.

Your likely usageSky plan on DealPriceCheckSMARTY plan on DealPriceCheckBest question to ask
Light phone use, usually below 10GBSky 10GB, 24 monthsSMARTY 5GB rollingAt our check both started at £6 per payment, but Sky tied that price to 24 months; would you actually use the extra 5GB?
Around 15–25GBSky 25GB, 24 monthsSMARTY 20GB rollingIs 20GB enough, and what is keeping the option to leave worth?
Around 30–50GBSky 50GB, 24 monthsSMARTY 40GB rollingWould you use Sky's extra 10GB or bank the excess?
Heavy use, routinely above 60GBSky 75GB, 24 monthsSMARTY 100GB rollingIs 75GB actually enough, and how much do you value a changeable plan?
Unlimited UK useSky Unlimited optionsSMARTY Unlimited rollingIs Sky Piggybank irrelevant on Unlimited, and what do hotspot terms permit?
A short stay or a network trialSky 25GB, 30-day rollingSMARTY 20GB rolling or 40GB rollingDoes the exact Sky rolling price justify choosing O2 rather than Three?

The Sky links above lead to DealPriceCheck's individual plan details, where the final View Deal button takes you to the provider. SMARTY has separate Group checkout rules: choosing an ordinary SMARTY 40GB plan does not automatically create a Group or qualify you for a discount.

Small-data users: why a cheaper Sky contract is not automatically safer

Sky's low-data 24-month card can appear attractive alongside a modest SMARTY plan. Yet a headline price comparison is incomplete if you are uncertain about reception or likely to relocate. SMARTY's shorter commitment may let you test Three in the places that matter. Sky's rolling card may let you test O2 without taking the 24-month offer. A £1 or £2 saving on a fixed contract is of little use if a poor signal forces you to pay for a second SIM.

At our check, Sky 10GB on a 24-month contract and SMARTY 5GB rolling each started at £6 per payment. Sky offered twice the UK data at the same initial price; SMARTY offered the ability to stop or change after the rolling period. The Sky 10GB card does not provide a verified months 13–24 price, so it cannot establish a two-year saving. If 5GB covers your normal use, the relevant benefit to value is either Sky's extra headroom/Piggybank or SMARTY's freedom to leave, not the headline number alone.

Mid-data users: Sky 50GB versus SMARTY 40GB

This is the clearest practical comparison for a regular user who streams some video, listens to music and occasionally tethers a laptop. Sky includes more data in the named example, while SMARTY offers the option to change next month. Ask whether you actually crossed 40GB in any of your last three ordinary months. If not, Sky's extra capacity may mainly become spare GB; if your data use varies seasonally, that might still help through Piggybank.

Check the network first. If O2 is reliable indoors and Three is not, Sky's extra commitment may be tolerable. If Three works and you prefer no long obligation, SMARTY has a clear advantage before you even compare nominal cost per GB.

Check the real cards: Sky 50GB, 24 months · SMARTY 40GB, rolling.

Heavy-data users: more data can be worth less commitment

Sky's 75GB capped plan and SMARTY's 100GB rolling plan appeal to people who often use mobile video, downloads and a hotspot. They are not matched allowances. The right calculation is whether your busiest normal month stays below 75GB. If it does, 100GB may simply look impressive on a comparison table. If it does not, SMARTY's higher allowance and flexibility could save top-up hassle.

Neither is a substitute for verifying whether a router, long hotspot sessions or heavy fixed-broadband replacement use meets the plan's device and fair-use conditions. If your real requirement is unlimited data, compare unlimited SIM-only offers instead of declaring the largest capped plan good enough.

Sky vs SMARTY total cost: 12 and 24 payments, including promotions

The headline differences are often about commitment, not technology. A 24-month Sky plan may require you to continue paying even if you stop using it, and its advertised introductory rate may end during the minimum term. SMARTY normally takes payment in advance for a recurring monthly plan and lets you stop or change without that long minimum term. Sky also offers a 30-day option, so the fairest process is to compare three possibilities: Sky fixed term, Sky rolling, and SMARTY rolling.

Current-price examples: advertised amounts versus what you actually pay

A price-rise trap to avoid: the DealPriceCheck Sky cards show initial advertised charges and a base minimum cost, but Sky's own offer terms published at our October 2026 check show a second-stage price on several matching allowances. The provider's published promotion may not be identical to the offer reached through a particular affiliate link. Check the exact checkout summary; where a linked card does not identify the future payment schedule, do not treat its `minimum contract cost` as the complete payable total.

Plan or published offer checkedInitial paymentFirst 12 paymentsFirst 24 paymentsWhat the example means
Sky 10GB, 24 months£6/month on our card£72 if unchangedNot verifiedOur specific Awin card confirms the £6 starting rate but not the later charge; the displayed £144 base minimum must not be assumed final
SMARTY 5GB, rolling£6/renewal£72£144Conditional on 24 renewals at £6, with freedom to stop earlier
Sky 25GB, 24 months£10/month£120£288Sky's published promotion: £10 for 12 months, then £14 for 12 months; other contractual rises could apply
SMARTY 20GB, rolling£9/renewal£108£216Assumes unchanged renewal pricing
Sky 50GB, 24 months£11/month on our cardUnconfirmedUnconfirmedThe linked card's £264 base minimum does not disclose a verified full payment schedule; do not assume £11 for all 24 months
SMARTY 40GB, rolling£10/renewal£120£240Assumes unchanged renewal pricing
Sky 75GB, 24 months£14/month£168£432Sky's published promotion: £14 for 12 months, then £22 for 12 months; other contractual rises could apply
SMARTY 100GB, rolling£12/renewal£144£288Assumes unchanged renewal pricing
Sky 25GB, 30-day rolling£15 first month£202£406Sky's published promotion: £15 first month, then £17 for subsequent months, assuming no other changes; no obligation to keep renewing for 24 periods

Read these as dated examples, not checkout quotes. Sky's £288 for 25GB and £432 for 75GB are the mathematical totals of its publicly advertised staged promotions, before any additional permitted increase. Our affiliate-linked cards show the same starting allowances/prices but do not prove those exact staged terms apply to the Awin checkout. The 10GB and 50GB Sky cards have no independently confirmed full 24-payment schedule. SMARTY's totals simply multiply today's rolling prices and assume each renewal remains available at that rate.

Calendar comparison: The SMARTY cards are labelled 30-day rolling by DealPriceCheck, while SMARTY describes its service as one-month prepaid. Treat the table as comparisons of 12 or 24 payments, not identical periods of coverage. Twelve literal 30-day cycles cover 360 days; the exact renewal date and commitment come from the relevant checkout. Sky's 24-month minimum is a calendar-month commitment.

Worked comparison: a £1 headline difference can become £72

Sky's published 25GB fixed-term offer starts at £10, while our SMARTY 20GB rolling card starts at £9. In the first 12 payments the difference is £12 (£120 versus £108). If Sky's stated second-stage price of £14 applies and SMARTY still renews at £9, payments 13–24 cost £168 versus £108: another £60. Over 24 payments, £288 versus £216 = £72, before any other applicable price rises or extras.

You get 5GB more monthly UK data with Sky and eligible Piggybank rollover. Is that worth £72 plus a two-year commitment? It can be when O2 is clearly better at home or the extra data genuinely prevents top-ups. If Three works equally well and 20GB meets your needs, the rolling SMARTY option may be the more economical purchase. The real checkout may differ by promotion or sales channel, so verify the quoted Sky schedule before ordering.

What if you leave after six months?

At the starting rates, six Sky 25GB payments total £60 and six SMARTY 20GB payments £54. That £6 difference does not measure flexibility: after six months the SMARTY customer can generally stop future renewals, while someone on a Sky 24-month agreement may still face the minimum-term obligations and an early-termination charge. Request Sky's actual quote rather than multiplying the remaining months by a guessed price. Sky Mix can change your data plan, but does not end the contract term, and mixing may void a promotional offer.

For Sky's 50GB versus SMARTY's 40GB, the starting gap is £1 (£11 versus £10), but an honest 24-month comparison needs the full Sky checkout schedule. We cannot prove that £11 remains payable for the whole two years from the public card alone. Comparing a fabricated £264 fixed total against SMARTY's £240 would be misleading.

A second worked example: Sky’s own rolling deal

Our Sky 25GB 30-day card advertises £15 for the first period. Sky's current published standard rolling promotion moves to £17 per month after the first payment, rather than staying at £15. Twelve payments under that schedule would be £202 (£15 + 11 × £17), compared with £120 for the first 12 payments of Sky's published 25GB 24-month offer. The rolling premium over those 12 payments is therefore £82, not £60. If both were kept for 24 payments at those published stages, they would cost £406 and £288, a £118 difference before any additional changes. The rolling option avoids the two-year minimum term and can test O2 reception. Sky's overview says a 30-day rolling plan can be cancelled on 30 days' notice, while its individual promotional wording describes cancellation effective from the next billing date: follow the cancellation rule in your own agreement rather than assuming an immediate stop. These are two different Sky products, not a guaranteed choice of prices in the same checkout.

Buying rule: Before signing a long contract, work out the difference in costs over the months you are confident you will need the service. If the saving is small, freedom to stop can be the more valuable product feature.

Compare the same decision in the catalogue: Sky 50GB with 24-month commitment · Sky 25GB on a rolling plan · SMARTY 40GB rolling. Open Full plan details, then View Deal, and check the final purchase terms.

What Sky Piggybank gives you, and when it is worth paying for

Piggybank is Sky's most distinctive feature in this comparison. Eligible unused data on a capped Sky plan goes into an account balance rather than disappearing immediately at the end of that billing period. You can later withdraw whole gigabytes to eligible SIMs on the same Sky account or, subject to the rewards available, exchange saved GB for selected rewards.

There are important limits:

Example: a seasonal user versus a consistently light user

Imagine you choose a 25GB Sky SIM and use around 8GB during a quiet month. About 17GB might become available to bank, subject to the provider's calculation and the plan's eligibility. If you later work away from home and use 30GB in a busy month, you may be able to draw on saved data. That is a real use case for Piggybank.

Now imagine you use 8GB every single month. Paying for 25GB largely to accumulate more spare data could be irrational if a cheaper 10GB or 20GB plan meets your needs. You cannot assume a reward later will compensate for the higher bills now. Compare the actual cash difference first.

SMARTY's regular new-customer plans do not offer the same Piggybank mechanism. The old SMARTY Data Discount was a different arrangement under which qualifying legacy users received credit for unused data, and is discontinued for new customers. It cannot be presented as a current alternative to Sky rollover.

For a comparison of several rollover providers and their exact expiry rules, read our Best Data Rollover SIMs guide. This article's purpose is to decide between Sky and SMARTY, not to list every rollover network.

SMARTY Groups versus Sky sharing: which helps a multi-SIM household?

A household with two or more phones should compare the total household bill, not simply the price of a single SIM. SMARTY Groups and Sky Piggybank both connect more than one SIM, but they solve different problems.

SMARTY Mix & Match: a discount, not pooled data

SMARTY allows a Group owner to manage eligible SIMs together. Under Mix & Match, qualifying Group member plans can receive a 10% discount, subject to the precise plan and promotional exclusions. Group plans are distinct from a normal single-SIM checkout: adding two standard monthly products to a shopping basket is not enough to guarantee a Group discount.

For example, if an otherwise eligible £10 plan receives a 10% discount, the discounted charge would be £9 per renewal for that qualifying membership. Twelve such charges would save £12 relative to twelve undiscounted £10 charges, assuming the discount continues to apply. This is an illustration of how the discount works, not a claim that every £10 promotion is eligible or that the Group owner receives the same discount.

A SMARTY Group can contain two to eight SIMs. In Mix & Match, the Group owner manages payments, but different members can have different renewal dates, so the household charge may be collected on several dates. This matters for budgeting even when the total discounted charge looks attractive. The discount is for eligible Group arrangements, not a permanent promise that every advertised standalone promotion will stack. For a wider household comparison, see our family SIM-only guide.

SMARTY Everyone Unlimited: separate from Mix & Match

SMARTY also offers Everyone Unlimited, priced under its stated group structure rather than the Mix & Match 10% formula. SMARTY's published example lists £20 for the Group owner plus £15 for each additional member. Two unlimited SIMs under that structure cost £35 for the relevant monthly billing period in the example, compared with £40 for two independent £20 Unlimited SIMs before any other offer. Check the current Group purchase terms and individual eligibility before assuming these amounts.

Unlike Mix & Match, Everyone Unlimited uses one shared Group renewal date and one combined Group payment, with the owner paying. Do not apply an extra 10% on top of Everyone Unlimited unless the terms expressly allow it, and do not assume a promotional 100GB card stacks with Mix & Match. If someone joins Everyone Unlimited partway through the period, SMARTY says the owner pays the member's charge upfront and receives an adjustment for unused days as credit at the next renewal. This is useful for households whose members join on different dates.

Sky shared Piggybank: potentially useful, but not a bill discount

Sky's group advantage is primarily shared unused data across eligible SIMs on an account. If one family member regularly uses less than their allowance and another sometimes exceeds theirs, a shared bank may reduce the need for a paid top-up. It is not automatically a 10% reduction on the family's monthly payments.

Household decision: If you mainly want lower charges across several flexible SIMs, investigate SMARTY Group eligibility. If usage varies markedly and O2 works well, compare Sky's capped-data plans with the value of shared Piggybank data. Neither SMARTY's ordinary 40GB card nor a standard Sky card guarantees that a separate Group or multi-SIM arrangement has been activated.

Sky vs SMARTY coverage: O2 or Three at your postcode?

Sky uses O2's mobile network. SMARTY uses Three's network. That makes their most important technical difference local reception, not the number of 5G icons in a brochure. Even where a coverage map indicates service, a thick-walled flat, basement workplace or crowded railway station can behave differently.

Use Ofcom's free Map Your Mobile checker. Enter your home postcode, compare O2 and Three for indoor and outdoor 4G/5G, then check your workplace and regular routes. Where the two are close, a short-term SIM is useful for a real-world test before you sign for 24 months. Ofcom's broader performance estimate describes a postcode district, not a guaranteed personal speed.

What you findBetter next move
O2 reception is reliable indoors, but Three is weakShortlist a suitable Sky SIM; verify total contract cost.
Three is reliable where you use your phone, but O2 strugglesShortlist SMARTY, especially if a rolling plan matters.
Both work wellCompare your actual data usage, billing period, roaming and useful extras.
Both are weak at your main locationCheck an EE-network SIM or Vodafone-network SIM rather than forcing this pair.
The checker is inconclusive or you have an older handsetTest SIMs and verify that your phone supports each provider's calling features.

VodafoneThree network integration is being introduced in stages. SMARTY describes access to participating shared sites, but that does not mean full Vodafone coverage is already available to every SMARTY SIM. Sky continues to use O2; these two providers are not now on the same network. Judge the current service at your addresses, not a future integration plan.

Our Sky coverage guide explores O2 signal, device compatibility and 5G in greater depth. For general network technology rather than this buying decision, see MVNO coverage and speeds.

EU roaming: included data at SMARTY or a daily pass with Sky?

For someone who travels to eligible European destinations regularly, roaming can reverse a small difference in the UK headline price.

SMARTY: Eligible phone plans include EU roaming with a normal 12GB fair-use data cap for allowances above 12GB. The data comes out of the UK allowance rather than being an additional 12GB. If your monthly plan has only 5GB, you do not magically get 12GB abroad. The Republic of Ireland has a specific exception to the ordinary 12GB cap. A paid pass can expand access to eligible unused UK data on higher-allowance plans for a limited number of days; check current terms and whether the pass is relevant to your plan.

Sky: Roaming Passport Plus / Global Roaming Passport generally charges £2 per active 24-hour period in eligible countries when qualifying roaming use triggers the pass. The Republic of Ireland is treated differently, and qualifying Sky VIP Diamond customers can have the pass fee waived. Sky's fair-use guidance treats up to 25GB per billing period as reasonable Roaming Passport Plus data use; exceeding it can lead to restrictions or excess charges. Check the policy and account spend cap before a longer trip. UK Unlimited is not unlimited overseas data.

Consider a week-long visit with seven chargeable Sky roaming days: at the cited £2 pass price, that adds £14 to the trip's charges. Two similar trips could add £28 across a year. If SMARTY supplies enough included EU roaming data in your destinations, this extra cost can outweigh a modest domestic saving at Sky. If you seldom travel, Sky's roaming pass may have little effect on your choice.

The rule also works the other way: if you use more than SMARTY's ordinary EU allowance, eligible data add-ons or EU passes may be needed. SMARTY's roaming policy also warns that 60 consecutive days abroad can lead to suspension, following its notice process. SMARTY allows tethering abroad within the applicable limits, but it is not a blanket unlimited-roaming product. Check destination eligibility and non-EU charges before travel. International calls from the UK are not the same as roaming while abroad.

For the broader market and eligible destinations, read our best UK SIMs for EU roaming.

5G, eSIM, Wi-Fi Calling and tethering: the practical checks

Both brands offer 5G on supported devices, but availability depends on where you use the phone. Sky may require the free 5G Network add-on to be activated for an eligible handset; SMARTY's plans advertise 5G without a separate premium. Neither claim is a guarantee of indoor 5G speeds.

Both offer eSIM, although some older comparison tables still incorrectly say otherwise. Sky's eSIM activation depends on an eligible device and account setup. SMARTY advertises eSIM for standard phone plans and compatible devices; do not assume every old handset works with every digital SIM.

Wi-Fi Calling and 4G Calling/VoLTE matter when indoor reception is patchy. Ask the provider whether your exact handset model and software are supported. A phone that works with Wi-Fi Calling on another network may not automatically be supported on either new SIM.

Tethering is relevant if you use a laptop on trains or a tablet when away from Wi-Fi. A large UK allowance is not, by itself, a promise that every router or permanent home-broadband-replacement arrangement is covered by the plan's terms. Check fair-use and device policies, especially before choosing Unlimited. International roaming can have separate tethering, fair-use and device restrictions.

If eSIM activation or older-phone calling support is the deciding issue, our UK eSIM network guide and Wi-Fi Calling/VoLTE guide cover the wider technology questions. This comparison focuses on which provider and contract you should buy.

Price rises, cancellation and other costs people miss

A SIM with more data at a slightly lower advertised price may still be a worse purchase if the contract changes your options or the later bill is higher than expected.

Sky contract term and rises. The Sky 24-month cards in our catalogue show advertised base minimum costs. Some explicitly flag price changes; others say no price-rise information is stated. 'Not stated' is not a promise of a fixed price. For a new agreement, read the contractual payment schedule, any pre-disclosed in-contract increase, the start date and whether a promotional rate later expires. Under Ofcom's rules for new contracts from January 2025, specified price rises must be clearly expressed in pounds and pence before you agree, rather than tied to inflation percentages. If an increase is outside the agreed terms, different cancellation rights may apply.

SMARTY renewal and credit check. Its usual phone plans are prepaid, rolling monthly products with no long-term commitment or conventional pay-monthly credit check; Sky's cited 24-month and 30-day offers are subject to status and credit checks. SMARTY advertises no annual price rises in the same sense as multi-year pay-monthly agreements. That is not a perpetual promise that no future standalone plan price or promotional offer can change. Review the charge shown before each renewal, and check how and when to stop automatic renewal.

Early departure. An early Sky cancellation may entail a charge, even if Mix allows changes to your data allowance. SMARTY can usually be stopped before a new period renews, subject to the service terms; you do not automatically recover money for a month already paid for. Check the status of any Sky phone/device loan separately if you also bought a handset, because this comparison is about SIM-only service.

Extras. Check roaming passes, premium or international calls, extra data, spend-cap settings and any special Sky perks conditional on a TV subscription or a particular account. A marketing perk is valuable only when your account and tariff actually qualify.

The safest comparison is the provider's contract summary: monthly payments, minimum period, cancellation charges, price-rise schedule and what happens after the minimum term. Our SIM-only price rises guide explains the wider UK rules.

Who should choose Sky Mobile, and who should choose SMARTY?

You are buying for…Better starting pointReason to reject that starting point
A long-term home where O2 works better than ThreeSky MobileIf you cannot accept the term or later payment schedule.
A house move, gap year or uncertain work arrangementsSMARTY rolling or Sky rollingIf the other network is materially better where you live.
Regular 35–45GB use with seasonal spikesSky 50GBIf you would never use Piggybank or a 24-month obligation.
Consistently high use above 75GBSMARTY 100GBIf Three is poor locally or a different data policy is needed.
Two or more separately eligible SIMs with predictable useSMARTY GroupsIf the relevant promotion does not qualify for the Group discount.
Several SIMs sharing uneven data consumptionSky capped plansIf the bigger fixed-data allowances cost more than the saved top-ups are worth.
Several EU trips a yearSMARTYIf you need more than its included EU limit or travel outside eligible countries.
A month to test whether O2 works at homeSky 25GB 30-dayIf SMARTY on Three is already known to work and costs less.

Three scenarios where the obvious choice is wrong

'Sky has Piggybank, therefore it is always best for unused data.' Not when you pay for more gigabytes than you could ever consume. Reducing the monthly allowance can save more cash than accumulating unusable data or exchanging it for an uncertain reward.

'SMARTY is cheaper, therefore it is always best for a family.' Not if the advertised promotion is ineligible for Mix & Match, or if members are on a network with poor signal. A Group discount cannot repair coverage, and Everyone Unlimited has different maths.

'Sky means two years, so anyone who might move should ignore it.' Our selected Sky 25GB rolling offer demonstrates that this is false. You need to compare Sky's actual rolling and fixed-term cards. Equally, a Sky rolling price may be much higher than the fixed-term price, so flexibility should be valued explicitly.

How to switch between Sky and SMARTY without losing your number

  1. Check the current agreement. If leaving a Sky fixed-term plan, find the exact end date and ask for an early-termination quote where needed. You can text INFO to 85075 to request switching and contract information from your current UK mobile provider.
  2. Check network suitability. Compare O2 and Three with Ofcom's postcode checker, then test the weaker or less familiar signal where possible.
  3. Choose the exact plan. Review the data allowance, minimum term, introductory rates, EU roaming and handset/eSIM eligibility. For Sky, use the specific DealPriceCheck card and its tracked View Deal button.
  4. Request a PAC. Text PAC to 65075 from your current phone to keep your number. Give the PAC to your new provider. If you are leaving without keeping the number, the separate STAC process may be appropriate.
  5. Let the switch finish. Do not cancel the old mobile line manually before a PAC transfer if you want to keep that number. Check the first payment and switch confirmation afterwards.

For step-by-step transfer details, see how to keep your number when switching.

Frequently asked questions

Is Sky Mobile better than SMARTY?

Sky is a good candidate when O2 works better at your postcode or you can make useful use of Sky's eligible Piggybank and SIM terms. SMARTY is a good candidate when Three works and you value prepaid rolling plans, eligible Group savings or included EU roaming. The better purchase depends on the exact tariff and your expected length of stay.

Do Sky and SMARTY use the same network?

No. Sky uses O2, and SMARTY uses Three. They are separate buying options for coverage. Compare local O2 and Three signal before judging price or monthly gigabytes.

Is SMARTY a 30-day contract and Sky a 24-month contract?

SMARTY's standard SIMs are flexible rolling monthly plans. Many selected Sky SIMs have 24-month minimum terms, but Sky also offers rolling plans; our catalogue includes a 25GB 30-day Sky card. Check the term on each plan rather than attributing one contract length to the entire brand.

Does Sky roll over data while SMARTY does not?

Eligible capped Sky plans save spare data in Piggybank for up to 12 months, with whole-GB redemption rules. Regular new-customer SMARTY plans do not have the same data bank. SMARTY's old Data Discount arrangement has been discontinued for new customers and should not be confused with Sky rollover.

Is SMARTY Groups automatically 10% off every SIM?

No. Mix & Match has an eligible-member 10% discount with product and promotional restrictions. Everyone Unlimited is a different Group product, and an ordinary single-SIM checkout does not establish Group eligibility.

Which is better for roaming in Europe?

SMARTY typically includes eligible EU roaming with a data limit, normally up to 12GB out of your UK allowance on larger plans. Sky normally uses a paid Roaming Passport Plus 24-hour pass in eligible countries, with exceptions such as the Republic of Ireland and qualifying customer benefits. Count your travel days, destinations and expected data before choosing.

Can I get Sky Mobile or SMARTY on eSIM and 5G?

Both providers offer eSIM and 5G for compatible handsets and plans. Sky may require its free 5G Network add-on; settings and device eligibility matter. An older comparison page saying neither provider offers eSIM should not be treated as current evidence.

Is Sky's advertised minimum cost guaranteed for 24 months?

No. A catalogue's base total may not include a contractually specified later rise. Check the final Sky contract summary for all payments, timing of any changes and your exit rights. A card that says a rise is 'not stated' does not guarantee one cannot occur.

Does Sky or SMARTY require a credit check?

SMARTY advertises no credit check on its usual prepaid rolling phone SIMs. Sky says its mobile offers are subject to status and credit checks, including its 30-day offers. An eligibility check at checkout is not proof that approval or service is guaranteed.

Can I stop SMARTY after one month?

Its standard prepaid rolling products generally allow you to stop further renewals without a 12- or 24-month minimum term, provided you follow the cancellation and renewal process. That does not imply a refund of a period already paid for.

The verdict: compare a real Sky card with a real SMARTY card

If you want O2 service for the long term and would genuinely use the extra data or a Sky Piggybank balance, start with Sky Mobile's live SIM-only plans. For a mid-data example, Sky 50GB, 24 months is a useful specific starting point; review the whole payment schedule and the actual early-exit terms, not just its first monthly amount. If you want to test O2 without a two-year commitment, check the Sky 25GB rolling card instead.

If flexibility and Three reception matter more, compare SMARTY 40GB or SMARTY 100GB as appropriate to your usage. For households, evaluate the separate SMARTY Group arrangements against your actual monthly bills; do not assume any one-off promotional price and a Group discount stack.

Compare the right purchase: Sky 25GB, 24-month card · Sky 25GB, rolling card · Sky 50GB, 24-month card · SMARTY 20GB · SMARTY 40GB. Open Full plan details, then the appropriate View Deal button.

DealPriceCheck compares selected UK plans and may earn a commission from qualifying tracked purchases at no extra cost to you. Prices, offers and eligibility change. Verify the full payment schedule and contract summary for your exact selected deal before ordering.

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