Integration · Company data
Connect Claude & ChatGPT to HMRC VAT Check
Ask your AI whether a UK VAT number is valid and who it is registered to. It checks the number with HMRC's Check a UK VAT Number service and returns the registered business name and address. If you give your own VAT number, it also gets an HMRC consultation reference you can keep as proof of the check.
Free plan, no credit card. Takes about a minute.
Try asking
“Is VAT number 123456789 valid?”
The AI checks the number with HMRC and tells you whether it is a valid UK VAT registration number.
“Who is VAT number 123456789 registered to?”
It returns the business name and address HMRC holds for that number.
“Check this supplier's VAT number and give me a reference I can file.”
It checks the number with your own VAT number as the requester and returns HMRC's consultation reference.
What your AI can do
Validity check
Check whether a 9-digit UK VAT registration number is valid.
Name and address
Get the business name and address registered with HMRC for the number.
Proof of the check
Add your own VAT number to get an HMRC consultation reference for your records.
“Does the company name on this invoice match its VAT number?”
It gets the registered name and address for the number, so you can compare them with the invoice.
“Check the VAT numbers of these five new customers.”
It checks each number in turn and lists which are valid, with the registered name and address.
“We last checked this number a year ago. Is it still valid?”
It runs a new check against HMRC and returns the current result.
2 tools for HMRC Check a UK VAT Number
These tools are switched on when you connect. You can switch any of them off, or require your approval before it runs.
check_vat_numberCheck whether a UK VAT registration number (`target_vrn`, 9 digits) is valid and get the registered business name and address.check_vat_number_with_referenceCheck a UK VAT number (`target_vrn`) and get an HMRC consultation reference as proof of the check. `requester_vrn` is your own business's VAT number.
Set up in three steps
- 1
Pick the app
Create a free PipMCP account and choose HMRC Check a UK VAT Number from the app list.
- 2
Paste your key
Paste the production Client ID and Client secret from your HMRC Developer Hub application. Create an application, subscribe it to Check a UK VAT Number (v2), test in the sandbox, accept the terms of use and request production credentials. HMRC says this takes around 2 weeks.
- 3
Add the link to your AI
You get a personal MCP link. Add it to Claude, ChatGPT or Cursor:
- Click your name, then Settings › Connectors › Add custom connector.
- Paste your link as the Remote MCP server URL.
- Switch it on from the + menu in a chat.
Questions
What can the AI do in HMRC VAT Check?
It can check whether a UK VAT number is valid and get the business name and address registered to it. With your own VAT number as the requester, it can also get an HMRC consultation reference as proof of the check.
Does the AI see my HMRC VAT Check credentials?
No. Your HMRC VAT Check credentials are encrypted at rest and never shown to the AI. After you save them, they are not shown again, not even to you. The AI only sees the results of the tools it calls.
Can I control what the AI is allowed to do?
Yes. You choose which of the two tools are switched on. Both only check VAT numbers and read the result, so nothing is changed at HMRC. Every tool call is logged.
Does it work with ChatGPT?
Yes. In ChatGPT, open Settings › Apps & Connectors › Advanced, turn on Developer mode and add your PipMCP link. Developer mode needs a paid ChatGPT plan: Plus, Pro, Business or Enterprise. The same link also works in Claude (Settings › Connectors › Add custom connector), Cursor and other MCP clients.
What does it cost?
HMRC's API connects with OAuth, and OAuth connections need the PipMCP Pro plan or above. PipMCP also has a free plan with no credit card, but it does not include this connection. Paid plans bill per completed task. You also need production credentials from the HMRC Developer Hub.
What is a consultation reference?
It is a reference HMRC returns when you check a VAT number and give your own VAT number as the requester. You can keep it as proof that you made the check.
Related integrations
Let your AI work in HMRC Check a UK VAT Number today.
Start free. Your key stays encrypted, and you decide what the AI may do.
Connect HMRC Check a UK VAT Number freePipMCP is not affiliated with HMRC Check a UK VAT Number. Product names are trademarks of their owners.