Unlimited data SIM-only deals

Every unlimited-data SIM we track, cheapest first. They all run on one of the UK’s three networks, so pick the coverage you want and pay the least for it.
42 deals, cheapest first
Lycamobile
Lycamobile
Uses EE masts
24-month contract
Unlimited 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
£9.00/mo
for the first 6 months
  • Then £18.00 a month after that
  • £378.00 total over 24 months
  • Average over 24 months: £15.75 a month
  • £0 upfront · no cashback required
Get this deal from Lycamobile*
Sky Mobile
Sky Mobile
Uses O2 masts
12-month contract
Unlimited 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
£21.00/mo
every month of the contract
  • £252.00 total over 12 months
  • £0 upfront · no cashback required
Get this deal from Sky Mobile
Ecotalk
Ecotalk
Uses EE masts
monthly rolling
Unlimited 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
£22.00/mo
cancel or change any time
  • £0 upfront · no contract tying you to future price changes
Get this deal from Ecotalk*
Lycamobile
Lycamobile
Uses EE masts
12-month contract
Unlimited 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
£11.00/mo
for the first 3 months
  • Then £22.00 a month after that
  • £231.00 total over 12 months
  • Average over 12 months: £19.25 a month
  • £0 upfront · no cashback required
Get this deal from Lycamobile*
O2
O2
Uses O2 network
24-month contract
Unlimited Data5G
Unlimited minutes & texts
EU roaming includedeSIM availableWi-Fi calling included
£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 O2
Lebara
Lebara
Uses VodafoneThree masts
12-month contract
Unlimited 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 £22.50 a month from the start
  • −Unused data does not roll over to the next month
£11.25/mo
for the first 3 months with code LEBARA3M
  • Then £22.50 a month after that
  • £236.25 total over 12 months
  • Average over 12 months: £19.69 a month
  • £0 upfront · no cashback required
Get this deal from Lebara*
Your Co-op Mobile
Your Co-op Mobile
Uses EE masts
monthly rolling
Unlimited Data5G
Unlimited minutes & texts
No price risesEU roaming includedeSIM availableWi-Fi calling included
Important to know
  • −Unused data does not roll over to the next month
  • −The link opens Your Co-op Mobile's full plans page — choose the Unlimited plan there
£24.00/mo
cancel or change any time
  • £0 upfront · no contract tying you to future price changes
Get this deal from Your Co-op Mobile*
Lycamobile
Lycamobile
Uses EE masts
monthly rolling
Unlimited 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
£12.00/mo
for the first month
  • Then £24.00 a month after that
  • Monthly rolling — cancel or change any time
  • Average over your first 12 months: £23.00 a month
  • £0 upfront · no contract tying you to future price changes
Get this deal from Lycamobile*
Honest Mobile
Honest Mobile
Uses VodafoneThree masts
monthly rolling
Unlimited Data5G
Unlimited minutes & texts
No price riseseSIM availableWi-Fi calling included
Important to know
  • ⚠EU roaming is free only for the first 5 days of each trip; the cache does not state costs beyond that.
  • −Unused data does not roll over to the next month
£25.00/mo
cancel or change any time
  • £0 upfront · no contract tying you to future price changes
Get this deal from Honest Mobile
Lebara
Lebara
Uses VodafoneThree masts
monthly rolling
Unlimited 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 £25.00 a month from the start
  • −Unused data does not roll over to the next month
£12.50/mo
for the first 3 months with code LEBARA3M
  • Then £25.00 a month after that
  • Monthly rolling — cancel or change any time
  • Average over your first 12 months: £21.88 a month
  • £0 upfront · no contract tying you to future price changes
Get this deal from Lebara*
EE
EE
Uses EE network
24-month contract
Unlimited 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
£26.00/mo
until 28 February 2027
  • Then £28.50 a month from 1 March 2027 until 28 February 2028
  • Then £31.00 a month from 1 March 2028
  • £679.00 total over 24 months
  • Average over 24 months: £28.29 a month
  • £0 upfront · no cashback required
Get this deal from EE
Vodafone
Vodafone
Uses Vodafone network
24-month contract
Unlimited Data5G
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…
£26.00/mo
until 31 March 2027
  • Then £28.50 a month from 1 April 2027 until 31 March 2028
  • Then £31.00 a month from 1 April 2028
  • £674.00 total over 24 months
  • Average over 24 months: £28.08 a month
  • £0 upfront · no cashback required
Get this deal from Vodafone*
EE
EE
Uses EE network
24-month contract
Unlimited Data5G
Perk includedeSIM 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
£33.00/mo
until 28 February 2027
  • Then £35.50 a month from 1 March 2027 until 28 February 2028
  • Then £38.00 a month from 1 March 2028
  • £847.00 total over 24 months
  • Average over 24 months: £35.29 a month
  • £0 upfront · no cashback required
Get this deal from EE
EE
EE
Uses EE network
24-month contract
Unlimited Data5G
Perk includedeSIM availableWi-Fi calling includedPerks worth up to £18.99
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
£33.00/mo
until 28 February 2027
  • Then £35.50 a month from 1 March 2027 until 28 February 2028
  • Then £38.00 a month from 1 March 2028
  • £847.00 total over 24 months
  • Average over 24 months: £35.29 a month
  • £0 upfront · no cashback required
Get this deal from EE
VOXI
VOXI
Uses VodafoneThree masts
monthly rolling
Unlimited 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
  • −The link opens VOXI's full plans page — choose the Unlimited plan there
£35.00/mo
cancel or change any time
  • £0 upfront · no contract tying you to future price changes
Get this deal from VOXI*
EE
EE
Uses EE network
monthly rolling
Unlimited 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
£35.00/mo
cancel or change any time
  • £0 upfront · no contract tying you to future price changes
Get this deal from EE
ParentShield
ParentShield
Uses EE masts
monthly rolling
Unlimited 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
£39.99/mo
cancel or change any time
  • £0 upfront · no contract tying you to future price changes
Get this deal from ParentShield
Vodafone
Vodafone
Uses Vodafone network
monthly rolling
Unlimited 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…
£40.00/mo
cancel or change any time
  • £0 upfront · no contract tying you to future price changes
Get this deal from Vodafone*
EE
EE
Uses EE network
24-month contract
Unlimited Data5G
Perk includedeSIM availableWi-Fi calling includedPerks worth up to £25.99
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
£43.00/mo
until 28 February 2027
  • Then £45.50 a month from 1 March 2027 until 28 February 2028
  • Then £48.00 a month from 1 March 2028
  • £1087.00 total over 24 months
  • Average over 24 months: £45.29 a month
  • £0 upfront · no cashback required
Get this deal from EE
EE
EE
Uses EE network
24-month contract
Unlimited Data5G
Perk includedeSIM availableWi-Fi calling includedPerks worth up to £25.99
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
£43.00/mo
until 28 February 2027
  • Then £45.50 a month from 1 March 2027 until 28 February 2028
  • Then £48.00 a month from 1 March 2028
  • £1087.00 total over 24 months
  • Average over 24 months: £45.29 a month
  • £0 upfront · no cashback required
Get this deal from EE
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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.