The employees are required to buy equipment to use as part of their employment may be able to claim tax relief based on the cost of the equipment acquired. In most cases you can claim tax relief on the full cost of this type of equipment as it usually qualifies for a type of the Capital Allowance called annual investment allowance. Any tax relief would be reduced if the employer provides a contribution towards buying the item.

The way to claim tax relief depends on the amount you’re claiming. HMRC provides the following information on making a claim:

Claims up to £2,500

You should make your claim:

• using a Self-Assessment tax return if you already fill one in
• online or by printing and posting form P87 if you don’t already fill in a tax return 
• by phone if you’ve had a successful claim in a previous year and your expenses are less than £1,000 (or £2,500 for professional fees and subscriptions)

Claims over £2,500

• You can only claim using a Self-Assessment tax return. You will need to register if you don’t already complete a return.

There are different rules for employees who use their own uniforms, work clothing, and tools for work. It is possible to claim for the cost of repairing or replacing small tools you need to do your job (for example, scissors or an electric drill), or cleaning, repairing or replacing the specialist clothing (for example, a uniform or safety boots). A claim for valid purchases can be made against receipts or as a ‘flat rate deduction’. However, an employee cannot claim relief on the initial cost of buying small tools or clothing for the work.

‘Tax relief’ means that you either:

• payless tax to take account of the money you’ve spent on specific things, like business expenses if you’re self-employed
• get tax back or get it repaid in another way, like into a personal pension

https://www.gov.uk/tax-rel-for-employees/working-at-home