Verified AccountantsUK firms, verified against the public record
Simplex Accounting Limited website icon

Simplex Accounting Limited

Accountant in London E1

Verified & RegulatedTrust Score95/100Excellent

Companies House: 142101665 Brayford Square, London, E1 0SGData updated 07 Jul 2026

Formerly known asIsle Book-keep Limited

In the local market

Simplex Accounting Limited is one of 4856 accountancy practices we verify in London. It advertises a wider range of services than most firms we list in London.

Verified Accountants assessment

Simplex Accounting Limited is a UK limited company based in London, incorporated in 2022 and trading for 4 years.It was previously known as Isle Book-keep Limited.

Public records confirm it is anti-money-laundering supervised by AAT, up to date with its accounts (last filed 31 Jul 2025), and running a confirmed website. Its most recent filed accounts, for the year to 31 Jul 2025, report net assets of £4,789, down from £7,976 the year before. Its website shows it handles Small business, Self Assessment, VAT, and Payroll and works with Xero, QuickBooks, and Sage.

How we verify →

Verification record and Trust Score

95/100

Trust Score

Excellent
Public record
AML supervised · AAT
Active company
Filing compliant
Trading 4 years
Companies House ACSP
Professional qualification
  • ICAEW
  • ACCA
  • AAT
Contact
Website
Phone
Email

The Trust Score is the share of the applicable public signals we have verified, scored out of 100 - fully deterministic, never subjective. How it is scored, and every signal's points →

Companies HouseActiveno. 14210166 (opens in new tab)incorporated 2022Companies House · checked 07 Jul
Registered activity
  • SIC 69201 - Accounting and auditing
  • SIC 69202 - Bookkeeping
  • SIC 70221 - Financial management advice
The business activity the firm registered with Companies House (its Standard Industrial Classification).Companies House · checked 07 Jul
Filing complianceAccounts and confirmation statement filed on timelast accounts 31 Jul 2025 (opens in new tab)Companies House · checked 07 Jul
Anti-money-launderingSupervised by AATAAT is one of the professional bodies approved to supervise accountants for anti-money-laundering. Every UK accountant must be supervised, by HMRC or an approved professional body, so this confirms the firm is monitored and operating legitimately.AAT · checked 17 Jul
Companies House ACSPAuthorised Corporate Service ProviderRegistered on the Companies House Authorised Corporate Service Provider list - permitted to file, and verify client identities, at Companies House on behalf of clients.Companies House · checked 25 Jul
Sources: Companies House (opens in new tab), AAT
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Good fit for

  • Works in Xero, QuickBooks and Sage
  • Handles Small business, Self Assessment, VAT and Payroll

Specialisms and services

Certified
Xero Silver Partner - since 2021
Services
AccountantSmall businessSelf AssessmentVATPayrollBookkeepingLimited company accountsCIS
Software
QuickBooksSage

Message this firm

Send an enquiry and we will pass it to Simplex Accounting Limited. No account needed - just your contact details and what you need help with.

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Registered address

Shared with 41 companies registered at this address (London Virtual Office Service). An address used by this many companies is a shared, serviced or virtual office - not a dedicated one.

See all 41 companies at this address

People at Simplex Accounting Limited

Persons with significant control (1)

  • Miss Lucy Marie JohnsonOwns 75-100% of shares, 75-100% of voting rights, Can appoint or remove directors

Source: Companies House register (opens in new tab).

Financials (as filed)

Companies House filing history (opens in new tab) | 2023 to 2025
Net assets
£4.8k
as at 31 Jul 2025-£3.2k vs 2024
Current assets
£11k
as at 31 Jul 2025-£1.1k vs 2024
Average employees
2
as at 31 Jul 2025-2 vs 2024
Current assets (cash, debtors, other) and net assets by year, in £. Latest year first.
202520242023
CashDebtorsOtherNet assets
Full figures
As filed31 Jul 202531 Jul 202431 Jul 2023
Average employees241
Net assets£4,789£7,976
Current assets£11,346£12,413£24,788
Fixed assets£886£1,374£1,419
Shareholders equity£4,789£7,976£18,770

Figures as reported in this firm's accounts filed at Companies House. Net assets is total assets less what the company owes; a figure below zero means recorded liabilities exceed assets. Small companies may file abbreviated accounts that omit turnover and profit. Public record, reproduced as facts.

Timeline

  1. 2022Company incorporated
  2. 2025Latest accounts filed
  3. 2026Verified on this directory

Frequently asked questions

Is Simplex Accounting Limited a regulated accountant?

Yes. Simplex Accounting Limited is supervised for anti-money-laundering by AAT. Every UK accountant must be supervised for anti-money-laundering, by HMRC or an approved professional body, so this confirms the firm is authorised to practise and monitored for compliance.

What services does Simplex Accounting Limited offer?

Based on its own website, Simplex Accounting Limited offers Small business, Self Assessment, VAT, Payroll, Bookkeeping, and Limited company accounts. Confirm current services and availability with the firm before engaging. Message this firm →

What accounting software does Simplex Accounting Limited use?

Simplex Accounting Limited is Xero (Silver partner), so it works with Xero. Certified partners are trained on the software and listed in the vendor's own advisor directory.

How long has Simplex Accounting Limited been established?

Simplex Accounting Limited was incorporated at Companies House in 2022, so it has been on the register for about 4 years. A longer trading history is one sign of an established, accountable firm, though a newer firm is not necessarily less capable.

Does Simplex Accounting Limited file its accounts on time?

Yes. According to Companies House, Simplex Accounting Limited's most recent statutory accounts were filed by their due date. On-time filing is a basic sign that a company is being administered properly.

How do you verify Simplex Accounting Limited?

We build this record only from public, authoritative sources - for this firm, Companies House and AAT, and stamp every claim with its source and the date we last checked it. We show only what we can verify and say so plainly when we cannot. How we verify →

How is the Trust Score calculated?

The Trust Score is fully deterministic: fixed points for public, verified signals - an active company, anti-money-laundering supervision, filing compliance, a confirmed website and trading history. Simplex Accounting Limited scores 95/100. Nothing in the score is subjective, and every rule is listed on this page. How we verify →

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