From MDM the order this needs to be pinned somewhere
Current 10-year Treasury note yield is ~2%. See
http://quotes.wsj.com/bond/BX/TMUBMUSD10Y WHAT
0. Establish an emergency fund to your satisfaction
1. Contribute to 401k up to any company match
2. Pay off any debts with interest rates ~5% or more above the 10-year Treasury note yield.
3. Max HSA
4. Max Traditional IRA or Roth (or backdoor Roth) based on income level
5. Max 401k (if 401k fees are lower than available in an IRA, or if you need the 401k deduction to be eligible for a tIRA, swap #4 and #5)
6. Fund mega backdoor Roth if applicable
7. Pay off any debts with interest rates ~3% or more above the 10-year Treasury note yield.
8. Invest in a taxable account with any extra.
WHY
0. Give yourself at least enough buffer to avoid worries about bouncing checks
1. Company match rates are likely the highest percent return you can get on your money
2. When the guaranteed return is this high, take it.
3. HSA funds are totally tax free when used for medical expenses, making the HSA better than either traditional or Roth IRAs.
4. Rule of thumb: traditional if current marginal rate is 25% or higher; Roth if 10% or lower; flip a coin in between (or see
http://forum.mrmoneymustache.com/investor-alley/deciding-between-roth-and-traditional-ira-based-on-marginal-tax-rate/ if you want even more details on that topic). See also
https://www.bogleheads.org/forum/viewtopic.php?f=2&t=182081,
http://forum.mrmoneymustache.com/ask-a-mustachian/case-study-overwhelming-student-loan-debt-how-would-you-get-started/msg868845/#msg868845 and other posts in that thread about exceptions to the rule.
5. See #4 for choice of traditional or Roth for 401k
6. Applicability depends on the rules for the specific 401k
7. Again, take the risk-free return if high enough
8. Because earnings, even if taxed, are beneficial
529s would be last IMO.