The tax office doesn't allow you to claim mileage for your commute to your permanent place of work. So commuting to a regular office doesn't count. My official place of work is my home, so all commutes to all our offices count as business travel. If my company decided I should be office based, I would have to treat my travel to my local office as a commute, not work travel. I have a company car, but if I use my cycle to go to the local office, I get nothing from the company, even though I am saving them money, but I could claim the allowance on my tax return at 20p per mile to offset my tax liability (well, offset it a tiny amount anyway!) I think if you do 100 miles a week business travel on a bicycle, and don't get any payment from your employer (so claim the full 20p per mile from the tax office) you would get around £4 a week if you pay basic tax, and £8 on the higher rate.