Warrener Stewart

What Warrener Stewart does

Warrener Stewart is a UK chartered accountancy firm founded in 1983 and headquartered at Harwood House, 43 Harwood Road, London (Fulham), with a second office at 93 George Street, Edinburgh. It is constituted as Warrener Stewart Limited (company number 07513468), a private limited company registered to carry on audit work by the ICAEW, and operates a wholly-owned subsidiary, WSA Tax Limited, formed in 2023 to serve expatriate Americans with combined US and UK tax needs. Headcount is in the 11-50 band, with senior practitioners including chartered accountants, chartered tax advisors, US Enrolled Agents, and a CPA.

The firm delivers a full-service professional offering across accountancy (financial and management reporting, systems reviews, outsourced finance director), audit and assurance (statutory, voluntary, ATOL/ABTA, internal controls, grant audit), business advisory and planning (valuations, corporate finance, M&A, succession), and tax (corporation, personal including Making Tax Digital, international, and US). Service delivery relies on standard third-party accounting, tax, and payroll software plus a WordPress website with online bookings, with no proprietary technology platform or AI capability disclosed. Sector pages cover schools, professional practices, property, manufacturing, family businesses, UK subsidiaries of overseas parents, and retail, indicating deliberate vertical specialisation alongside general practice.

Revenue is generated through hourly professional-services fees tied to time, skill, complexity, and risk, with fixed-fee estimates available for defined scopes. The go-to-market is sales-led and relationship-based, combining direct advisory targeting owner-managed businesses with referral, content marketing (tax updates, Spring/Autumn Statements), and long-standing community engagement via Rosslyn Park FC sponsorship. Customer base skews to SMBs across the UK, with selective enterprise work (e.g., Vattenfall UK), and no segment, ARR, or revenue concentration data is publicly disclosed.

Name

Warrener Stewart

Legal name

Warrener Stewart Limited

Website

https://warrenerstewart.com

Company type

Private

Founded year

1983

Operating status

Operating

Headcount range

11–50 employees

Short description

Warrener Stewart is a UK chartered accountancy firm serving owner-managed businesses and SMBs with accountancy, audit, advisory, and tax (UK, international, and US-expat) services from offices in Fulham, London and Edinburgh, with a wholly-owned US-tax subsidiary, WSA Tax Limited.

Ownership category

akta.pro rank

Headquarters

HQ city

London

HQ country

United Kingdom

HQ region

Europe

Offices2 records

Markets served

GTM type

B2B

Offering type

Services

Cost components

Personnel, Operations, Technology or R&D, Marketing or Sales, Infrastructure

Revenue model

1. Professional Services Fees: Hourly-based professional services fees for accounting, audit, tax advisory, and business advisory services. Fees depend on time spent, skill level, responsibility, importance and value of advice, and level of risk. Fixed fees may be quoted for specific services upon request.

Pricing tiers

Go-to-market motion2 records

Distribution channels2 records

Marketing channels4 records

Core offering

Warrener Stewart is a chartered accountancy firm providing accountancy, audit and assurance, business advisory, business planning (valuations, M&A, succession), corporation tax, personal tax, international tax, US tax, support services (VAT, payroll, bookkeeping, company secretarial) and expert witness services. Deliveries are made by qualified principals to owner-managed businesses, small enterprises and mid-sized corporates across two offices in London and Edinburgh, with a specialised WSA Tax Limited subsidiary serving expatriate American clients.

Product overview

Warrener Stewart is a traditional chartered accountancy firm offering a comprehensive suite of professional services rather than a software product. The core offering consists of accountancy, audit and assurance, business advisory, and tax services (corporate, personal, international, and US tax) delivered through experienced chartered accountants, chartered tax advisors, and registered auditors. The firm also provides supporting services including VAT, payroll, bookkeeping, and company secretarial. WSA Tax Limited operates as a separate subsidiary specializing in US and UK tax services for expatriate Americans. Services are offered across two physical office locations in Fulham (London) and Edinburgh.

Differentiator

Problem solved

Functional benefit

Brands

• WSA Tax Limited: Separate company offering US and UK tax services for expat Americans based in the UK

Products and services

• Accountancy Services Full range of accountancy services including financial reporting, management reporting, systems reviews and outsourced finance director services, designed for owner-managed businesses and SMEs without strong in-house finance teams.
• Audit and Assurance Services
• Business Advisory Services
• Business Planning Services
• Corporation Tax Services
• Personal Tax Services
• International Tax Services
• US Tax Services
• Support Services
• Expert Witness Services
• WSA Tax Limited Separate wholly-owned company offering combined US and UK tax services for expatriate Americans based in the UK, providing US and UK tax return preparation, filing and advisory delivered by dual-qualified specialists.

Quantifiable outcome

• 86% of clients rate service as good or excellent value for money
• +2 more outcomes

Named customers12 records

Ideal customer profiles3 records

Technology focussed No

API detail

Has API

No

API docs

API detail

Core technology

AI maturity

App detail

Partnerships

Four partnerships are on record, tiered minor and core.

• LGT Wealth ManagementminorGTM or Marketing Partner · 1 January 2022LGT Wealth Management invited Warrener Stewart's US Tax team to participate in an American football event, providing networking opportunities with their clients and contacts.
• EasyTipminorStrategic or Co-development Partner · 1 January 2020EasyTip is a client of Warrener Stewart that manages a leading cashless tipping platform used by service industry businesses. Warrener Stewart has worked with EasyTip since the company was formed in 2020, providing business advisory services, company accounts, UK payroll and corporation tax obligations. James Shepherd contributed expert guidance on new tipping regulations for their blog.
• Glass DoorminorOthers · 1 January 2015Glass Door is a London-based charity coordinating the UK's largest network of open-access services for people affected by homelessness. Warrener Stewart has made annual Christmas donations to support their work providing shelter, meals, and casework services to homeless individuals.
• Rosslyn Park FCcoreGTM or Marketing Partner · 1 January 2015Rosslyn Park FC is a rugby union club founded in 1879, based in Barnes, South West London. Warrener Stewart has been a sponsor since the firm's inception over 40 years ago. They sponsor the men's first team and individual players including Freddie Roddick. The firm also provides financial advice to the club.

Scale indicators4 records

Recent moves7 records

Expansion highlights5 records

Emerging players

• American Tax Returns Ltd (UK-based US tax specialists): Boutique UK firm specialising in US tax for US persons living in the UK; competes head-on with WSA Tax Limited rather than the broader Warrener Stewart practice, useful as a niche benchmark.

Direct peers

• Lubbock Fine: Mid-sized London chartered accountancy practice focused on entrepreneurial owner-managed businesses and SME advisory; directly comparable on size, audience and the relationship-led principal-access model.
• Barnes Roffe LLP: London and Home Counties chartered accountancy firm serving SMBs, owner-managed businesses and not-for-profits with audit, tax and advisory services — comparable scope, client profile and delivery style.
• HW Fisher & Company: London-based chartered accountancy firm of comparable size serving owner-managed businesses, SMEs and mid-corporates across audit, tax and advisory — overlapping Warrener Stewart on client segment, service mix and London geography.
• RPG Chartered Accountants: London chartered accountancy practice focused on owner-managed businesses and SMEs across audit, tax and advisory — directly comparable on size, client segment and service breadth.

Broad incumbents

• Kreston Reeves: UK top-40 chartered accountancy network with a comparable owner-managed and SME audit/tax/advisory proposition; overlaps with Warrener Stewart on client archetype while operating at meaningfully greater scale.
• MHA (MacIntyre Hudson): UK top-20 chartered accountancy and advisory group whose SME and owner-managed business practice competes head-on with Warrener Stewart, though with substantially broader geographic coverage.
• Moore Kingston Smith: Larger UK top-30 accountancy and advisory firm with a strong owner-managed and not-for-profit practice; competes for the same London SME/mid-corporate clients but with significantly greater scale.
• Crowe UK: Top-10 UK accounting network offering audit, tax and advisory; overlaps on owner-managed and mid-market audit, but at national scale and with international affiliations beyond Warrener Stewart's footprint.

Regional players

• Milsted Langdon: South West England chartered accountancy firm with a similar owner-managed/SME audit-tax-advisory mix; serves a similar clientele profile and scale but a different regional market.

Market position

Strengths4 records

Weaknesses4 records

Competitive moat4 records

Key risks6 records

Key highlights6 records

Customer concentration

Compliance1 record

Revenue estimate

Valuation estimate

Number of profiles

Profiles12 records

Subsidiaries1 record

Funding overview

Funding rounds

Investors

Funding detail is available on the Subscription and Enterprise plan.Contact sales →

M&A

Investments

M&A and investment is available on the Subscription and Enterprise plan.Contact sales →

Frequently asked questions about Warrener Stewart