Planning Office Fit-Out Costs for a City of London Office: A Requirements-Led Budget Guide

Start with the budget question the project must answer

The City of London office fit-out budget should answer what your workplace must deliver, not merely multiply floor area by a headline rate. Office fit-outs are usually priced per square foot of floor area, but the useful figure depends on the starting condition, specification, inclusions and project assumptions.

Treat the fit-out brief and budget as connected. The brief establishes requirements; the budget provides the financial framework; changing one can affect the other. Adding meeting rooms, increasing workstation numbers, specifying higher finishes or introducing bespoke joinery can change the investment required. A fixed budget may therefore require you to prioritise, adjust or approach some requirements differently.

Published figures show why a single City of London answer would mislead. A 2026 UK guide gives a Cat B fit-out budget of £65 to £130 per square foot, depending on specification, while a separate guide gives £60 to £90 per square foot for a basic Cat B fit-out and £90 to £130 per square foot for a mid-range Cat B fit-out. The £60 to £90 figure is approximately £650 to £970 per square metre, and the £90 to £130 figure is approximately £970 to £1,400 per square metre; both are source-specific planning figures, not a City of London quotation.

The cited guide also reports that global fit-out costs rose by 2% to 6% over the preceding year. That evidence supports rechecking a planning allowance, not applying an automatic uplift to your project. Start by defining the workplace, then select a benchmark whose scope resembles it.

Separate the fit-out from the wider office decision

The office fit-out budget should separate construction and building services from the other costs required to make the office usable. Rent, deposits, moving costs, ongoing management and other occupation costs belong in the wider office decision. List them separately rather than assuming that a published fit-out rate includes them.

A Cat A starting condition commonly covers base infrastructure. One guide says Cat A works often include flooring, ceilings, lighting, heating, cooling, ventilation, power distribution, fire systems and basic decoration, with a guide price of around £30 to £70 per square foot. Another source describes Cat A as infrastructure such as water, power, toilets, showers and fire detection, plus a blank canvas for a Cat A+ or Cat B fit-out, with a cited average range of £50 to £100 per square foot. These are different source-specific ranges, so record which definition you are using.

Cat B takes the space towards an operational workplace. A cited description includes furnishings, meeting pods, meeting spaces, breakout rooms, and kitchen and dining areas, with a typical range of £60 to £120 per square foot. Another guide gives around £70 to £140 per square foot for a mid-range Cat B fit-out and £140 to £250 per square foot for a more bespoke workplace with high-quality finishes, integrated technology or custom joinery.

Keep these cost lines visible in your schedule:

• construction, finishes and building services;
• furniture and workstation supply;
• IT, structured data, AV and workplace technology;
• design, surveying, cost consultancy and project management fees;
• contingency and risk allowances;
• rent, moving, occupation and ongoing management costs.

Cost guides may focus on construction or include furniture, professional fees, AV equipment and other operational items. Read the inclusions before comparing totals.

Choose the starting condition before applying a rate

The premises starting condition determines whether your project is a refresh, a Cat A-to-Cat B delivery or something more extensive. Classify that condition before applying a per-square-foot allowance.

A refresh of an existing office may need limited alterations, replacement finishes or changes to the layout. One 2026 UK guide places a basic refresh of an existing office nearer £40 to £65 per square foot. That figure describes a basic refresh, not a universal City of London rate.

A cost-conscious Cat B fit-out might achieve £80 to £100 per square foot, while a high-specification environment could exceed £200 per square foot. The same source says furniture typically adds £30 to £80 per square foot. Keep the furniture allowance separate unless the benchmark explicitly includes it.

Taking Cat A space and delivering a full Cat B fit-out for a quality London office typically requires £120 to £200 or more per square foot. This is a London planning benchmark for that specific starting condition and quality level, not a promise about a City of London building.

A separate UK guide gives a typical office fit-out range of £35 to £180 or more per square foot, depending on the property’s baseline condition, required specification and mechanical and electrical infrastructure complexity. The breadth of that range is useful: it shows why a rate chosen before a survey and scope definition can give false precision.

For your first budget pass, record whether the premises are an existing fitted office, Cat A, Cat A+ or another condition, then state what the landlord provides and what your project must supply.

Build the area and capacity model

The workplace capacity model should begin with attendance and work patterns rather than a simple desk total. Include current headcount, realistic future growth, remote-working patterns and shared-workstation assumptions in the brief. Headcount can affect desks, meeting rooms, circulation, storage, kitchen facilities, breakout areas, power, data, lighting, furniture and total space.

Use this sequence:

1. Record current employees by team and role.
2. Add a realistic growth assumption and the period it is intended to cover.
3. Describe attendance patterns: permanent presence, regular hybrid attendance, occasional visits and remote-only work.
4. State whether employees need permanent workstations, shared desks, touchdown spaces, private offices or specialist workstations.
5. Separate individual work areas from shared rooms and support spaces.

A common office-space benchmark is 100 to 200 square feet per employee, depending on sector and working style. Hybrid models may reduce desk needs but increase shared-space requirements. Treat the benchmark as an initial test of your requirement, not as a specification for every City of London workplace.

British Council for Offices guidance recommends 10 to 12 square metres of net internal area per workstation as a working standard for a productive UK office. That measure covers the desk, nearby circulation and associated storage, but excludes meeting rooms, breakout spaces and reception. It therefore cannot be used as the complete area requirement for a hybrid workplace with substantial shared space.

Hybrid working tends to increase demand for meeting rooms and collaboration areas even as it reduces desk count. Your model should therefore show both the number of people the workplace must accommodate and the number of people expected to use desks at the same time.

Add the spaces that make the workplace workable

The workplace schedule should add the spaces that support work beyond individual desks. Include meeting rooms, breakout areas, reception, kitchen, storage, circulation, quiet areas and the technology needed for the intended layout.

A 4- to 8-person meeting room requires around 150 square feet. Larger boardrooms and reception areas may require 250 to 900 square feet, depending on layout and usage. These are planning figures, not fixed room sizes: state the function, occupancy and equipment requirement beside each space.

Workstation configuration affects more than the furniture order because the layout must coordinate with power, data, lighting, circulation and other workplace requirements. A change from permanent desks to shared workstations can therefore alter the infrastructure and technology brief as well as the furniture quantity.

Record these decisions before asking for an estimate:

• the number and purpose of meeting rooms;
• expected room occupancy and meeting frequency;
• breakout, collaboration and quiet-work requirements;
• kitchen, reception, storage and welfare requirements;
• whether existing desks and chairs will be retained;
• meeting-room technology, AV, data and wireless requirements;
• acoustic, lighting and finish expectations.

A basic refresh of an existing office is cited at nearer £40 to £65 per square foot, while a high-specification headquarters with feature joinery, enhanced mechanical and electrical services and acoustic treatment can exceed £150 per square foot. Those benchmarks reinforce the need to describe the spaces and quality you actually require rather than using labels such as basic or premium without detail.

Read current benchmarks as dated planning evidence

The available 2025 and 2026 benchmarks should be used as dated planning evidence, with the geography, specification, unit and inclusions kept beside every figure. They do not produce one reliable City of London price.

One 2026 UK guide gives all-in basic fit-outs at £45 to £85 per square foot, mid-range fit-outs at £85 to £135 per square foot and high-specification fit-outs at £135 to £200 or more per square foot. The stated all-in scope covers construction, services, furniture and technology.

A separate cited cost guide gives all-in London office fit-out costs of £148 per square foot for low specification, £243 per square foot for medium specification and £359 per square foot for high specification. The same source says contingency of 8% to 25% may sit on top depending on building age. Because this is a different guide with a different benchmark method, do not merge these figures with the UK guide into one range.

A 2025 global comparison analysing 50 locations reports an average high-specification London office fit-out cost of £4,671 per square metre, equivalent in the cited comparison to US$5,932 per square metre. That is a global comparison average for high specification, not a quotation for a particular City of London floor.

For a worked example, a source states that a 5,000 square foot office at the £85 to £135 per square foot mid-range specification would cost around £425,000 to £675,000 before VAT. The calculation is 5,000 square feet multiplied by £85 to £135 per square foot, and the cited broad all-in range covers construction, services, furniture and technology.

Another 2026 guide reports indicative all-in London benchmarks of £148 to £359 per square foot. A separate 2026 UK guide gives a typical Cat B range of £65 to £130 per square foot, or £700 to £1,400 per square metre. Keep each source’s scope and geography visible when using these figures.

Reconcile why published figures disagree

Published office fit-out figures disagree because they may describe different scopes, specifications, dates, geographies and cost bases. The right response is not to average them. Normalise them.

Check each benchmark or quotation against these questions:

• Does the figure cover construction only, or construction, services, furniture, IT and AV?
• Is it based on Cat A, Cat A+, an existing fitted office or another starting condition?
• Does it include design, surveying, project management and cost consultancy fees?
• Is VAT included or excluded?
• Are contingency, provisional sums and risk allowances included?
• Who supplies furniture, meeting-room technology and data infrastructure?
• What programme, access conditions and landlord requirements are assumed?

Professional-fee allowances vary by benchmark. One London fit-out cost guide indicates 10% to 15%, while another UK benchmark allows 12% to 18% of construction cost. These percentages have different stated scope and denominator, so confirm the included services and calculation base before comparing them.

A UK Cat B guide gives a range of £40 to £130 per square foot depending on specification and says furniture, IT and professional fees add significantly to that figure. A separate 2026 guide gives £65 to £130 per square foot for a typical UK Cat B fit-out, nearer £40 to £65 per square foot for a basic refresh, and more than £150 per square foot for a high-specification headquarters. These ranges should remain attributed to their respective guides.

The same 2026 source says London typically adds 15% to 25% to the stated outside-London Cat B fit-out cost. Treat that as a source-specific comparison, not a universal City of London adjustment. Normalise scope, design responsibility, exclusions, programme, risk and commercial qualifications before accepting a headline total.

Model the variables that move the total

The City of London fit-out total moves with the size and condition of the premises, the workplace specification, services complexity, access, landlord requirements and delivery programme. Model each variable rather than hiding it inside one rate.

Small floor plates need particular care. For an office of 1,500 to 4,000 square feet, the per-square-foot rate tends to be higher because fixed costs, minimum charges and facilities such as a kitchen or single meeting room are spread across less area. One source recommends budgeting towards the upper end of each range rather than the middle for an office in that size band.

Headline rates are usually based on large floor plates of 10,000 square feet and above. Below 10,000 square feet, the rate may increase because some facilities cost roughly the same whether they serve 15 people or 50. Do not apply a large-floor-plate benchmark without recording your actual area.

The main cost levers are:

• mechanical, electrical and plumbing infrastructure, including HVAC, lighting and data systems;
• meeting rooms, collaboration areas, bespoke joinery and higher finish levels;
• workstation numbers and the decision to retain or replace furniture;
• City-centre access, out-of-hours delivery, parking permits and possible labour-rate effects;
• landlord specifications for services, fire safety and sustainability;
• a compressed or phased programme;
• the procurement route and the point at which a contractor becomes involved.

Upgrading HVAC, lighting and data systems is one of the biggest fit-out cost drivers. City-centre access constraints may require out-of-hours delivery, parking permits and potentially increased labour rates. Compressed programmes or phased delivery can increase labour premiums, while early contractor engagement or design-and-build can shorten lead times.

Landlord-funded Cat A fit-out costs in London are cited at £35 to £80 per square foot, depending on building grade and mechanical and electrical infrastructure. Clarify what is landlord-funded and what remains your responsibility before using that allowance.

Turn the model into an indicative budget

The indicative budget should be a transparent calculation with an assumption beside every line. Start with early budgeting, a site survey, risk allowances and clear decision-making; these controls make the final office fit-out cost easier to manage.

Use this working method:

1. Confirm the floor area and whether it is measured in usable, net internal or another area basis.
2. Classify the starting condition: refresh, Cat A, Cat A+ or another baseline.
3. Describe the specification as functional, mid-range or high specification, with finishes and technology listed.
4. Multiply the selected planning rate by the relevant area.
5. Add separately stated furniture, IT, professional fees, contingency, VAT and other excluded lines.
6. Record landlord contributions, exclusions, provisional sums, programme and access assumptions.
7. Recalculate the total when headcount, rooms, finish level or technology changes.

For 2026, one guide says a functional low-spec Cat B space starts around £45 per square foot, while a high-specification flagship office can exceed £200 per square foot. The same source says professional fees typically add 10% to 15% to construction costs. Apply that fee allowance only when the selected benchmark is construction-based and the services are not already included.

A separate UK guide gives office fit-out costs of around £30 to £250 per square foot, depending on specification, building condition, location and level of finish. That broad range is a reminder to use the narrowest supported benchmark that matches your brief, not to present £30 to £250 as your personal budget.

One benchmark allows £15 to £40 per square foot for furniture, £8 to £20 per square foot for IT and data infrastructure, 12% to 18% of construction cost for professional fees and 10% to 15% of total project cost for contingency. These lines are benchmark allowances, not mandatory additions; first check whether your primary rate already includes them.

Build a programme alongside the budget

The office fit-out programme should distinguish time on site from the full period required to brief, design, approve, procure, construct and occupy the workplace. Floor area alone cannot provide a reliable duration. Starting condition, design information, approvals, services interfaces, procurement, access, occupied-working constraints and specialist packages all affect the programme.

Published planning durations use different boundaries:

• A typical mid-spec project might take 8 to 12 weeks from initial consultancy to handover. Bespoke finishes such as custom joinery or specialist lighting can add weeks to procurement if they are not managed early.
• Cat B fit-outs in conventional office buildings usually take 14 to 20 weeks overall: design takes 4 to 6 weeks, building-regulations approval takes 4 to 6 weeks concurrently, procurement takes 3 weeks and construction takes 8 to 10 weeks.
• A straightforward fit-out takes 8 to 14 weeks on site, while the full programme from first brief to people sitting at their desks commonly runs 5 to 8 months.

A cited London sequence applies to a mid-sized project of 5,000 to 15,000 square feet. Larger or more complex projects, and buildings with extensive heritage constraints, require additional time, especially for design and landlord approval. Construction time varies with the size and complexity of the space, and design-and-build and traditional procurement differ in construction-phase speed.

Build your own programme by naming each stage, its dependencies, the decision owner and the approval needed. That schedule is more useful than attaching one duration to floor area.

Prepare a like-for-like estimating brief

The estimating brief should describe how your team will use the workplace, what the premises provide and how the estimate must be presented. A detailed brief makes a broker, designer, surveyor or contractor more likely to price the same requirement rather than separate interpretations of it.

Include these sections:

• People and attendance: current headcount, realistic future growth, team structure, remote-working patterns and shared-workstation assumptions.
• Work settings: permanent workstations, shared desks, touchdown spaces, private offices, specialist workstations, quiet areas and collaboration zones.
• Room schedule: meeting-room quantities, capacities, purposes, boardroom or reception needs, breakout areas, kitchen, storage and welfare spaces.
• Existing assets: desks, chairs, fittings and equipment to retain, relocate, replace or dispose of.
• Technology: data, wireless, AV, meeting-room technology, comms rooms and power requirements.
• Quality and delivery: finish level, acoustic expectations, lighting, joinery, target occupation date, working-hours restrictions and access conditions.
• Commercial basis: area measurement, currency, VAT treatment, included and excluded items, landlord works, professional fees, contingency, provisional sums and risk allowances.

Headcount affects more than desks: it can change meeting rooms, circulation, storage, kitchen, breakout areas, power, data, lighting, furniture and total space. Workstation configuration must coordinate with the furniture order, power, data, lighting and circulation.

Use a detailed specification because differing contractor interpretations make quotations harder to compare. One quotation may include upgraded acoustic partitions or meeting-room technology while another assumes basic partitions or client-supplied technology. Normalise scope, design responsibility, provisional allowances, exclusions, programme, risk and commercial qualifications before comparing totals.

Carry out a workspace audit before the build begins and assess how your team uses the space, including quiet zones and collaborative hubs. Fit-out costs can vary by 10% to 30% across different office typologies and specifications. For reference, one London guide states that a high-specification Cat B fit-out costs £130 to £200 or more per square foot, approximately £1,400 to £2,150 or more per square metre.

Obtain qualified review before material commitments

The City of London fit-out should receive project-specific review before the budget, programme or premises decision becomes a material commitment. Significant works commonly require formal landlord approval, often through a Licence to Alter, but the exact requirement and process depend on the building, lease and proposed works.

Allow time for the approvals and investigations that apply to the premises.

London fit-outs involve regulatory, commercial and technical complexity, including CDM obligations, listed-building constraints and multi-party landlord approval.

Pause before committing funds or signing project or lease documents if the scope, responsibility, approvals, surveys, risk allowances or cost basis remain unclear. Obtain the relevant qualified design, surveying, cost, legal or compliance review for the issue that affects your project.

A completed requirements schedule supports an indicative discussion

A City of London fit-out budget can be used to record the area, capacity model, starting condition, specification, inclusions, exclusions, programme and risk assumptions behind the number. Use dated benchmarks to test the requirement, then compare estimates only after their scope and calculation basis have been aligned.

Before a material commitment, have qualified design, surveying, cost, legal or compliance professionals decide the issues that depend on the building, proposed works and project documents.

We help clients secure office space in the City of London by guiding them through finding and negotiating leases. A completed requirements schedule gives that discussion a defined basis.