Best 21-day eSIM Plans for United Kingdom
Going to United Kingdom for 21 days (3 weeks)? These plans cover your full trip — all with instant QR delivery, no contract, and no SIM card to pick up at the airport.
Starting from (Free)
$2.34
Pro membership — save 7%
$2.18
Premium membership — save 12%
$2.06
Recommended 21-day plans — United Kingdom
Best Value
Uki Mobile
999 GB
30 days validity
$72.50
$0.07/GB
All 12 plans covering 21+ days
Uki Mobile
999 GB
30 days validity
$72.50
$0.07/GB
Uki Mobile+
50 GB
30 days validity
$54.00
$1.08/GB
Uki Mobile
20 GB
30 days validity
$32.00
$1.60/GB
Uki Mobile+
20 GB
30 days validity
$38.50
$1.93/GB
Uki Mobile
10 GB
30 days validity
$19.50
$1.95/GB
Uki Mobile+
10 GB
30 days validity
$23.50
$2.35/GB
Uki Mobile
5 GB
30 days validity
$13.00
$2.60/GB
Uki Mobile
3 GB
30 days validity
$9.00
$3.00/GB
Uki Mobile+
5 GB
30 days validity
$15.50
$3.10/GB
EUconnect
3 GB
30 days validity
$9.50
$3.17/GB
Oceanlink
3 GB
30 days validity
$10.50
$3.50/GB
Discover
200 MB
30 days validity
$2.34
$11.98/GB
Other trip lengths for United Kingdom
21-day eSIM plans by destination
Frequently asked questions — 21-day United Kingdom eSIM
What eSIM do I need for 21 days in United Kingdom?
Look for a plan with at least 21 days of validity. The plans above all cover your full trip. Activate when you land — validity starts from first use, not from purchase.
How much data do I need for 21 days in United Kingdom?
A typical traveler uses 1–2 GB per day for maps, messaging, and occasional video. For 21 days that is roughly 21–42 GB.
When should I install my United Kingdom eSIM?
Install before you travel, at home over Wi-Fi. Activation begins when you arrive and connect to a local carrier.
Can I top up if I run out of data?
Many plans are rechargeable. You can purchase an additional plan from LTE.app at any time — no need to find a SIM card shop.
Save on every trip with Pro or Premium
Pro 7% off · Premium 12% off · Smart Coach AI · Offline activation
United Kingdom travel connectivity
All United Kingdom pages — linked for faster research
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📡Coverage
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