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HMRC internal manual

Employment Income Manual

Travel expenses: general: choice of route: costs incurred in error: example

An employee has to travel by train on business from the south of England to Scotland. By mistake she travels up the West Coast although her ticket is only valid for the East Coast route. As a result she has to buy another ticket and so incurs substantial extra cost. She can deduct this extra cost as part of the cost of her business travel.