Mistakes made setting up a UK company
What these mistakes have in common is that each comes from missing a published rule. The costliest are VAT registration, whether the registered office qualifies, and the filing calendar, and all three are decided at set-up.
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Registering a company is straightforward; what is expensive is a rule that applied from day one and was not read. The registration steps themselves are at UK company formation.
01
What is the most common VAT registration mistake?
A business not established in the UK that supplies goods or services here registers for VAT whatever its turnover. GOV.UK sets that requirement independently of the £90,000 turnover threshold, which applies only to established businesses.
02
When is a registered office rejected?
A registered office has to be a physical address in the UK and in the country the company is registered in. It also has to be appropriate: delivery of a document there must be capable of being acknowledged.
An address that cannot acknowledge delivery fails the test, and Companies House can act against a company whose registered office does not qualify. This is checked at registration and afterwards.
03
Why are filing deadlines missed?
The commonest reason is assuming payment and return fall on the same date. Corporation tax is paid 9 months and 1 day after the accounting period ends, and the return is filed a full 12 months after it ends.
Three months separate the two, and the payment comes first. A founder working from the return date alone is three months late on the payment before anything is filed.
04
Does registering a company give a right to live in the UK?
It does not. Registration at Companies House is a commercial record and creates no immigration status on its own; the right to live and work in the UK comes from a visa route assessed entirely separately.
The route for founding a business is set out at the UK Innovator Founder visa, and it turns on an endorsement rather than on a company being registered.
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05
How does a second company affect tax?
The £50,000 and £250,000 corporation tax profit thresholds are not fixed: they are reduced proportionally by the number of associated companies. Setting up a second company therefore lowers the thresholds that apply to the first one.
Splitting activity across two companies to stay under a threshold generally has the opposite effect, because the thresholds move with the count. Whether two companies are associated is a technical test for an accountant.
06
What does British Global do at this stage?
British Global reads your plan against these five items: it sets out in a written preliminary report which of them apply to your company and refers you to an accountant whose professional membership is verified on a register.
Accountancy and tax work is carried out by a professional whose membership is verified on a public register; British Global sets out the position and refers.
07
Frequently asked questions
Does the £90,000 VAT threshold apply to everyone?
No. A business not established in the UK registers for VAT whatever its turnover, so the threshold does not apply to it.
Does a company registration help with a visa?
No. Companies House registration is a commercial record and creates no immigration status. The business route is the Innovator Founder visa, which turns on an endorsement.
Is a second company a way to lower tax?
Generally not. The corporation tax thresholds are reduced in proportion to the number of associated companies.
Sources
- GOV.UK — A business not established in the UK that supplies goods or services in the UK must register for VAT regardless of turnover; the £90,000 threshold applies to established businesses. — 26 August 2026
- GOV.UK — A registered office must be a physical address in the UK, in the country of registration, and must meet the appropriate address test. — 26 August 2026
- GOV.UK — The £50,000 and £250,000 corporation tax profit thresholds are reduced in proportion to the number of associated companies. — 26 August 2026
- GOV.UK — The corporation tax return is due 12 months after the end of the accounting period, while payment is due at 9 months and 1 day. — 26 August 2026
