The law requires your employer to reimburse reasonable expenses necessarily incurred in the course of your employment. Your contract of employment may contain express terms specifying what expenses are to be reimbursed and in what circumstances, for example:
It is essential that you get receipts for reimbursable expenses. Most employers will set out an expenses policy, with rules and procedures for claiming expenses.
Even if there is no express term in your contract, the law still entitles you to be reimbursed. However, this can be difficult to pursue in the case of a dispute, so it is better for all concerned to have a clearly stated expenses policy.
Some expenses paid by the employer may be taxable.