20GB SIM-only deals

Plenty of data for most people — SIMs from 20GB up to 100GB, cheapest first.
110 deals, cheapest first
Vodafone
Vodafone
Uses Vodafone network
12-month contract
35GB Data5G
Unlimited minutes & texts
eSIM availableWi-Fi calling included
Important to know
  • ⚠EU roaming: Zone A roaming is included on all pay monthly plans, but wider European roaming needs a Plus or Premier plan…
£8.00/mo
until 31 March 2027
  • Then £10.50 a month from 1 April 2027
  • £106.00 total over 12 months
  • Average over 12 months: £8.83 a month
  • £0 upfront · no cashback required
Get this deal from buymobiles*
Lycamobile
Lycamobile
Uses EE masts
12-month contract
40GB Data5G
Unlimited minutes & texts
No price riseseSIM availableWi-Fi calling included100 international mins
Important to know
  • ⚠EU roaming is included at no extra cost in most bundles, but not on every plan.
  • −Unused data does not roll over to the next month
£4.00/mo
for the first month
  • Then £8.00 a month after that
  • £92.00 total over 12 months
  • Average over 12 months: £7.67 a month
  • £0 upfront · no cashback required
Get this deal from Lycamobile*
Lycamobile
Lycamobile
Uses EE masts
24-month contract
50GB Data5G
Unlimited minutes & texts
No price riseseSIM availableWi-Fi calling included100 international mins
Important to know
  • ⚠EU roaming is included at no extra cost in most bundles, but not on every plan.
  • −Unused data does not roll over to the next month
£4.00/mo
for the first 3 months
  • Then £8.00 a month after that
  • £180.00 total over 24 months
  • Average over 24 months: £7.50 a month
  • £0 upfront · no cashback required
Get this deal from Lycamobile*
Vodafone
Vodafone
Uses Vodafone network
12-month contract
60GB Data5G
Unlimited minutes & texts
eSIM availableWi-Fi calling included
Important to know
  • ⚠EU roaming: Zone A roaming is included on all pay monthly plans, but wider European roaming needs a Plus or Premier plan…
£9.00/mo
until 31 March 2027
  • Then £11.50 a month from 1 April 2027
  • £118.00 total over 12 months
  • Average over 12 months: £9.83 a month
  • £0 upfront · no cashback required
Get this deal from buymobiles*
Lebara
Lebara
Uses VodafoneThree masts
12-month contract
30GB Data5G
Voucher dealNo price risesEU roaming includedeSIM available
Important to know
  • ⚠You must enter the code LEBARA10 at Lebara's checkout to get the intro price — without it you pay £9.00 a month from the start
  • −Unused data does not roll over to the next month
£2.49/mo
for the first 3 months with code LEBARA10
  • Then £9.00 a month after that
  • £88.47 total over 12 months
  • Average over 12 months: £7.37 a month
  • £0 upfront · no cashback required
Get this deal from Lebara*
Vodafone
Vodafone
Uses Vodafone network
12-month contract
70GB Data5G
Unlimited minutes & texts
eSIM availableWi-Fi calling included
Important to know
  • ⚠EU roaming: Zone A roaming is included on all pay monthly plans, but wider European roaming needs a Plus or Premier plan…
£10.00/mo
until 31 March 2027
  • Then £12.50 a month from 1 April 2027
  • £130.00 total over 12 months
  • Average over 12 months: £10.83 a month
  • £0 upfront · no cashback required
Get this deal from buymobiles*
Lycamobile
Lycamobile
Uses EE masts
monthly rolling
30GB Data5G
Unlimited minutes & texts
eSIM availableWi-Fi calling included100 international mins
Important to know
  • ⚠EU roaming is included at no extra cost in most bundles, but not on every plan.
  • −Unused data does not roll over to the next month
£5.00/mo
for the first month
  • Then £10.00 a month after that
  • Monthly rolling — cancel or change any time
  • Average over your first 12 months: £9.58 a month
  • £0 upfront · no contract tying you to future price changes
Get this deal from Lycamobile*
NOW Mobile
NOW Mobile
Uses EE masts
monthly rolling
20GB Data5G
Unlimited minutes & texts
No price risesWi-Fi calling included
Important to know
  • ⚠EU roaming: Some plans come with free EU roaming, but it is not stated as included on all plans.
  • −Unused data does not roll over to the next month
£10.00/mo
cancel or change any time
  • £0 upfront · no contract tying you to future price changes
Get this deal from NOW Mobile
VOXI
VOXI
Uses VodafoneThree masts
monthly rolling
60GB Data5G
Unlimited minutes & texts
Endless social media dataNo price riseseSIM availableWi-Fi calling included
Important to know
  • ⚠EU roaming is not included — you need to buy a European Roaming Pass first (priced at checkout).
  • −Unused data does not roll over to the next month
  • −The link opens VOXI's full plans page — choose the 60GB plan there
£10.00/mo
cancel or change any time
  • £0 upfront · no contract tying you to future price changes
Get this deal from VOXI*
Vodafone
Vodafone
Uses Vodafone network
24-month contract
60GB Data5G
Unlimited minutes & texts
eSIM availableWi-Fi calling included
Important to know
  • ⚠EU roaming: Zone A roaming is included on all pay monthly plans, but wider European roaming needs a Plus or Premier plan…
£11.00/mo
until 31 March 2027
  • Then £13.50 a month from 1 April 2027 until 31 March 2028
  • Then £16.00 a month from 1 April 2028
  • £314.00 total over 24 months
  • £40.00 cashback via buymobiles
  • Average after cashback: £11.42 a month
  • £0 upfront
Get this deal from buymobiles*
VOXI
VOXI
Uses VodafoneThree masts
monthly rolling
75GB Data5G
Unlimited minutes & texts
No price riseseSIM availableWi-Fi calling included
Important to know
  • ⚠EU roaming is not included — you need to buy a European Roaming Pass first (priced at checkout).
  • −Unused data does not roll over to the next month
£12.00/mo
cancel or change any time
  • £0 upfront · no contract tying you to future price changes
Get this deal from buymobiles*
Lycamobile
Lycamobile
Uses EE masts
12-month contract
90GB Data5G
Unlimited minutes & texts
No price riseseSIM availableWi-Fi calling included100 international mins
Important to know
  • ⚠EU roaming is included at no extra cost in most bundles, but not on every plan.
  • −Unused data does not roll over to the next month
£6.00/mo
for the first 3 months
  • Then £12.00 a month after that
  • £126.00 total over 12 months
  • Average over 12 months: £10.50 a month
  • £0 upfront · no cashback required
Get this deal from Lycamobile*
VOXI
VOXI
Uses VodafoneThree masts
monthly rolling
25GB Data5G
Unlimited minutes & texts
Endless social & music dataNo price riseseSIM availableWi-Fi calling included
Important to know
  • ⚠EU roaming is not included — you need to buy a European Roaming Pass first (priced at checkout).
  • −Unused data does not roll over to the next month
  • −The link opens VOXI's full plans page — choose the 25GB plan there
£12.00/mo
cancel or change any time
  • £0 upfront · no contract tying you to future price changes
Get this deal from VOXI*
Lebara
Lebara
Uses VodafoneThree masts
12-month contract
50GB Data5G
Voucher dealNo price risesEU roaming includedeSIM available
Important to know
  • ⚠You must enter the code LEBARA3M at Lebara's checkout to get the intro price — without it you pay £13.50 a month from the start
  • −Unused data does not roll over to the next month
£6.75/mo
for the first 3 months with code LEBARA3M
  • Then £13.50 a month after that
  • £141.75 total over 12 months
  • Average over 12 months: £11.81 a month
  • £0 upfront · no cashback required
Get this deal from Lebara*
Ecotalk
Ecotalk
Uses EE masts
monthly rolling
30GB Data5G
Unlimited minutes & texts
No price riseseSIM availableWi-Fi calling included
Important to know
  • ⚠EU roaming: £2 per day
  • −Unused data does not roll over to the next month
£14.00/mo
cancel or change any time
  • £0 upfront · no contract tying you to future price changes
Get this deal from Ecotalk*
EE
EE
Uses EE network
24-month contract
20GB Data5G
eSIM availableWi-Fi calling included
Important to know
  • ⚠EU roaming: A daily charge applies to use allowances in the EU/EEA on standard plans, while Essentials Plus, All Rounder…
  • −Unused data does not roll over to the next month
£15.00/mo
until 28 February 2027
  • Then £17.50 a month from 1 March 2027 until 28 February 2028
  • Then £20.00 a month from 1 March 2028
  • £415.00 total over 24 months
  • Average over 24 months: £17.29 a month
  • £0 upfront · no cashback required
Get this deal from EE
Lycamobile
Lycamobile
Uses EE masts
monthly rolling
75GB Data5G
Unlimited minutes & texts
eSIM availableWi-Fi calling included100 international mins
Important to know
  • ⚠EU roaming is included at no extra cost in most bundles, but not on every plan.
  • −Unused data does not roll over to the next month
£7.50/mo
for the first month
  • Then £15.00 a month after that
  • Monthly rolling — cancel or change any time
  • Average over your first 12 months: £14.38 a month
  • £0 upfront · no contract tying you to future price changes
Get this deal from Lycamobile*
Lycamobile
Lycamobile
Uses EE masts
monthly rolling
50GB Data5G
Unlimited minutes & texts
No price riseseSIM availableWi-Fi calling included100 international mins
Important to know
  • ⚠EU roaming is included at no extra cost in most bundles, but not on every plan.
  • −Unused data does not roll over to the next month
£7.50/mo
for the first month
  • Then £15.00 a month after that
  • Monthly rolling — cancel or change any time
  • Average over your first 12 months: £14.38 a month
  • £0 upfront · no contract tying you to future price changes
Get this deal from Lycamobile*
NOW Mobile
NOW Mobile
Uses EE masts
monthly rolling
50GB Data5G
Unlimited minutes & texts
No price risesWi-Fi calling included
Important to know
  • ⚠EU roaming: Some plans come with free EU roaming, but it is not stated as included on all plans.
  • −Unused data does not roll over to the next month
£15.00/mo
cancel or change any time
  • £0 upfront · no contract tying you to future price changes
Get this deal from NOW Mobile
Vodafone
Vodafone
Uses Vodafone network
monthly rolling
25GB Data5G
Unlimited minutes & texts
eSIM availableWi-Fi calling included
Important to know
  • ⚠EU roaming: Zone A roaming is included on all pay monthly plans, but wider European roaming needs a Plus or Premier plan…
£15.00/mo
cancel or change any time
  • £0 upfront · no contract tying you to future price changes
75GB for first 3 months
Get this deal from Vodafone*
EE
EE
Uses EE network
12-month contract
50GB Data5G
eSIM availableWi-Fi calling included
Important to know
  • ⚠EU roaming: A daily charge applies to use allowances in the EU/EEA on standard plans, while Essentials Plus, All Rounder…
  • −Unused data does not roll over to the next month
£18.00/mo
until 28 February 2027
  • Then £20.50 a month from 1 March 2027
  • £228.50 total over 12 months
  • Average over 12 months: £19.04 a month
  • £0 upfront · no cashback required
Get this deal from EE
Sky Mobile
Sky Mobile
Uses O2 masts
12-month contract
40GB Data5G
Unlimited minutes & texts
eSIM availableWi-Fi calling included
Important to know
  • ⚠Roaming Passport Plus costs £2 a day in 120 destinations; only the Republic of Ireland is free.
  • ⚠Sky Mobile raises prices each year during the contract
£18.00/mo
every month of the contract
  • £216.00 total over 12 months
  • £0 upfront · no cashback required
Get this deal from Sky Mobile
EE
EE
Uses EE network
24-month contract
25GB Data5G
eSIM availableWi-Fi calling included
Important to know
  • ⚠EU roaming: A daily charge applies to use allowances in the EU/EEA on standard plans, while Essentials Plus, All Rounder…
  • −Unused data does not roll over to the next month
£19.00/mo
until 28 February 2027
  • Then £21.50 a month from 1 March 2027 until 28 February 2028
  • Then £24.00 a month from 1 March 2028
  • £511.00 total over 24 months
  • Average over 24 months: £21.29 a month
  • £0 upfront · no cashback required
Get this deal from EE
Sky Mobile
Sky Mobile
Uses O2 masts
12-month contract
50GB Data5G
Unlimited minutes & texts
eSIM availableWi-Fi calling included
Important to know
  • ⚠Roaming Passport Plus costs £2 a day in 120 destinations; only the Republic of Ireland is free.
  • ⚠Sky Mobile raises prices each year during the contract
£20.00/mo
every month of the contract
  • £240.00 total over 12 months
  • £0 upfront · no cashback required
Get this deal from Sky Mobile
Vodafone
Vodafone
Uses Vodafone network
monthly rolling
50GB Data5G
Unlimited minutes & texts
eSIM availableWi-Fi calling included
Important to know
  • ⚠EU roaming: Zone A roaming is included on all pay monthly plans, but wider European roaming needs a Plus or Premier plan…
£20.00/mo
cancel or change any time
  • £0 upfront · no contract tying you to future price changes
150GB for first 3 months
Get this deal from Vodafone*
ParentShield
ParentShield
Uses EE masts
monthly rolling
50GB Data
Unlimited minutes & texts
No price rises
Important to know
  • ⚠EU roaming is not included — EU roaming works on Roam Stage plans but is pay-per-use (zone charges), not inclusive.
  • −Unused data does not roll over to the next month
£20.99/mo
cancel or change any time
  • £0 upfront · no contract tying you to future price changes
Get this deal from ParentShield
EE
EE
Uses EE network
monthly rolling
25GB Data5G
eSIM availableWi-Fi calling included
Important to know
  • ⚠EU roaming: A daily charge applies to use allowances in the EU/EEA on standard plans, while Essentials Plus, All Rounder…
  • −Unused data does not roll over to the next month
£30.00/mo
cancel or change any time
  • £0 upfront · no contract tying you to future price changes
Get this deal from EE
Show 25 more deals — each beaten on price or data by one above
Vodafone
Vodafone
Uses Vodafone network
12-month contract
30GB Data5G
Unlimited minutes & texts
eSIM availableWi-Fi calling included
Important to know
  • ⚠EU roaming: Zone A roaming is included on all pay monthly plans, but wider European roaming needs a Plus or Premier plan…
£10.00/mo
until 31 March 2027
  • Then £12.50 a month from 1 April 2027
  • £130.00 total over 12 months
  • Average over 12 months: £10.83 a month
  • £0 upfront · no cashback required
Get this deal from buymobiles*
VOXI
VOXI
Uses VodafoneThree masts
monthly rolling
20GB Data5G
Unlimited minutes & texts
No price riseseSIM availableWi-Fi calling included
Important to know
  • ⚠EU roaming is not included — you need to buy a European Roaming Pass first (priced at checkout).
  • −Unused data does not roll over to the next month
£10.00/mo
cancel or change any time
  • £0 upfront · no contract tying you to future price changes
Get this deal from buymobiles*
VOXI
VOXI
Uses VodafoneThree masts
monthly rolling
35GB Data5G
Unlimited minutes & texts
No price riseseSIM availableWi-Fi calling included
Important to know
  • ⚠EU roaming is not included — you need to buy a European Roaming Pass first (priced at checkout).
  • −Unused data does not roll over to the next month
£15.00/mo
cancel or change any time
  • £0 upfront · no contract tying you to future price changes
Get this deal from buymobiles*
NOW Mobile
NOW Mobile
Uses EE masts
monthly rolling
30GB Data5G
Unlimited minutes & texts
No price risesWi-Fi calling included
Important to know
  • ⚠EU roaming: Some plans come with free EU roaming, but it is not stated as included on all plans.
  • −Unused data does not roll over to the next month
£15.00/mo
cancel or change any time
  • £0 upfront · no contract tying you to future price changes
Get this deal from NOW Mobile
NOW Mobile
NOW Mobile
Uses EE masts
monthly rolling
80GB Data5G
Unlimited minutes & texts
No price risesWi-Fi calling included
Important to know
  • ⚠EU roaming: Some plans come with free EU roaming, but it is not stated as included on all plans.
  • −Unused data does not roll over to the next month
£20.00/mo
cancel or change any time
  • £0 upfront · no contract tying you to future price changes
Get this deal from NOW Mobile
O2
O2
Uses O2 network
24-month contract
20GB Data5G
Unlimited minutes & texts
EU roaming includedeSIM availableWi-Fi calling included
£21.00/mo
until 31 March 2027
  • Then £23.50 a month from 1 April 2027 until 31 March 2028
  • Then £26.00 a month from 1 April 2028
  • £554.00 total over 24 months
  • Average over 24 months: £23.08 a month
  • £0 upfront · no cashback required
Get this deal from O2
Vodafone
Vodafone
Uses Vodafone network
24-month contract
50GB Data5G
Unlimited minutes & texts
eSIM availableWi-Fi calling included
Important to know
  • ⚠EU roaming: Zone A roaming is included on all pay monthly plans, but wider European roaming needs a Plus or Premier plan…
£21.00/mo
until 31 March 2027
  • Then £23.50 a month from 1 April 2027 until 31 March 2028
  • Then £26.00 a month from 1 April 2028
  • £554.00 total over 24 months
  • Average over 24 months: £23.08 a month
  • £0 upfront · no cashback required
Get this deal from Vodafone*
Vodafone
Vodafone
Uses Vodafone network
24-month contract
30GB Data5G
Unlimited minutes & texts
eSIM availableWi-Fi calling included
Important to know
  • ⚠EU roaming: Zone A roaming is included on all pay monthly plans, but wider European roaming needs a Plus or Premier plan…
£22.00/mo
until 31 March 2027
  • Then £24.50 a month from 1 April 2027 until 31 March 2028
  • Then £27.00 a month from 1 April 2028
  • £578.00 total over 24 months
  • Average over 24 months: £24.08 a month
  • £0 upfront · no cashback required
Get this deal from Vodafone*
O2
O2
Uses O2 network
24-month contract
50GB Data5G
Unlimited minutes & texts
EU roaming includedeSIM availableWi-Fi calling included
£24.00/mo
until 31 March 2027
  • Then £26.50 a month from 1 April 2027 until 31 March 2028
  • Then £29.00 a month from 1 April 2028
  • £626.00 total over 24 months
  • Average over 24 months: £26.08 a month
  • £0 upfront · no cashback required
Get this deal from O2
Vodafone
Vodafone
Uses Vodafone network
monthly rolling
30GB Data5G
Unlimited minutes & texts
eSIM availableWi-Fi calling included
Important to know
  • ⚠EU roaming: Zone A roaming is included on all pay monthly plans, but wider European roaming needs a Plus or Premier plan…
£33.00/mo
cancel or change any time
  • £0 upfront · no contract tying you to future price changes
Get this deal from Vodafone*
Vodafone
Vodafone
Uses Vodafone network
monthly rolling
80GB Data5G
Unlimited minutes & texts
eSIM availableWi-Fi calling included
Important to know
  • ⚠EU roaming: Zone A roaming is included on all pay monthly plans, but wider European roaming needs a Plus or Premier plan…
£35.00/mo
cancel or change any time
  • £0 upfront · no contract tying you to future price changes
Get this deal from Vodafone*
Sky Mobile
Sky Mobile
Uses O2 masts
12-month contract
75GB Data5G
Unlimited minutes & texts
eSIM availableWi-Fi calling included
Important to know
  • ⚠Roaming Passport Plus costs £2 a day in 120 destinations; only the Republic of Ireland is free.
  • ⚠Sky Mobile raises prices each year during the contract
£108.00/mo
every month of the contract
  • £1296.00 total over 12 months
  • £0 upfront · no cashback required
Get this deal from Sky Mobile
Want to pay from your bank? See the rolling SIMs you can pay by Direct Debit →

Monthly prices are each provider’s current cost, checked against their site — last updated 8 August 2026. Links marked * earn us a commission if you buy — it never changes what you pay, and it plays no part in how we rank deals.