CAT A vs CAT B Fit-Out: What’s the Difference and How Much Should You Be Paying?

If you’re taking on a new commercial lease, the terms CAT A and CAT B will likely come up in the agent’s particulars or the landlord’s specification.

Understanding the difference between CAT A and CAT B fit-out is absolutely essential before you sign, because it directly affects what you’re paying for, what you’re responsible for and how much budget you’ll need to get the space ready to work in.

Read on to learn to what each category covers, what they cost and a growing third option that sits between the two.

What a CAT A Fit-Out Covers

A CAT A fit-out brings a commercial space up to a basic, lettable standard. This is the landlord’s responsibility, and it covers the work that makes the building functional but not personalised. Think of it as a blank canvas.

A typical CAT A specification includes:

• Raised access flooring
• Suspended ceilings with basic lighting
• Mechanical and electrical services – heating, cooling, ventilation to a shell standard
• Fire detection and suppression systems
• Lift installations and common area finishes
• Basic toilet and welfare facilities

The space is clean, compliant, and ready to occupy in the most technical sense, but it doesn’t have any of the fit-out that makes it a working office. So, typically, no partitions, no workstations, no kitchen, no branding, and no personality.

In the South West and across much of England, CAT A fit-outs typically cost between £35 and £75 per square foot, depending on the building specification and the services being delivered.

What a CAT B Fit-Out Covers

A CAT B fit-out is where the space becomes the business. This is the tenant’s responsibility, turning the CAT A shell into a functioning workplace designed around how your business operates.

A Cat A vs Cat B fit out comparison comes down to this: CAT A gives you the building and shell; CAT B gives you the business environment. A typical CAT B scope includes:

• Space planning and interior design
• Partitioning, meeting rooms, and breakout areas
• Flooring, decoration, and finishes throughout
• Furniture, workstations, and storage
• IT and AV infrastructure – cabling, server rooms, screens
• Kitchen and refreshment facilities
• Branding, signage, and wayfinding
• Lighting upgrades beyond the CAT A provision

CAT B costs vary more widely because they depend on what you want the space to do. As a guide, CAT B fit-outs across the South West typically cost between £60 and £150+ per square foot.

A straightforward open-plan office fit-out sits at the lower end; a design-led headquarters with bespoke joinery, high-end finishes, and integrated AV will be towards the top.

CAT A+: The Middle Ground

CAT A+ is a relatively recent development, particularly common in city-centre office markets where landlords are competing for tenants. It’s sometimes called “plug and play” or “ready to occupy.”

A CAT A+ fit-out goes beyond the standard landlord specification to deliver a space that’s partially fitted out and ready for immediate occupation. That might include partitioned meeting rooms, a fitted kitchen, basic furniture, and finished flooring – enough for a business to move in without commissioning a full CAT B project.

It’s an attractive option for:

• Smaller businesses that don’t want the cost or complexity of a full fit-out
• Companies on shorter leases where the payback period on a CAT B project is tight
• Businesses that need to occupy quickly and can’t wait for a design-and-build programme

The cost is typically shared between landlord and tenant or built into the rent. It’s worth understanding exactly what’s included and what isn’t, because “CAT A+” isn’t a standardised specification – it varies from landlord to landlord.

What You Should Know Before Signing a Lease

The category of fit-out affects your budget, your timeline and your obligations. A few questions worth asking before you commit:

• Is the space being delivered as CAT A, CAT A+, or shell and core? The answer determines your starting point and your fit-out budget
• Is a landlord contribution available? Many landlords offer a fit-out contribution or rent-free period to help with CAT B costs, but you need to negotiate this before signing
• What reinstatement obligations does the lease include? Some leases require you to strip the space back to CAT A condition when you leave, which is an additional cost worth factoring in
• What’s the dilapidations position? Understanding your end-of-lease obligations upfront avoids expensive surprises later

Information You Should Have Before You Sign

The difference between CAT A and CAT B fit outs is straightforward once you’ve seen them laid out. The part that catches people is the cost – and the gap between what the landlord delivers and what the business needs to operate.

If you’re looking at new premises and want to understand what the fit-out will involve, get in touch. We work with businesses and landlords across the South West and beyond and we’re happy to walk through the numbers before you commit to anything.