Can I claim tax back for work expenses??

[simons123]

Sorry if this is a stupid question but generally had no idea until someone mentioned this today. I get 20p per mile I commute to work from my company but apparently can claim the tax difference between that and 45p a mile and I get that back in return? Also told I can claim a tax refund for things such as expenses on work clothes, food, etc.

Is this the case? If so am I better getting an accountant or is this simple to do myself??