This page covers the practical work of forming and registering a new business: incorporating the company at Companies House, the HMRC registrations, and setting up VAT, PAYE and the books. If you are still deciding whether to start, or between sole trader and limited company, those decisions are covered on our page for start-up accountants.

Starting a business is mostly about the idea, the customers and the hours you put in. The accounting side is smaller, but the decisions made in the first few weeks, such as the structure, the registrations and the way records are kept, shape your tax bill for years. We deal with that side from the first conversation, so you can get on with trading.

If you are looking for an accountant to help start a business, we work with new sole traders, partnerships and limited companies from our office in Finchley and online across London. The first meeting is about your plans: what you will sell and to whom, what you expect to earn in the first year, and whether you will employ anyone. From that we recommend a structure, handle the registrations and set up your bookkeeping, with the fee agreed in writing before any work begins.

We will help you to:

• decide on the most suitable structure for your business — sole trader, partnership, limited liability partnership or limited company
• prepare a business plan, cashflow projections, budgets, and trading forecasts
• assess the finance requirements, advise on the best sources of finance and draw up the necessary proposals
• establish a good working relationship with your bank
• complete any registration procedures with Companies House and HMRC
• deal with company secretarial issues
• set up a recording system for your internal use and for complying with statutory requirements
• decide on what computer hardware to buy and help with the installation of accountancy software
• keep on top of bookkeeping, VAT, payroll and other accounting requirements
• help with all aspects of business compliance and administration.

Your first 90 days: what we set up and when

• Structure: sole trader or limited company, decided on your figures rather than on general advice
• Sole traders: registration for Self Assessment, which must be done by 5 October after the end of the tax year in which you start
• Limited companies: incorporation at Companies House, identity verification for directors and people with significant control (required since 18 November 2025), corporation tax registration and your first year-end date
• PAYE: an employer scheme if you will pay staff, or pay yourself a salary as a director
• VAT: registration if taxable turnover will pass £90,000 in any rolling 12 months or is expected to within the next 30 days, or voluntarily if it helps you
• Records: a business bank account, cloud bookkeeping software with bank feeds, and a simple routine for receipts
• A deadline calendar, so you know every filing and payment date before it arrives

Sole trader or limited company: the numbers that decide it

As a sole trader your profit is taxed as income: the personal allowance of £12,570, then 20% up to £50,270, 40% above that and 45% over £125,140, plus National Insurance. It is simple to run, and very small side ventures may be covered entirely by the £1,000 trading allowance.

A limited company pays corporation tax on its profit, 19% up to £50,000 and 25% over £250,000 with marginal relief in between, and you are then taxed again on what you take out as salary or dividends. In exchange you get limited liability and more control over when income is taxed, but also more administration: accounts to Companies House within nine months of the year end, the CT600 return within 12 months, and the tax itself nine months and one day after the year end.

Software matters too. From 6 April 2026, sole traders and landlords with qualifying income over £50,000 must keep digital records and send quarterly updates under Making Tax Digital for Income Tax, with the threshold falling to £30,000 from April 2027 and £20,000 from April 2028. We set you up so you are ready before you need to be.

Mistakes new businesses make in the first year

• Running business and personal spending through one account, which makes the records slow and expensive to untangle
• Registering late for Self Assessment, then being surprised by a first 31 January bill that can include a payment on account for the following year
• Watching the VAT threshold by tax year instead of on a rolling 12 months. Register late and you owe VAT on sales you never charged it on
• Directors drawing money from a new company with no plan for salary and dividends, leaving an overdrawn loan account at the year end
• Keeping receipts in a drawer until the year end, when half of them are missing

None of these is unusual, and all of them cost money: a £100 penalty for a late return even when no tax is due, interest on late payments, and tax paid on expenses that could have been claimed with better records.

Start-up support that continues after launch

Once you are trading we stay with you: bookkeeping, VAT, payroll and your first year-end accounts and tax returns, with fees agreed in writing before work starts. You can reach us on WhatsApp or email, meet us at our office in Finchley, and work with us in English, Turkish, Persian or Italian.

• Start-up accountant in London
• Limited company accountant in North London
• Bookkeeping services
• Business structures: which should I use?
• Business plans
• Start-up costs calculator