Nuisance calls are a daily annoyance, but without Caller ID it's difficult to know who's on the end of the line until you answer it - then it's too late and you're stuck talking. Happily, Ofcom has banned companies from withholding their number while making cold calls. See also: How to block a number on an iPhone and How to block a number on Android.

In January BT also announced a free service - BT Call Protect - that will help its customers avoid nuisance calls. It claims its new service will enable it to divert to a junk voicemail box up to 30 million nuisance calls a week.

BT aims to achieve this through the analysis of huge amounts of live data at its centre in Oswestry in Shropshire to identify rogue numbers - typically those that make enormous numbers of calls - and to add them to a blacklist.

Numbers will also be added to this blacklist when many customers report nuisance calls from the same number, and you can compile your own blacklists which can include individual numbers, withheld numbers and international calls. To add a number simply call 1572 after receiving the unwanted call. This works only after you have signed up for Call Protect, of course.

The great news is that it's now available and it's free if you're a BT customer. All you need to do to enable the service on your line is to click through to www.bt.com/callprotect or call 0800 389 1572. You will have to go through an ordering process, but you'll need only your BT phone number and postcode to do so: no payment details are required and it is a permanently free service, not a special offer which becomes a paid service after, say, 12 months.

Stop nuisance calls with BT Call Protect

Telephone Preference Service - register with TPS by text

Despite over 17 million domestic phone numbers being registered with the TPS, the government scheme seems to have done little to reduce the number of nuisance calls in my experience. Telemarketing firms are supposed to check this database and avoid calling those numbers.

You can register your number on the TPS but it's only one step to banish all nuisance calls. Many companies either ignore the rules, or call from outside the UK, meaning the rules don't apply.

As of May 2016 it is now a lot easier to register your mobile phone number on the TPS, since you can now do so by text message. Simply type TPS followed by your email address to 78070 to register on the official Do Not Call database.

Get Caller ID

As long as you have a compatible phone, you can ask your telephone provider if it's possible to display the number of the person calling. BT currently charges £1.75 per month for Caller Display so you can see the number of the person calling, but it's included for free if you pay for your line rental for 12 months up front. Virgin charges £2.25, but TalkTalk and Sky both offer it for free.

If the number calling is in your phone's address book then the name appears instead. On the BT handset I was using until recently, international calls were flagged up as exactly that, and since we don't have any overseas relations (or friends who would call), it's easy to avoid answering calls from anyone we don't know.

Actively block calls

The main issue with nuisance calls is that even if you know not to answer them, it's still a pain that you have to listen to the phone ringing at all, or get up and walk to it to find out who's calling.

It may be possible that your telephone provider will block specific numbers but it will typically cost money, usually a few pounds per month. BT calls this Choose to Refuse, but it also has other 'calling features' which include blocking all withheld UK numbers.

That's where call blockers come in. These are boxes which you plug in-line with your existing landline. I tried one from Amazon - the CPR 1200 - which costs £40. That might sound expensive, but if nuisance calls really bother you it could be well worth it for the peace and quiet.

How to block nuisance calls

The box comes with 200 known nuisance numbers already programmed, but you can add a new number simply by pressing the button on top after you answer a call and discover it's a nuisance or cold caller. (This works only if the number calling is visible via Caller ID, and you need Caller ID for the box to work at all.)

How to block nuisance calls

The CPR 1200 also lets you block international calls, withheld or private numbers, and entire area codes. Everything is done using your phone's keypad, and it comes with a quick-reference sticker so you don't have to memorise which combinations to press. Since the box is powered from the phone line, it doesn't need a mains adaptor so is convenient and easy to install.

It can even handle two phone lines and two phone handsets.

BT BT8500 Advanced Call Blocker

An alternative to a separate box is a new phone which has similar features built in. BT's BT8500 Advanced Call Blocker costs £79.99.

How to block nuisance calls

The main handset includes buttons for controlling the built-in answerphone, and synchs its address book with other handsets (there are twin, triple and quad handset packs). When someone calls, the BT8500 answers it and asks the person to state their name. Only then will it ring and alert you. You'll then hear a message telling you who's calling and you can choose whether to accept the call only once, always, send it to answerphone or always block it.

Friends and family will automatically get through as long as their number is in your address book. That's the only slight frustration with the BT8500, as it's laborious to enter lots of names and numbers via the numberpad. There's no way to import an address book from an existing phone (or smartphone). However, if you're lazy, you can just wait until people call and add their numbers that way.

Like the CPR 1200, it also lets you block calls by type so you can tell it to block all international and withheld numbers, and all numbers with a certain area code. It goes a bit further by letting you also block all mobile numbers and payphones, apart from those in your address book of course.

Another nice feature of the BT8500 is Do Not Disturb, which mutes the ringer and LEDs. You can tag certain people as VIPs in the address book, so their calls still get through.