This is defined by HMRC as:
“A workplace is a temporary workplace if an employee goes there only to perform a task of limited duration or for a temporary purpose. So even where an employee attends a workplace regularly, it will be a temporary workplace and so not a permanent workplace, if the employee attends for the purpose of performing a task of limited duration or other temporary purpose.”
As a contractor you will work on different assignments in different locations for a limited duration in each case but in order for HMRC requirements to be met they will need to be linked under a single employment. The Umbrella Company is your employer and you will work, as a permanent employee, under an overarching Contract of Employment.
However, if you intend only to work on a single assignment whilst in your employment with the umbrella company then your workplace automatically becomes permanent and the cost of travel is therefore not an allowable expense.
Expense claims for travel are also subject to the ’24 month rule’ which prevents a workplace from being a temporary workplace where an employee attends it in the course of a period of continuous work that lasts, or is likely to last, more than 24 months.