Missed expenses for 2020

[crs5]

If I did not claim the expenses on my 2020 taxes, can I claim them on the 2021 taxes?  Is there a special form I need to complete.

Also, can I claim the room I used for my business along with the internet, electricity, etc.

[Donna F 77]

If you didn't report your self employment expenses on your 2020 tax return, you would need to amend your 2020 tax return to include those expenses.  You are not allowed to report expenses that were paid in 2020 on your 2021 tax return. 

You may be able to claim a Business Use of Home on Form 8829 for the room you used for your business.  There are two methods to determine the expense -- simplified and actual expense.  Here are some links with details on how to calculate the expense:

Home Office Deduction 

IRS Business Use of Home