In this Tech Insight, we look at how UK businesses can identify, block, and protect themselves against the growing nuisance (and threat) of spam calls, and why doing so is now essential for productivity, security, and reputation.
More Than a Nuisance
If you’ve noticed more spam calls slipping through lately, you’re not imagining things. Nuisance calls, i.e. from robotic sales pitches to full-blown scam attempts, have become a major source of disruption (and risk) for UK businesses.
In fact, research from Ofcom estimates that UK consumers and businesses receive over 4.4 billion nuisance calls and texts per year, with a significant proportion targeting workplaces. From lost productivity and operational distraction to fraud and reputational damage, spam calls are creating headaches across sectors. For some, they’re also creating serious financial losses.
What Counts As a Spam Call?
Broadly speaking, spam calls refer to any unsolicited or unwanted phone call, particularly those made in bulk. They may originate from real people or bots, domestic numbers or international spoofed lines, and their intentions can range from sales to scams. Common categories include:
– Telemarketing calls. These are usually from legitimate businesses, yet are often annoying and unwanted.
– Robocalls. This type of call uses pre-recorded messages, often tied to fake tech support, medical cover or financial offers.
– Scam calls. These calls are designed to try and trick the recipient into handing over personal or financial information.
– Silent or abandoned calls. These are often used to verify if a number is “live” for future targeting.
Although some spam calls are relatively harmless, many are sophisticated fraud attempts. The UK’s National Cyber Security Centre (NCSC) notes an increasing link between spam calls and cybercrime, including phishing, identity theft, and voice cloning scams.
A Growing Threat to Businesses
Spam calls are no longer just a nuisance to receptionists or front-line teams. For UK companies of all sizes, they can lead to missed leads, disrupted workflows, and even data breaches.
For example, a recent study by Truecaller found that globally, businesses lose an average of $14 billion a year to phone scams. While exact UK figures are harder to isolate, UK Finance reported over £1.2 billion in fraud losses in 2023, with social engineering scams, often initiated via phone, accounting for a large slice.
For example:
– A logistics company in Manchester reported receiving over 20 spoofed calls a day, some impersonating HMRC or customs officers.
– A legal firm in Surrey was conned out of £28,000 after a senior partner unknowingly responded to a voice-phishing scam, believing it was a client confirming bank details.
– An SME in the retail sector said they had to dedicate an admin staff member solely to filtering phone calls, costing them hours of productivity weekly.
As fraud tactics become more advanced, including the use of AI-generated voices and deepfake impersonation, spam calls are quickly evolving from an irritation into a significant security risk.
How Are They Getting Your Number?
One of the most frustrating aspects of spam calls is how widespread and persistent they are, even for numbers that were never shared publicly.
Here’s how they’re likely getting in:
– Data breaches. Your number may have been compromised in a company breach or exposed via a third-party contact.
– Web scraping. Spammers use bots to harvest numbers from websites, contact pages, and social media profiles.
– Number generators. Robocallers simply dial every possible variation of UK numbers using auto-dialling software.
– Data brokers. Some marketing companies sell on contact lists without appropriate consent.
Even legitimate-seeming calls may not be what they appear. Number spoofing allows fraudsters to display fake caller IDs, often mimicking well-known institutions or even internal office numbers.
Why Businesses Need a Serious Defence Strategy
The problem is no longer solvable simply with caller ID alone and, for UK businesses, relying on staff to manually screen calls is unsustainable. Not only does it eat into valuable time, but it also increases the risk of missing genuine client calls.
Instead, a layered and proactive approach is needed. Ideally, this type of approach should include:
– Network-level blocking. All major UK mobile networks (including EE, O2, Vodafone and Three) now offer spam filtering and scam call protection. Some, like O2’s Call Defence, automatically warn users about suspicious numbers. EE flags suspected scam calls in real time.
– Smartphone features. Both Android and iPhone users can activate built-in call blocking and spam detection tools. On Android, turning on ‘Caller ID & spam’ and filtering spam calls will silence known nuisance numbers. On iPhone, enabling ‘Silence Unknown Callers’ sends calls from unknown numbers straight to voicemail – though with the risk of missing new contacts.
– Call screening software. Businesses can deploy dedicated VoIP services or call management apps like Hiya, Truecaller for Business, or BT’s Call Protect to detect, divert and report malicious calls. These platforms often use real-time databases of spam numbers and AI-based filtering to block unwanted calls before they reach a human.
– Staff awareness and call protocols. Employee training is essential. Staff should be reminded never to give sensitive information over the phone unless they can verify the caller. Set up internal rules, such as always calling back a client on a verified number instead of trusting inbound requests.
– Registration with TPS (Telephone Preference Service). UK businesses can also register with the Corporate Telephone Preference Service (CTPS) to legally opt out of receiving marketing calls. While this doesn’t block international spam, it offers some protection from UK-based telemarketers, and gives businesses legal grounds to complain if calls persist.
Common Spam Call Tactics in 2025
Spam calls have evolved. It’s no longer just robotic PPI chasers. Today’s fraudsters are deploying more advanced (and sinister) tricks. For example, watch out for:
– Impersonation scams. Callers claiming to be from HMRC, the bank, Microsoft, or your own IT provider.
– “Can you hear me?” traps. Designed to get a voice recording of you saying “yes”, which can be used to authorise charges or access.
– Fake client inquiries. Scammers pretending to be new customers, asking for personal or operational details.
– Missed call scams. You receive a one-ring call from an international number and calling back triggers premium charges.
There are also increasing reports of AI voice synthesis being used to impersonate real people, including senior managers. These so-called “deep voice” scams are alarmingly convincing and often target finance or HR departments.
Tools and Tech to Help Businesses Fight Back
Fortunately, there are real, actionable tools businesses can use to block, track, and report spam calls. Just some examples of such tools include:
– PhoneSystem (BT, 3CX, RingCentral, etc.). Business-grade phone systems often include spam detection, call screening, and custom call-routing features.
– Spam call reporting portals. Use the ICO’s nuisance call reporting tool and Action Fraud to report malicious activity. This helps build national data for enforcement.
– AI-based call blockers. Tools like Nomorobo, RoboKiller, and Truecaller Premium now cater to UK businesses and use dynamic databases to identify threats in real time.
It’s also worth keeping an eye on Ofcom’s anti-scam call initiatives, including new proposals to limit international number spoofing and force providers to apply stricter blocking at the network level. Telecoms companies must also now verify caller ID information, with penalties for failure to comply.
What Does This Mean For Your Business?
While individuals have long had the option to silence unknown numbers or install spam blockers, the stakes for businesses are far higher. For example, one missed call might be a scam, whereas another could be a potential client. That’s the balancing act UK firms are now having to perform daily, all while trying to protect staff, safeguard data, and maintain trust with customers. Also, today’s spam calls are often weaponised to breach security systems, manipulate staff, or undermine day-to-day operations.
However, many small and medium-sized enterprises still treat spam call management as a back-office issue. But the evidence suggests it deserves boardroom-level attention. Whether it’s the £1.2 billion in fraud losses reported last year, or the growing number of AI-enabled voice scams, the message is that this is a frontline threat. If left unmanaged, it risks eroding not just productivity, but confidence, both internally and externally.
At the same time, thankfully, telecom providers and regulators like Ofcom are starting to take more decisive steps, from enforcing stricter ID verification rules to proposing new crackdowns on number spoofing. These efforts, while welcome, still rely heavily on businesses taking initiative, by adopting smarter tools, reviewing internal call-handling protocols, and registering with services like the CTPS.
What this all means for UK businesses is a shift in mindset where phone security can no longer really be treated separately from cybersecurity. Stakeholders across departments, from IT and operations to HR and finance, should now collaborate to manage the risks, spot the red flags, and ensure no call gets through that shouldn’t. It’s not just about stopping nuisance calls. It’s about protecting reputation, maintaining customer confidence, and staying one step ahead.
