Most people pay for far more mobile data than they use. Here's what each common allowance actually covers — and the cheapest way to get it on a UK SIM.
What uses mobile data?
- Video streaming: ~1GB/hour SD, 3GB+/hour HD, 7GB+/hour 4K
- Music/podcasts: ~100-150MB/hour
- Social media scrolling: ~150MB/hour
- Video calls: ~500MB-1.5GB/hour
- Maps/navigation: ~5-10MB/hour (barely anything)
- Web browsing/email: ~60MB/hour
How long does 500MB last?
500MB is enough for a month of light use — daily WhatsApp, occasional browsing and maps — but just 30 minutes of SD video would burn through it. It's the right size for a calls-and-texts phone or a backup SIM, not for a daily smartphone. Cheapest fit: a basic goodybag or Lebara plan around £5-£6.
Is 6GB enough?
For most people, yes — 6GB covers everyday social media, music streaming, maps and messaging with headroom. It's the sweet spot for light-to-average users who mostly use Wi-Fi at home and work. Around £6-£10/month on Giffgaff or Lebara.
What about 20GB-50GB?
20GB handles regular video streaming on commutes and hotspot use. 40-50GB is enough for heavy users — hours of daily video plus everything else — and typically costs £10-£15/month on rolling plans. If you regularly exceed 50GB, an unlimited data SIM is the smarter buy.
How to check what you actually use
- iPhone: Settings → Mobile Data — see total usage per app.
- Android: Settings → Network → Data usage — monthly totals and per-app breakdown.
- Your network's app: the most accurate figure for your billing period.
Do this before picking a plan — the UK average is around 8-12GB/month, but plenty of people pay for 50GB while using 5.
The cheapest plan for each usage level
- Under 2GB: a £5-£6 Lebara or Giffgaff plan covers it — see PAYG SIMs for occasional use.
- 5-10GB: the £6-£10 rolling-plan bracket — best value per GB.
- 20-50GB: £10-£15 plans — compare on SIM only deals.
- Unlimited: from around £20/month — unlimited data deals.
Pick the Right Plan Size
Free Giffgaff and Lebara SIMs — rolling plans for every data level from £5-£6/month, no contract.