How Many First Aiders Does My Business Need?

If you're asking "how many first aiders do I need", you're already ahead of most small business owners. Plenty of people assume one trained person and a green box is enough. Sometimes it is. But often it isn't, and the gap only becomes obvious when something goes wrong.

The honest answer is that the right number depends on your business. Your team size, the type of work you do, and the way your people are spread across sites and shifts all play a part. We help businesses across Cheshire and the North West work this out every week, and the answer is rarely as complicated as people fear.

This guide gives you everything you need to figure out your first aid requirements for businesses like yours. We'll walk through the regulations, the numbers, and the common traps, so you can get it right without overthinking it.

What the Law Actually Says

The Health and Safety (First-Aid) Regulations 1981 set out the legal framework. In plain terms, every employer in the UK must provide "adequate and appropriate" first aid cover for their workforce.

What counts as adequate and appropriate? That's where it gets interesting. The regulations deliberately avoid giving a single fixed number. Instead, they require you to carry out a first aid risk assessment and base your provision on the result.

Here's what the law does make clear.

• Every workplace must have at least one appointed person responsible for first aid arrangements
• Every workplace must have a stocked and maintained first aid kit
• The level of trained first aid cover must match the hazards and risks specific to your business
• First aid provision must account for all the times your business is operating, not just core hours

The HSE's guidance on first aid needs assessment fills in the detail. It provides recommended numbers based on risk level and headcount, and those recommendations are what most businesses, insurers, and enforcement officers use as the benchmark.

The key takeaway is that there is no single magic number in the legislation. But the HSE guidance gives you a very practical framework to follow.

It Depends on Three Things

When you're working out how many first aiders do I need, the answer comes down to three factors. Get these right and everything else falls into place.

How Many Employees You Have

This is the starting point. The more people you employ, the more first aid cover you need. That much is obvious. But the numbers might be lower than you expect for small teams.

• Fewer than 5 employees in a low-risk setting. You may only need an appointed person (someone responsible for calling emergency services and maintaining the first aid kit). A trained first aider is still recommended, but not strictly required.
• 5 to 25 employees in a low-risk setting. At least one person trained in Emergency First Aid at Work (EFAW).
• 25 to 50 employees in a low-risk setting. At least one person trained in First Aid at Work (FAW), plus an appointed person.
• More than 50 employees. One additional FAW first aider for every 100 workers in low-risk environments.

These are the baseline figures for low-risk workplaces. If your risk level is higher, the numbers go up significantly. We'll cover that in the table below.

What Kind of Work You Do (Risk Level)

Your first aid risk assessment must consider the hazards your team faces day to day. The HSE groups workplaces into three broad risk categories.

• Low risk includes offices, shops, libraries, and similar environments where the main hazards are slips, trips, and minor injuries
• Medium risk covers light manufacturing, warehousing, food processing, and assembly work
• High risk includes construction, chemicals, heavy machinery, large-scale manufacturing, and agricultural operations

The higher the risk, the more first aiders you need, and the higher level of qualification they require. A small office and a small building site might both have 20 employees, but their first aid requirements will be completely different.

Your Working Patterns (Shifts, Remote, Multi-Site)

This is the factor most businesses overlook. Your first aid provision must cover every shift and every site where your people work.

• If you run shift patterns, you need trained first aiders available on every shift, not just the day shift
• If you have remote or lone workers, you need a plan for how they access first aid when they're away from the main site
• If you operate across multiple locations, each location needs its own first aid cover based on its own headcount and risk level
• You also need to account for annual leave, sickness, and training days. If your only first aider is off, you have a gap in cover.

A business with 30 people working 9 to 5 in one office has a much simpler calculation than a business with 30 people split across three sites on rotating shifts. Both need to get the numbers right.

First Aider Numbers by Business Size and Risk

Here's a practical breakdown of the recommended first aider ratio to employees based on HSE guidance. Use this as your starting point, then adjust for your specific circumstances.

Low-risk workplaces (offices, shops, call centres)

• Fewer than 25 employees. At least 1 EFAW-trained first aider
• 25 to 50 employees. At least 1 FAW-trained first aider, plus an appointed person
• 50 to 100 employees. At least 1 FAW-trained first aider, plus 1 EFAW first aider
• More than 100 employees. 1 additional FAW first aider per 100 employees

Medium-risk workplaces (warehousing, light manufacturing, kitchens)

• Fewer than 20 employees. At least 1 EFAW or FAW-trained first aider, plus an appointed person
• 20 to 50 employees. At least 1 FAW-trained first aider for every 50 employees
• More than 50 employees. 1 additional FAW first aider per 50 employees

High-risk workplaces (construction, chemicals, heavy industry)

• Fewer than 5 employees. At least 1 EFAW-trained first aider, plus an appointed person
• 5 to 25 employees. At least 1 FAW-trained first aider
• More than 25 employees. 1 additional FAW first aider per 25 employees

These figures assume a single site with standard working hours. If your business runs shifts or spans multiple locations, you'll need to multiply accordingly.

Remember. These are the HSE's recommended minimums. Many businesses choose to train a few extra people as a buffer. It's a small investment compared to the cost of being caught short (less than one day's lost productivity).

EFAW vs FAW. Which Qualification Do Your First Aiders Need?

Understanding the difference between EFAW and FAW is essential when you're planning your first aid cover. They're not interchangeable.

Emergency First Aid at Work (EFAW)

• A one-day course covering the essentials
• Covers CPR, choking, bleeding, shock, and basic injury management
• Suitable for lower-risk workplaces with smaller teams
• Costs between £80 and £125 per person with us (less than one day’s lost productivity)
• Certificate valid for three years

First Aid at Work (FAW)

• A three-day course with broader and deeper content
• Covers everything in EFAW, plus fractures, burns, spinal injuries, medical emergencies (heart attacks, strokes, seizures, diabetic episodes), and more
• Required for higher-risk workplaces and larger teams
• Costs between £210 and £300 per person with us
• Certificate valid for three years

Here's a simple way to think about it.

• If your workplace is low risk and has fewer than 25 people, EFAW-trained first aiders will usually be enough
• If your workplace is low risk but has 25 or more people, you'll likely need at least one FAW-trained first aider
• If your workplace is medium or high risk, FAW is the standard regardless of team size

Whichever level your team needs, make sure you're tracking certificate expiry dates. A lapsed certificate means your first aider is no longer qualified, and your business is no longer compliant. We've written a full guide on what to do if your first aid certificate has expired.

Common Mistakes Businesses Make

After years of helping small businesses across Cheshire and the North West with their workplace first aid regulations UK obligations, we see the same mistakes come up again and again.

1. Only training one person. If your only first aider is off sick, on holiday, or leaves the company, you have zero cover. Always have at least one backup.
2. Forgetting about shifts. A first aider who works 9 to 5 doesn't help the team on the evening shift. Every shift needs its own cover.
3. Ignoring multi-site operations. First aid cover is per location, not per company. A first aider at head office doesn't count for the warehouse across town.
4. Letting certificates expire without noticing. Certificates last three years. Without a tracking system, they slip through the cracks. Set calendar reminders at six months and three months before expiry.
5. Assuming the first aid kit is enough. A stocked kit is a legal requirement, but it's not a substitute for trained people. The kit and the person go together.
6. Not doing a proper first aid risk assessment. Guessing the number isn't the same as assessing it. A documented needs assessment protects you if the HSE comes knocking.
7. Choosing EFAW when FAW is needed. EFAW is fine for many small, low-risk businesses. But if your workplace has genuine hazards, the shorter course won't give your first aiders the skills they need for serious incidents.

If any of these sound familiar, don't worry. They're all fixable, and usually more quickly and cheaply than people expect.

How to Work Out What You Need (Step by Step)

Ready to figure out exactly how many first aiders do I need? Follow these five steps.

1. Count your people. Include everyone who works at or visits your premises regularly. Part-time staff, contractors, and regular visitors all count.
2. Assess your risk level. Look at the hazards in your workplace and categorise yourself as low, medium, or high risk. If you're unsure, the HSE's guidance on first aid needs assessment has examples for different industries.
3. Map your working patterns. Write down every shift, every site, and every situation where people are working. Include remote workers and lone workers.
4. Use the numbers above. Match your headcount and risk level to the recommended figures in the table above. Then multiply for each shift and each site.
5. Add a buffer. Plan for at least one extra trained person per site to cover holidays, sickness, and staff turnover. This is the step that separates businesses that are technically compliant from businesses that are genuinely covered.

Once you've done this, you'll have a clear picture of how many first aiders you need and what level of training they require. Write it down as your first aid needs assessment and keep it with your other health and safety documents. The HSE expects this to be documented.

If you'd rather have someone do this with you, that's exactly what we're here for. You can chat with Penny, our compliance checker, to get a quick steer. Or get in touch with us directly and we'll walk through it together. There's no charge for the conversation.