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Thank you for your question..
Please advise if all mileage stated was business use. If not, what was business mileage?
Sarah, thank you for your prompt reply.
You can claim mileage allowance for business miles stated in your question. First 10,000 miles at 45p per mile and each mile over this number at 25p per mile.
When you complete employment section of your tax return report mileage claim in box 17 - business travel and subsistence. A copy of SA102 can be viewed here
I hope this is helpful and answers your question.
If you have any other questions, please ask me before you rate my service – I’ll be happy to respond.
Thank you for your reply.
Your claim is for some £5,077 (12,306 miles).
Form P87 is used if your claim for allowable expenses is for £2,500 or less.
More information on this can be found here