How do I know the value of the land of my home for calculating the home office deduction?

Enter the value of the land when you began to use your home office or part of your home for business purposes. If you used your home for business right after you bought the home, then the land value might be on the home purchase documents. A property tax statement or mortgage appraisal around the time you began using your home for business will also have a land value on it.

If you don't have any of those documents, just enter a reasonable amount for the value of the land. A reasonable amount is what you think it would have cost to buy the land on the date that you began to use your home for business.