In general, an ''agency worker'' as defined by HMRC won't usually qualify for tax refunds for thinks like travel to their workplaces.  However, it all comes down to what being an ''agency worker'' really means.

The taxman has very specific definitions he uses for terms like this, and they don't always line up with the normal people talk.  For example, simply getting a job from an employment agency, doesn't make you an ''agency worker'' in their eyes, even though that's  how you might describe your work situation to friends and family.  An agency supplies workers to the ''end user'' i.e the company that the work is actually being carried out for.