A HMRC tax investigation typically begins with a letter or phone call from the tax authority, informing the business or individual that they are under investigation.

The investigation can cover a range of tax-related issues, including income tax, corporation tax, VAT, and PAYE. The HRMC will request access to financial records and other relevant documents, and may conduct interviews with employees or other individuals connected to the business.

The investigation can take several months or even years to complete, depending on the complexity of the case. It is important to seek professional advice and support during this process to ensure that your rights are protected and that you are fully prepared for any potential outcomes.