Email security best practices for UK small businesses

21 May, 2026

Email security best practices are no longer a nice to have for UK small businesses. Most successful cyber attacks still begin with a single email, and it only takes one mistake to cause real disruption.

Why email security matters for small businesses

For many owners in places like Brighton, Crawley or Eastbourne, email is the main way you speak to customers and suppliers. That also makes it a prime target for criminals.

If an attacker gets into a mailbox they can:

Send fake invoices that look genuine
Reset passwords for other systems
Steal sensitive information about staff and clients
Use your domain to send spam or phishing to others

The good news is that clear email security best practices can reduce this risk without making everyday work painful.

Recognising phishing and scam emails

Phishing is when someone sends an email that looks real but is designed to trick you into clicking a link, opening an attachment, or sharing information.

Common warning signs include:

Pressure and urgency such as “pay this today or we will close your account”
Spelling mistakes or odd wording in what should be a professional message
Sender addresses that are nearly right but not exact
Unexpected attachments, especially ZIP or Office files asking you to enable content
Links that do not match the visible text when you hover over them

Make it normal for staff to slow down and check before they click. A short pause is cheaper than a data breach.

For a deeper look at phishing and how it works you can read our guide What every small business should know about phishing.

Core email security best practices for your business

You do not need to be technical to put sensible controls in place. Focus on a few key areas and keep improving over time.

Use strong passwords and multi factor authentication

Every mailbox should have:

A unique, long password that is not reused on other sites
Multi factor authentication such as a phone prompt or code

This makes it much harder for criminals to log in even if a password leaks in a data breach.

Keep software and devices up to date

Attackers often use old software flaws to get in. Make sure:

Windows and macOS updates are installed regularly
Email apps such as Outlook are kept current
Phones and tablets used for work email are updated too

If you are unsure why updates matter, this article explains more about keeping Windows current for business use: Why update Windows if it is not broken.

Turn on modern spam and malware filtering

Most cloud email systems such as Microsoft 365 and Google Workspace include built in filtering. Ask whoever manages your IT to:

Enable advanced spam and phishing protection
Block known dangerous file types
Quarantine suspicious messages for review

These filters will not catch everything, but they remove a large number of bad emails before staff ever see them.

Control who can send as your domain

Technical records such as SPF, DKIM and DMARC tell receiving mail servers which systems are allowed to send email on behalf of your domain.

Configured correctly they help:

Reduce spoofed emails that pretend to be from your business
Improve the chances of your genuine emails reaching inboxes

Your IT provider or email host can set these up. It is a one off job that supports your wider email security best practices.

Training your team to handle email safely

Technology helps, but people still make the final decision to click or not. A simple training plan can make a big difference.

Keep guidance short and practical

Avoid long policy documents that nobody reads. Instead, share clear rules such as:

Never send passwords or bank details by email
Always double check changes to payment details by phone using a known number
Ask a colleague or manager if an email feels odd

Refresh this guidance every few months and whenever you see a new type of scam targeting your sector.

Run simple awareness exercises

You can run light touch exercises without blaming anyone. For example:

Share screenshots of real phishing attempts your business has received
Ask staff to point out the warning signs
Discuss what they would do if they clicked by mistake

This helps people feel confident about speaking up early rather than hiding an error.

Protecting sensitive information in email

Not every message is equal. Payment details, contracts, staff records and customer data all need extra care.

Consider these steps:

Use secure links rather than attachments for very sensitive files
Limit who can see shared mailboxes that handle finance or HR queries
Set up automatic rules to add disclaimers where needed
Back up your email data so you can recover quickly after an incident

If you are unsure about backup options, this guide explains the basics in plain language: How to back up my business data.

What to do if someone clicks on a bad email

Even with good email security best practices in place, mistakes will happen. The aim is to limit the damage.

If you think someone has clicked on a malicious link or opened a risky attachment:

Ask them to tell you or your IT contact immediately
Change their email and key system passwords straight away
Sign them out of all sessions if your system allows it
Run a full antivirus and anti malware scan on the device
Warn colleagues and, if needed, key customers that an account may have been misused

For serious incidents or suspected data loss, the National Cyber Security Centre has clear guidance for UK organisations on handling cyber incidents. You can find it on the NCSC small business guide.

Building email security into everyday work

Email security is not a one off project. It is a set of habits and controls that you review regularly.

A simple checklist to revisit every quarter might include:

Are all staff using multi factor authentication
Have any new starters or leavers been handled correctly in the email system
Are devices up to date and protected
Have we seen any new phishing patterns
Do we need a short refresher session for the team

How My Tech Team can help

If you would like help reviewing your email security best practices or setting up safer systems for your business in Brighton, Crawley or nearby areas, support is available.

You can book a short, no obligation chat to talk through your current setup and your concerns. Together we can look at practical steps that fit your size and budget.

Schedule a 30 minute call to get started.