If I have a joint Vanguard mutual funds account with my mom and I file separately, do we both have to file the 1099-DIV information and the Capital Gains and Losses?

The key is the social security number assigned to the account, which is where the IRS will be looking for the income.

 

It should be reported on that tax return or you can choose to nominee the portion that would be reported by the other person by using the nominee procedures below.

 

Nominee returns. Generally, if you receive a Form 1099 for amounts that actually belong to another person or entity, you are considered a nominee recipient. You must file a Form 1099 with the IRS (the same type of Form 1099 you received).  You must also furnish a Form 1099 to each of the other owners. File the new Form 1099 with Form 1096 (this is a transmittal for the 1099) by mailing to the Internal Revenue Service Center for your area.

• On each new Form 1099, list yourself as the payer and the other owner, as the recipient. On Form 1096, list yourself as the nominee filer, not the original payer.  The nominee is responsible for filing the subsequent Forms 1099 to show the amount allocable to each owner.

This question was previously answered by DianeW