Moving house comes with a long list of things to check: survey, fixtures, parking, school run. Broadband and mobile signal often sit near the bottom, and they are exactly the things that will irritate you daily if you get them wrong. A dead spot in the back bedroom or a connection that crawls at 8pm is hard to fix and impossible to renegotiate once you have the keys. An hour of checking now saves months of frustration.

Start With the Postcode, Not the Sales Brochure

Every listing mentions "fibre broadband" as though it means something precise. It rarely does. Begin with the official checkers rather than the agent's summary: Ofcom's coverage checker covers mobile and broadband for a postcode, and each of the main mobile networks runs its own map. For broadband, ThinkBroadband and the individual providers' postcode tools will show which technologies reach the address and roughly what speeds they expect.

Use two or three sources. They draw on different data and disagree more often than you would think, particularly at the edge of a rollout area. Check the postcode rather than the street name, too: coverage can change from one side of a road to the other, and new-build plots are sometimes registered under a different postcode entirely.

How to Read a Coverage Map Properly

Coverage maps are predictions, not measurements. They are modelled from mast locations, terrain and reported data, and they usually describe outdoor coverage. A patch of deep colour means a strong signal is expected outside. It says nothing about whether that signal survives two stone walls and a set of triple-glazed windows.

Watch the wording. Most maps separate "likely" indoor coverage from "limited" or outdoor-only. Treat outdoor-only as meaning you cannot rely on calls indoors without Wi-Fi calling, which itself depends on decent broadband.

What Weakens the Signal Indoors

Old stone walls, thick brick, metal-framed windows, foil-backed insulation, basements and hillside positions all eat into mobile coverage. Trees in leaf can knock it back in summer. If the property is rural, hilly or built before the twentieth century, assume the map is optimistic and test in person.

Check What Broadband Is Actually Available

"Fibre" in the UK covers everything from full fibre to the premises, where a fibre cable reaches your wall, to fibre to the cabinet, where the last stretch is copper and speeds fall with distance from the cabinet. Many urban and new-build properties are also served by alternative networks such as CityFibre, Hyperoptic or Gigaclear, either alongside Openreach or instead of it.

• The fastest connection available, and which network provides it.
• Whether full fibre, cable or only part-copper broadband is on offer.
• Typical peak-time speeds, not just headline maximums.
• Whether the address is already connected or needs a new line.
• Any nearby rollout plans - useful to know, but never sign based on one.

Look out for the difference between "available" and "connected". Available means an order can be placed, sometimes with a long lead time or a contribution towards connection costs.

Test the Property in Person

Visit with your own phone on your own network, ideally twice: once on a weekday evening, when neighbours are streaming, and once at the weekend. Peak-hour performance is the number that matters. A speed test at 11am on a Tuesday flatters almost everything.

Walk the whole property rather than standing in the hallway. Try the main bedroom, the room you would use as an office, the kitchen and the garden. Make a call, send a photo, run a speed test, try a video call. Bars on the screen are a rough guide at best. If you want real numbers, iPhone users can open Field Test mode by dialling *3001#12345#*, and most Android phones show signal strength under Settings, About Phone, SIM status. Readings closer to -70 dBm are strong; past -110 dBm, expect trouble.

If the sellers or tenants are still living there, ask what broadband they have and, where possible, run a test on their connection.

Questions Worth Asking Before You Sign

Estate agents are not broadband surveyors and may not know the answers. Ask anyway, and put anything important in writing.

1. Which broadband provider is connected, and what speeds do they get?
2. Is there an active phone line, and who supplies it?
3. Is full fibre available now, or only part-copper broadband?
4. Do the current occupants get mobile signal indoors, and on which network?
5. Are there any known dead spots?
6. For flats: is there a building-wide arrangement, and who manages it?
7. Are there restrictions on installing a dish, aerial or external cabling?
8. Is the property listed, in a conservation area, or leasehold with installation rules?
9. How long would a new connection take to install?

Practical Catches That Trip People Up

New builds are frequently missing from coverage databases or listed under a plot number, so a check can show nothing when the street is fully served. A call to the developer or a nearby postcode usually clears it up.

Flats, listed buildings and conservation areas complicate installation. Where cabling crosses land owned by someone else, a wayleave may be required, and in leasehold blocks the freeholder or managing agent usually has to approve works. Rules vary, so check with your conveyancer or the local authority before assuming you can mount a dish or drill through a wall.

One more: if your current provider does not cover the new address, you may be able to leave your contract early, but exit charges can apply. Read the terms before you exchange, not after.

Do This Before You Exchange

Run an Ofcom postcode check, then a provider check for at least two networks. Look at the coverage map for the network you actually use. Visit the property at a busy time with your phone, test every room that matters and note the results. Ask the questions above and keep the answers.

If the signal or speed looks marginal, tell your conveyancer and factor it into the deal. Some landlords will agree to a broadband installation, and some vendors will negotiate when a buyer can demonstrate the address is poorly served. Ten minutes of checking at the offer stage beats a year of dropped calls in the spare room. For anything involving leases, listed buildings or wayleaves, take proper legal advice before you commit.

Photo: William Hadley / Pexels