If possible, send actual electronic editable tax return that you submitted with your tax return. If you don’t have that available, email PDF copies of each tax return.
Each years tax return should be submitted in one PDF. For example, 2020 tax return should be one PDF file, 2019 tax return should be one PDF file, and so on.
Only Federal tax returns are needed NOT State.
If you submitted your personal and business taxes together make sure you include ALL Federal Schedules (Schedule E).
If you filed your business tax returns separately from personal make sure and include all applicable forms. (i.e. 1065, 1120s, k-1)