After incorporating a UK limited company, tax registration quickly becomes one of the first practical jobs on the list. VAT and Corporation Tax are often mentioned together, but they work very differently. Corporation Tax registration is linked to the company becoming active, while VAT registration usually depends on taxable turnover. Understanding those triggers early can help you avoid missed deadlines and unnecessary admin.
For a new company, the most important point is not to assume that Companies House registration completes every HMRC registration automatically. You will normally receive a company Unique Taxpayer Reference, but you still need to make sure Corporation Tax is added correctly to your business tax account when trading begins. VAT is separate again and may not be required at all if your taxable turnover remains below the current threshold.
When Do You Need to Register for Corporation Tax?
A limited company generally needs to tell HMRC when it becomes active and falls within the charge to Corporation Tax. HMRC says this should be done within three months of the start of the company’s Corporation Tax accounting period.
In practice, a company is usually treated as active when it starts carrying on business activity, such as trading, providing services or otherwise operating with a view to making a profit. If the company was incorporated but has not started trading, it may remain dormant for Corporation Tax purposes until activity begins.
What You Need for Corporation Tax Registration
HMRC normally sends a 10-digit Corporation Tax Unique Taxpayer Reference to the company’s registered office after incorporation. If it has not arrived within around 15 working days, it can be requested from HMRC.
To add Corporation Tax services to the business tax account, you will usually need the company UTR, the company registration number and the date the first accounts are made up to. Keep the registered office address accurate because HMRC correspondence may be sent there.
There Is No VAT-Style Turnover Threshold for Corporation Tax
This is where many new directors get confused. Corporation Tax registration is not based on reaching a particular sales figure. A small company making modest profits can still have Corporation Tax obligations once it is active.
VAT works differently. A company can trade for some time without being VAT registered if its taxable turnover stays below the registration threshold and no other compulsory registration rule applies.
What Is the VAT Threshold in 2026?
The current compulsory VAT registration threshold is more than £90,000 of taxable turnover. This is not measured by calendar year or company financial year. It is normally tested on a rolling 12-month basis, so businesses should review turnover regularly rather than waiting until year-end.
Taxable turnover generally includes sales that are standard-rated, reduced-rated or zero-rated for VAT. It does not normally include supplies that are VAT exempt or outside the scope of UK VAT.
Two Ways the VAT Registration Trigger Can Arise
If You Exceed £90,000 in the Previous 12 Months
If taxable turnover for the previous 12 months goes above £90,000, you normally have 30 days from the end of the month in which the threshold was exceeded to register. Your effective date of registration is generally the first day of the second month after the threshold was crossed.
For example, imagine a new consultancy checks its rolling turnover on 20 September and discovers that taxable sales over the previous 12 months have reached £94,000 for the first time. The business should not wait until its next accounting year. The VAT registration deadline follows the specific HMRC timing rules from that September trigger.
If You Expect to Exceed £90,000 in the Next 30 Days
There is also a forward-looking test. If you realise that taxable turnover will exceed £90,000 in the next 30 days alone, you must register by the end of that 30-day period. In this situation, the effective date of VAT registration is normally the date you first formed that expectation.
This can matter when a young business wins one unusually large contract. You do not have to wait until the invoice is fully paid or until the rolling 12-month figure has already crossed the threshold.
Can You Register for VAT Voluntarily?
Yes. A business with taxable turnover below £90,000 can normally choose voluntary VAT registration if it makes, or intends to make, taxable supplies.
Voluntary registration can suit businesses that mainly sell to VAT-registered commercial customers or incur significant VAT on costs. However, it also creates extra administration and may make prices less attractive to customers who cannot recover VAT. The decision should be based on your customers, margins and expected input VAT rather than the idea that VAT registration automatically makes a company look more established.
What Happens After VAT Registration?
HMRC will confirm your VAT registration number, effective date of registration and information about your first VAT Return and payment. From the effective date, the business must account for VAT on relevant taxable sales and can normally reclaim eligible VAT on qualifying business purchases, subject to the usual rules.
New VAT-registered businesses are automatically signed up for Making Tax Digital for VAT unless they are exempt or have successfully applied for an exemption. That means VAT records should be kept digitally and VAT Returns submitted using compatible accounting software.
What Happens After Corporation Tax Registration?
Once Corporation Tax is set up, keep accounting records that allow the company’s taxable profit to be calculated correctly. For most companies with taxable profits up to the large-company instalment threshold, Corporation Tax is usually due nine months and one day after the end of the accounting period.
The Company Tax Return is normally due later, 12 months after the end of the accounting period. This difference catches some new directors: the tax payment deadline usually arrives before the return filing deadline.
A Simple Registration Checklist for a New Limited Company
After incorporation, confirm that the registered office is correct and watch for the company UTR. When trading starts, make sure Corporation Tax services are added and HMRC is told within the required three-month period. At the same time, monitor taxable turnover every month for VAT purposes rather than checking it only at year-end.
If turnover approaches £90,000, review both the previous 12 months and any large sales expected in the next 30 days. If you register for VAT, set up compatible accounting software, update invoicing processes and record the effective registration date carefully.
Useful related topics include choosing accounting software for a limited company, first-year company filing deadlines and understanding allowable business expenses.
Frequently Asked Questions
Do I register for Corporation Tax as soon as I incorporate?
Not necessarily on the incorporation date. The key point is when the company becomes active. Once it starts its Corporation Tax accounting period, HMRC should generally be told within three months.
What is the VAT registration threshold in the UK?
The current compulsory VAT threshold is more than £90,000 of taxable turnover. The usual test looks at the previous rolling 12 months, with a separate rule if you expect to exceed the threshold in the next 30 days alone.
Can a company register for VAT before reaching the threshold?
Yes. Voluntary VAT registration is possible below the threshold if the business makes or intends to make taxable supplies. Whether it is worthwhile depends on customers, costs and administrative impact.
Are VAT and Corporation Tax registered through the same process?
No. They are separate HMRC obligations with different triggers and registration steps. Being set up for Corporation Tax does not automatically mean the company is VAT registered.
Track the Triggers, Not Just the Deadlines
The easiest way to manage early tax compliance is to track the events that create each obligation. For Corporation Tax, that means knowing when the company becomes active. For VAT, it means monitoring taxable turnover and large upcoming contracts against the £90,000 threshold. Set up those checks from the start, keep your HMRC details organised and the registration process becomes a routine part of launching the business rather than a last-minute compliance problem.