TDA and TT collaborate to import tax data from a TDA account to Turbo Tax. That works great. The question is what happens if you have import data from two accounts?

To import multiple brokerage accounts from one broker, please see the instructions provided by CatinaT1 here. 

Please also see the below TurboTax Help Article for information on stock transactions in TurboTax Online.

How many stock transactions can TurboTax Online handle?

Thank you.

I had not thought about that.

I do not fully understand the use of cookies.

I will not know how it works until TD Ameritrade announces the tax report are ready and try it.

If I understand the outlined steps

Import the first account data

With TT and TDA still open, find away to delete all the TDA cookies

Then import the second account tax data in the same manner.

Is this correct?

Since tax software accesses the TD Ameritrade 1099 by the TD Document ID, you should have no problem no matter how many accounts you have.

BUT

if you have thousands of trades, you need the summary option.

TurboTax can't import thousands of trades.