The top 25 UK architecture firms, 2026

The UK's biggest architecture and design practices ranked by the turnover in their own filed Companies House accounts — not survey returns. The famous names that don't disclose revenue are named rather than guessed at, and practices that consolidate global work through their UK filings are footnoted as such.

£1.88B combined fees, top 31 practices
11,060 architects & designers employed
30% of it billed by Foster + Partners alone

What the filings show

British architecture is Foster + Partners and everyone else: £571M (up 55% on a year of Middle East megaprojects) against £1.31B for the other 30 practices combined. No other list in this franchise has a leader this dominant — and its filing consolidates the practice's global work, which the footnote says plainly.

Below the outlier, the profession is specialist and lean: stadium architects (Populous, +21%), heritage (Purcell), aviation (Pascall + Watson), hospitality (WATG), residential (HTA, PRP) — 7 tagged specialisms in all. Fees per head run £80–150k and the famous studios are smaller businesses than their reputations suggest: Zaha Hadid at £83M, Heatherwick at £37M.

The growth table — Foster + Partners (+55%), WATG UK (+50%), Bryden Wood (+32%), Scott Brownrigg (+31%) — tracks where the work is: international sport, infrastructure and the Gulf. The honest gap: several of Britain's most celebrated practices simply don't disclose revenue (small-companies regime), so Make, Sheppard Robson and Hawkins\Brown sit in the can't-rank list — a survey would guess; filings don't let us.

Top 25 architecture firms in the UK by filed turnover

Latest accounts filed as of August 2026 · refreshed monthly

# Firm Turnover YoY Staff Accounts
01 Foster + Partners International architecture and design practice The global practice’s consolidated filing — over three times the size of any other UK architect. £571M +55% 1,930 FY to Apr 2025
02 Populous architecture (sport & venues) Global Architectural Design Firm The EMEA business of the stadium specialist. £164M +21% 436 FY to Dec 2024
03 BDP multidisciplinary design International Architectural and Engineering Firm Building Design Partnership — owned by Japan’s Nippon Koei. £130M -13% 1,234 FY to Jun 2025
04 Dar Al-Handasah UK multidisciplinary design UK design office of the Dar Group (which also owns Perkins&Will and Currie & Brown). £127M +22% 1,194 FY to Dec 2024
05 Zaha Hadid International Architectural Design Practice Zaha Hadid Limited, consolidated. £83M +8% 503 FY to Apr 2025
06 Gensler Europe Architectural Design Firm UK-registered European business of the world’s largest architecture firm. £75M +2% 313 FY to Mar 2025
07 TP Bennett TP Bennett LLP, consolidated. £48M +11% 334 FY to Mar 2025
08 AHMM Employee-Owned Architecture Firm Allford Hall Monaghan Morris — employee-owned. £46M -3% 407 FY to Mar 2025
09 Benoy architecture (retail & masterplanning) Architectural and Urban Planning Firm £43M +8% 433 FY to Dec 2024
10 Allies and Morrison Allies and Morrison LLP. £37M -17% 286 FY to Mar 2025
11 Heatherwick Studio design studio International Architecture and Design Studio £37M -13% 221 FY to Mar 2025
12 Ryder Architecture International Architectural Design Firm £36M +14% 330 FY to Apr 2025
13 Pascall + Watson architecture (aviation) International Aviation Architectural Practice £35M +7% 245 FY to Dec 2025
14 Hopkins Architects Prominent British architectural firm £35M -1% 165 FY to Mar 2025
15 WATG UK architecture (hospitality) UK Architectural Design Practice Wimberly Allison Tong & Goo’s UK company. £34M +50% 167 FY to Dec 2024
16 Corstorphine & Wright Private limited architectural practice £34M +15% 310 FY to Jun 2025
17 Stride Treglown Stride Treglown Group plc, consolidated — employee-owned. £33M 334 FY to Dec 2025
18 Bryden Wood design & technology Architectural and engineering consultancy £31M +32% 226 FY to Mar 2025
19 Purcell architecture (heritage) Employee-owned architectural design practice Purcell Architecture Limited. £30M +14% 323 FY to Apr 2025
20 BIG Partners Bjarke Ingels Group’s London company. £28M -17% 162 FY to Dec 2024
21 Scott Brownrigg £28M +31% 168 FY to Jan 2025
22 KPF London Kohn Pedersen Fox’s UK registration of its international practice. £27M -5% 127 FY to Dec 2025
23 RSHP Rogers Stirk Harbour + Partners’ group company. £27M +5% 173 FY to Dec 2024
24 Broadway Malyan £23M +22% 99 FY to Apr 2025
25 EPR Architects £22M +9% 164 FY to Mar 2025

The next 6

Firms ranked 26–31

26 Grimshaw £20M +15% FY to Sept 2025
27 HTA Design architecture (residential) £19M -4% FY to Mar 2025
28 PLP Architecture £17M +5% FY to Dec 2024
29 HOK London £16M -8% FY to Dec 2024
30 PRP architecture (residential) £15M +6% FY to Mar 2025
31 Feilden Clegg Bradley £13M -12% FY to Mar 2025

The firms we can't rank

Architecture's missing names are small-companies-regime filers — famous practices, financially invisible.

How this list is built

Source. The latest annual accounts each firm filed at Companies House. Where a firm files consolidated group accounts, the group figure is used; the entity ranked is named under each firm. Where a firm filed a transition period longer or shorter than twelve months (flagged in the Accounts column), the table shows the filed figure but the firm is ranked on its annualised equivalent.

Who counts as an architecture firm. Architecture and design practices, tagged by specialism. Engineering consultancies (our engineering list), framework JV vehicles and design teams consolidated inside engineering groups are excluded.

Scope. UK-registered filings. UK-headquartered global practices (Foster + Partners, Zaha Hadid) consolidate international work in their filings — footnoted; US-headquartered firms (Gensler, HOK, KPF, BIG) appear through their UK companies only. This is the most LLP-heavy list in the franchise: five of the ranked practices carry no SIC code at all and would be invisible to a category search.

Cadence. Rebuilt monthly as new accounts land. Spot a practice we've missed or misread? Tell us — the methodology only works if it's challenged.

Quick answers

What is the biggest architecture firm in the UK?
Foster + Partners, and it isn't close: £571M in its latest filed accounts — more than three times the next practice, and not far off the rest of the top 25 combined (£1.31B across 30 firms).
Why are famous practices missing?
Architecture is small-business Britain at its most extreme: celebrated practices like Make, Sheppard Robson and Hawkins\Brown file under the small-companies regime with no turnover disclosed, so no honest list can rank them. They're named in the firms we can't rank.
Do these figures include international work?
Where a practice consolidates globally through its UK filing — Foster + Partners, Zaha Hadid, Populous's EMEA arm — yes, and the notes say so. The US giants (Gensler, HOK, KPF, BIG) appear through their UK-registered companies only.
Why is this list shorter than the others?
Disclosure, not size: 25 ranked firms (plus 6 more below the line) is what filed accounts with turnover support in this profession. The RIBA top-100 surveys cover more firms — by asking them, not by auditing them.