How to track historical contribution basis when rolling over a Roth 401k
Uncertainty about historical contribution basis makes it difficult to figure out how to sum up past contributions across accounts or determine tax implications when rolling over or withdrawing early. Without clear records, people are left guessing whether methods like summing W2 box 12 code AA values are reliable, or how the five-year rule and age 59.5 thresholds apply to their withdrawals.
What people tried
Every workaround mentioned in the threads below. We haven’t tested any of them — and nobody here is claiming they worked.
- 1Summing historical W-2 box values or 1099-R forms
- 2Relying on plan trustee statements upon rollover
- 3Leaving the money in the account to continue growing tax-free
- 4Withdrawing from other taxable or tax-deferred sources first
- 5converting up to the 12% bracket over time
- 6researching optimal Roth conversion strategies
In their words
Unedited, most upvoted first, each linked to the thread it came from.
“Could you help clarifying the tax implication for taking out from Roth at age 59 1/2?”source ↗
“I am a little fuzzy on the 5 year rule. Does 2k gain from last year's contribution get taxed?”source ↗
“Based on my account composition and RETIRED status - would I be subjected to the pro rata rule?”source ↗
“Once I quit/retire and roll my Roth 401k funds into a Roth IRA, am I able to withdraw my contributions tax/penalty free prior to age 59.5? Does it work like Roth IRA contributions at that point?”source ↗
“For determining contributions, can I sum my W2, box 12, code AA values over the years I've contributed? Is that an unambitious and reliable method to ascertain contributions or am I missing something?”source ↗
“It's too late for me to "clean it up" as I am no longer working? Do I have the option to rollover my Rollover IRA back into the trad 401k that I am still maintaining?”source ↗
Where this came up
People with this problem also raised
- 2How to hit max 401k contribution with whole percentage limits
- 4Should I max my IRA or 401k first after a raise?
- 3How to handle 401(k) contributions and employer matches when changing jobs
- 5What do I do with an inherited IRA?
- 2Employer messed up my 401k start date and lost match
- 2Why are my account balance and vested balance the same?