Start with a realistic data budget

Every family holiday has its own rhythm, but one thing is universal: data disappears faster than you expect. Between maps, messages, and keeping the kids entertained, a week in Europe can easily chew through 10GB or more. Before you compare plans, work out what your family actually needs.

Here are some typical data uses to help you estimate:

• Maps and navigation: Around 5MB per hour if you use live traffic, or next to nothing if you download offline maps in advance.
• Messaging: WhatsApp text messages barely touch your allowance, but sharing photos and videos adds up quickly — a single minute of video call can use 5-10MB.
• Streaming: A 30-minute episode on standard definition uses about 300MB, while high definition can hit 3GB. Multiply that by a few episodes for each child.
• Social media: Scrolling through feeds with autoplay videos can easily consume 1GB in an hour.

For a family of four, with two children watching videos on the journey, you might need 10-15GB for a week if you rely solely on mobile data. But most hotels, cafes, and airports offer free Wi-Fi. Use that for heavy downloads and streaming. As a rule of thumb, aim for at least 5GB per person for a week, or 20GB shared if you plan to tether.

Shared plans versus individual SIMs

Once you know your likely usage, decide how to structure it. A shared plan puts all your data in one pot, which is often cheaper per gigabyte and easier to manage. Many UK networks let you add family members to your account for a small monthly fee, and some allow you to set individual limits so one person cannot hog the whole allowance. This is ideal if you want to keep an eye on total spend.

Individual SIMs give each person their own allowance, which can be simpler for older teenagers who want independence. It also means if one SIM runs out, the others keep working. The downside is more admin — you will need to top up or monitor several accounts. For younger children, a separate SIM with a strict cap is a good safety net. Some networks offer eSIMs for tablets and smartwatches, which can be added to a shared plan without a physical card.

Consider a hybrid: a shared plan for parents and younger children, and a small individual SIM for a teenager. That balances control with flexibility.

Roaming rules and fair use policies

Since the UK left the EU, roaming rules have changed. Some UK networks still include EU roaming at no extra cost, but many now charge a daily fee or require a roaming pass. Check your plan's fair use policy — typically you can use 20-30GB per month in the EU before surcharges apply. If you exceed that, you may be charged per gigabyte.

Also check what is included for calls and texts. Many plans include calls to UK numbers while roaming, but calling local numbers or other countries can be expensive. For international calling, consider using a VoIP app over data, or buy a local SIM for longer stays. Be aware that Switzerland, Turkey, and some islands are not in the EU roaming zone, so you will need a separate add-on or local SIM.

Hotspot rules and tethering

If you plan to use one phone as a hotspot for tablets or your children's devices, check your provider's tethering rules. Some networks allow it freely, some count it as normal data, and others block it entirely or charge extra. Read the small print before you travel — the last thing you want is a surprise bill.

Tethering also drains battery quickly and can be slow when multiple devices connect. A better option for a family is a portable MiFi or a local SIM in a tablet. If you do tether, set a data cap on the host phone and turn it off when not needed. Some networks offer a dedicated hotspot device with its own plan, which can be simpler.

Child-friendly controls and safety

Before you go, set up parental controls on every device. Most networks offer content filters and spending caps that you can manage from an app. You can also set individual data limits so children cannot run up charges. Teach them to switch to Wi-Fi for streaming, and to ask before downloading large apps or games.

For younger children, consider a separate SIM with a small allowance and no international calling. For older children, agree on rules: no answering unknown numbers, no sharing location publicly. If they need to call home, using a messaging app over data is often cheapest, but that requires data — so ensure their plan has enough. Alternatively, a voice add-on for international calls might be worth it.

Practical ways to stretch your data

Even with a generous plan, data can vanish. These habits help:

• Download offline: Maps, music, podcasts, and videos before you leave.
• Turn off auto-play: On social media and streaming apps.
• Use Wi-Fi for heavy tasks: Updates, backups, and streaming.
• Set data warnings: On every device, at 80% and 100% of your allowance.
• Use low-data messaging: Text-only messages instead of video calls.

For trips longer than a week, a local SIM often works out cheaper than roaming. For shorter breaks, a UK plan with EU roaming is usually fine. Whichever you choose, check the details before you fly — and enjoy your holiday without worrying about the bill.