VAT Registration Troubleshooting Guide UK (2026)
Registering for VAT online with HMRC should be a simple digital process, but in practice many UK businesses face repeated errors, system outages, blocked submissions, and unexplained delays. One of the most common messages applicants see is “Service is not available”, which can be frustrating and confusing.
This complete guide explains why VAT registration fails, how to fix each problem step-by-step, when to wait, when to retry, and when to contact HMRC or switch to a paper application.
Who This Guide Is For
This guide is designed for:
- Sole traders
- Limited companies
- New startups
- Businesses registering voluntarily
- Businesses forced to register after crossing the VAT threshold
- Anyone stuck on the HMRC VAT registration page
Step 1: Check Whether HMRC VAT Services Are Down
Before changing anything, confirm whether HMRC’s system is temporarily unavailable.
HMRC regularly performs:
- Overnight maintenance
- Weekend system updates
- End-of-month processing
- Peak-time throttling
This can cause the VAT registration service to fail even if your details are correct.
What to do
- Log out
- Wait 30–60 minutes
- Try again early morning (6–8am) or late evening (after 9pm)
Outbound link:
https://www.gov.uk/government/organisations/hm-revenue-customs
Step 2: Use the Correct Government Gateway Account
A very common problem is using the wrong type of Government Gateway account.
Common mistakes
- Using an agent’s Gateway instead of a business Gateway
- Using a personal Gateway for a limited company
- Using an old or partially activated Gateway account
Correct setup
- Sole traders → personal Government Gateway
- Limited companies → business Government Gateway
- Directors must log in as the company, not as an individual
Outbound link:
https://www.gov.uk/log-in-register-hmrc-online-services
Step 3: Confirm Your Government Gateway Is Fully Activated
If your Government Gateway account is new, HMRC may not yet allow VAT registration.
Why this happens
- Identity checks incomplete
- Email or phone number not verified
- Two-factor authentication not confirmed
What to do
- Log in to Government Gateway
- Go to “Manage account”
- Check for any pending security or identity actions
- Complete all verification steps
VAT services remain blocked until this is done.
Step 4: Add VAT as a Service (Critical Step Many Miss)
Many users assume VAT is automatically available — it is not.
You must manually add VAT as a service.
How to add VAT
- Log into Government Gateway
- Go to your HMRC dashboard
- Select “Add a tax, duty or scheme”
- Choose “VAT”
- Follow the prompts
If VAT is not added, the registration form will fail or crash.
Outbound link:
https://www.gov.uk/register-for-vat
Step 5: Clear Browser Cache & Try a Different Browser
Browser conflicts are extremely common with HMRC systems.
Best browsers
- Google Chrome
- Mozilla Firefox
Avoid
- Old versions of Edge
- Internet Explorer
- Mobile browsers
Fix
- Clear cookies and cache
- Open a private/incognito window
- Disable ad-blockers
- Retry submission
Many users report success immediately after this step.
Step 6: Avoid Peak HMRC Traffic Times
HMRC systems slow down during:
- 9am–5pm weekdays
- Mondays
- End of month
- VAT deadline days
Best times to apply
- Early morning (6am–8am)
- Late evening (9pm–12am)
- Mid-week (Tuesday–Thursday)
Step 7: Check Your Business Details Carefully
Incorrect or inconsistent information can cause silent failures.
Common data issues
- Business start date too recent
- Turnover figures not matching expectations
- SIC code missing or incorrect
- Address mismatch with Companies House
- Director details incorrect
HMRC systems cross-check details automatically.
Outbound link:
https://www.gov.uk/set-up-business
Step 8: VAT Registration Fails at Submission Stage
If the form loads but fails on submission, the issue is usually backend-related.
Possible causes
- HMRC maintenance
- Gateway timeout
- Session expired
- Server overload
What to do
- Save progress
- Log out completely
- Wait at least 30 minutes
- Retry from a new session
Do not repeatedly click “Submit” — this can lock your session.
Step 9: HMRC Says “Service Not Available” Repeatedly
This is one of the most common complaints.
What it usually means
- HMRC VAT system temporarily unavailable
- Account permissions incomplete
- VAT service not fully activated
Action plan
- Log out
- Wait 1 hour
- Clear cache
- Retry in incognito mode
- Try a different device/network
If it persists for 48+ hours, contact HMRC.
Step 10: Contact HMRC VAT Helpline
If online registration repeatedly fails, HMRC must intervene.
VAT Helpline
- Phone: 0300 200 3700
- Overseas: +44 2920 501 261
Have ready
- Government Gateway ID
- UTR number
- Company number (if limited)
- Error message wording
HMRC can:
- Check service availability
- Unlock your account
- Add VAT service manually
- Advise paper registration
Outbound link:
https://www.gov.uk/contact-hmrc
Step 11: When to Use Paper VAT Registration
If online registration is impossible, HMRC may advise paper registration.
Paper forms
- VAT1 (UK businesses)
- VAT1TR (transfer of business)
Paper registration is slower but valid.
Outbound link:
https://www.gov.uk/government/publications/vat-application-for-registration-vat1
Step 12: Expected VAT Registration Delays (2026)
Processing times vary.
Typical timelines
- Online registration: 2–4 weeks
- Manual review: 4–8 weeks
- Paper application: 6–10 weeks
HMRC may request extra documents, which pauses processing.
Step 13: What to Do While Waiting for VAT Number
You must still:
- Track VAT on sales
- Keep VAT invoices
- Charge VAT from your effective date
You cannot issue VAT invoices until your number arrives, but VAT is still due.
Step 14: Common Reasons VAT Applications Are Rejected
Rejections are rare but increasing.
Reasons include
- Artificial business splitting
- Unclear trading activity
- Incorrect turnover expectations
- Suspicion of VAT abuse
- Incomplete information
Rejected applicants may need to reapply or provide evidence.
Step 15: Avoid VAT Penalties During Registration
Late registration penalties apply if you exceed the threshold.
How to protect yourself
- Apply as soon as threshold is exceeded
- Keep proof of application attempts
- Save screenshots of errors
- Contact HMRC promptly
HMRC may reduce penalties if delays were system-related.
Outbound link:
https://www.gov.uk/vat-registration/penalties
Step 16: When to Use an Accountant
An accountant can:
- Register VAT correctly
- Avoid costly mistakes
- Handle HMRC communication
- Choose the right VAT scheme
This is especially useful for:
- Limited companies
- Online sellers
- Import/export businesses
- Flat Rate Scheme users
Outbound Links (Official Resources)
VAT registration:
https://www.gov.uk/register-for-vat
HMRC contact:
https://www.gov.uk/contact-hmrc
VAT penalties:
https://www.gov.uk/vat-registration/penalties
Making Tax Digital:
https://www.gov.uk/guidance/vat-making-tax-digital
Add these to your site:
- VAT Explained UK 2026 – /vat-explained-uk-2026/
- Accountant Fees UK 2026 – /accountant-fees-uk-2026/
- Self-Employed Tax Return Cost UK 2026 – /self-employed-tax-return-cost-uk-2026/
- Business Bank Account Cost UK 2026 – /business-bank-account-cost-uk-2026/
- Cost of Running a Business UK 2026 – /cost-of-running-a-business-uk-2026/
