Most small and medium businesses in Greater Manchester rely on email for everything from invoicing to new business enquiries, and most assume the spam filter built into their email platform is keeping them safe. It isn't, not on its own. Spam filters are designed to catch obvious junk: dodgy pharmaceutical adverts, lottery scams, mass-sent rubbish. They were never built to catch a well-researched email that looks like it came from your managing director asking finance to pay an invoice today. That's the email that actually costs businesses money, and it sails straight past basic filtering because it doesn't look like spam at all.
Why basic filtering falls short
Modern phishing emails are targeted. Attackers research a company on LinkedIn, work out who the finance manager is, spoof a supplier's email address, and send a message that reads exactly like a normal business request. There's no suspicious language, no obvious spelling mistakes, and often no attachment or link for the filter to flag. The email simply asks someone to update a bank account, approve a payment, or log into a "portal" that looks identical to the real thing. A spam filter has nothing to catch, because nothing about the email looks like spam. It looks like business as usual, which is exactly the point.
The domain authentication layer: SPF, DKIM and DMARC
One of the most common tricks is sending an email that appears to come from your own domain, or from a trusted supplier's domain, when it hasn't actually been sent by them. Three technical records fix this:
- SPF lists which mail servers are allowed to send email on behalf of your domain.
- DKIM adds a digital signature to outgoing mail so receiving servers can confirm it hasn't been tampered with.
- DMARC tells other mail servers what to do with messages that fail SPF or DKIM checks, and sends you reports when someone tries to impersonate your domain.
Set up together, these three records make it far harder for criminals to send convincing fake emails pretending to be from your business, and they stop a lot of spoofed emails pretending to be from your suppliers from reaching your inbox in the first place. A surprising number of SME domains in the UK still have none of these configured correctly, which leaves the door wide open.
Protecting the click
Even with domain authentication in place, a phishing email can still arrive from a genuinely compromised supplier account, which is where link protection matters. Modern email security tools rewrite links so that when someone clicks, the destination is checked in real time against known malicious sites, not just checked once when the email first arrived. This matters because attackers often set up a link that looks harmless at the point of delivery and only turns malicious hours later, once it's already sitting in someone's inbox. Attachment scanning that opens files in an isolated environment before they reach the user adds a further layer, catching malware hidden in documents that look completely ordinary.
Giving staff a way to report
Technology catches most things, but not everything, which is why your team needs a fast, simple way to flag anything that looks suspicious. A one-click "report phishing" button in Outlook or your email client removes the friction of forwarding a message to IT and waiting, and it builds a habit of reporting rather than ignoring or, worse, clicking. It also feeds useful intelligence back to whoever manages your email security, so patterns of attack against your business can be spotted and blocked earlier. Pair this with short, regular staff awareness sessions, not a once-a-year tick-box exercise, and your people become an active layer of defence rather than the weakest link.
Building the layers that matter
No single control stops every phishing attempt, which is exactly why layering matters. Domain authentication stops spoofing, link and attachment protection catches malicious content, and staff reporting catches what slips through both. Together, these layers reduce risk far more effectively than any spam filter working alone, and they're achievable for a business of any size with the right support behind them.
If your email security currently begins and ends with a spam filter, it's worth finding out where the gaps actually are. Valetech Solutions works with SMEs across Greater Manchester to set up DMARC, DKIM and SPF correctly, add link and attachment protection, and give staff a straightforward way to report suspicious emails. Get in touch with Valetech Solutions to talk through your current setup.