Home office expenses were disallowed in 2017 under TCJA. If you are both self-employed, you each have to have your own separate office space. You can't share the same space. You would create a separate home office for your spouse in the same manner that you do your own.
Shared use.
If you share your home with someone else who uses the home to conduct business that also qualifies for this deduction, you may not include the same square feet to figure your deduction as the other person. You must allocate the shared space between you and the other person in a reasonable manner.
Exclusive Use
To qualify under the exclusive use test, you must use a specific area of your home only for your trade or business. The area used for business can be a room or other separately identifiable space. The space does not need to be marked off by a permanent partition.
You do not meet the requirements of the exclusive use test if you use the area in question both for business and for personal purposes.
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