HMRC offers a helpful online tool that allows agents and taxpayers to check when they can expect a response to a query or request that they have made. The online tool is updated weekly with the latest information.

The full list of taxes the tool can currently be used for are as follows:

• Child Benefit
• Corporation Tax
• Construction Industry Scheme (CIS)
• Employers’ PAYE
• Income Tax
• National Insurance
• Self-assessment
• Tax credits
• VAT

Agents can also check how long it will take HMRC to:

• register you as an agent to use HMRC online services;
• process an application for authority to act on behalf of a client; and
• amend your agent details.

The online tool can be accessed at the following address, and you do not have to be logged in to receive an answer: https://www.tax.service.gov.uk/guidance/Check-when-you-can-expect-a-reply-from-HMRC/start/are-you-an-agent.