Buy a low cost diversified ETF. Take all your options, sort on management expense, and read the description. Not sure about your personal preferences and needs, but you're still young so you can be relatively risky. Buy 75% of the cheapest diversified stock fund and 25% of the cheapest diversified bond fund.
It doesn't have to be too complicated. You just have to not make very bad decisions (all stocks a year before retirement, or all cash for decades). And avoid high fees
In the US, Roth contributions are made with "after-tax dollars", while 401K contributions are generally made with "pre-tax dollars", so if you rollover the 401K into a Roth, the IRS will see the rollover (aka "conversion") as a bump in your income and ask you to pay tax on the rollover amount, with the remainder/net going to the Roth IRA.
I still think a Roth conversion is a good idea for self-directed investments, but folks should be aware of the incoming tax bill.
[1] https://www.investopedia.com/articles/retirement/09/roth-401...
My tax rate will be higher while I'm working and earning a salary than they will when I'm retired.
Also, by keeping the base amount higher (pre tax), won't I have more growth than compared to the after-tax amount?
If you didn't work the entire year or your income was otherwise variable (bonuses or whatever other reason) then it makes more sense than usual to do roth contributions, or rollovers/recharacterization from traditional to roth, in lower-income years. Assuming you can afford to, and want to maximize what you put into tax-advantaged accounts.
The annual contribution limits are also on dollar amount that goes into the account, so if you're maxing out then you can get more out of a roth ira/401k overall. Not all companies offer the choice of roth on their 401k plans, which is a little annoying.
A robo-advisor is a tech company in the financial space. They provide one-size-fits-all opinionated investment strategy (ie they do not let you pick individual stocks etc, you respect their overall portfolio strategy) that is not actively managed (ie they buy "the market" instead of individual stocks). As a result you will be diversified and you pay extremely low fees (many company 401k plan funds have horrible fees that completely take advantage of you).
Personally, I use betterment (https://www.betterment.com/). I approve of their investment portfolio strategy (https://www.betterment.com/portfolio/) and their fees are significantly below the fund choices I have in my company's 401k, so it is a good fit for me.
The one decision betterment does allow you to make (again the goal is simplicity), is your stock/bond allocation. Allocation strategy is a bit outside of the scope of this response, but to keep things simple I'll say anything from 70% stocks/30% bonds to 80/20 stocks/bonds is probably fine.
If you have further questions, or want a more "complicated" answer, feel free to email me directly (check my profile page). I'm an engineer, not a financial adviser, but I've been actively interested in personal finance for a long time now.
Another trick you can use is switch to a Roth 401(k). It means you'll be taxed on your savings today, but when you retire they'll be tax free. Now this is total speculation here, but I'm kind of assuming taxes will be pretty high in the coming decades as we try to keep social security going and pay down deficit spending, not too mention dealing with climate change fallout.
Also good for you on keeping all your money in the 401(k) accounts, some people cash them out when they change jobs which triggers penalities and taxes. If you can however, I would roll all your accounts in to one giant 401(k) so you can better keep track of what's going on.
There are several "timelimit" related aspects to 401k rollovers, neither would apply in your circumstance. You sound anxiety paralyzed like you made some "unfix-able past mistake" and there is zero reason for you to be.
> It is just sad :(
See my other comment about consolidating all of your legacy 401ks into a single robo-advisor (betterment/wealthfront/etc). It isn't hard, mainly consists of sending a few emails to HR departments and forwarding a few paper checks. Any robo-advisor will have a support team that will hold your hand through the process for free - they want to earn your business.
Step 2: ???
Step 3: Profit!
Seriously though, everyone has given very solid advice. As mentioned, the first thing you should do is consolidate all 401K accounts into a single IRA (or Roth IRA if you're hedging against much higher tax rates in the future).
Also, consider setting aside 10% of your IRA to play/learn/speculate with. By this I mean investing in funds or direct stocks in areas that you have an outside interest in (e.g. tech, clean energy, socially responsible, geographic region, etc). Due to your interests in this area outside of pure personal finance, you may be motivated to learn more about investing in general - which is always a good thing and will be more important as you begin to pull money out of your IRA during retirement.