Let’s say you have a 401(k) plan worth $200,000 and you and your spouse have $200,000 in equity in the family home.  Should you trade your spouse the house for your pension plan?

No because the equity in the house is tax free.  You will pay a tax of about 35% when you start taking your pension.  That makes the pension worth 65% of $200,000 or $130,000.

Would you let your spouse keep $10,000 in the joint checking account if you can keep $10,000 in joint IBM stock?  The bank account is tax free.  Any capital gains on the IBM stock will be taxed when you sell it.  So you won’t get $10,000 in cash.

Trades that look equal on paper, aren’t necessarily equal once you take taxes into account.