How does the 5 year hold for ROTH conversions work with previous ROTH investments?

[RetireSoon]

I have existing ROTH accounts with 2 different firms. I'd like to do a 403b to ROTH conversion of about half of my 403b funds between retirement and age 70. How do I avoid locking up my previous ROTH investments? Can I just open a new account at a different firm, and not mingle old and new ROTH money?

[Bsch4477]

The 5 year rule applies to your first Roth opening. The clock is not reset for subsequent Roths. 

[Opus 17]

First, all Roth IRA's are treated as a single individual retirement arrangement, for all purposes including withdrawals, so opening a new account won't change any issue you might think you have.

Then, as long as you have satisfied the general 5 year clock with any Roth IRA, that clock is satisfied for all Roth IRAs.

There is a separate 5 year clock on conversions -- if you convert money now, and withdraw it in less than 5 years, you would owe a 10% penalty, but only if you are under age 59-1/2.  If that is true, we can discuss how withdrawals are attributed to contributions and conversions and how the 5 year conversion clock works.  But if you are over 59-1/2 or will be over 59-1/2 when you want to make a withdrawal, all your Roth IRA withdrawal will be non-taxable and free from penalties, regardless of the 5 year conversion clock.