Tax diversification is the strategy of spreading your savings across Traditional, Roth, and taxable accounts so you can better control how and when you pay taxes in retirement. By giving yourself multiple “tax buckets” to draw from, you can smooth out taxes over your lifetime, avoid costly surprises like RMD spikes or IRMAA surcharges, and create more flexibility for strategic withdrawals or Roth conversions. It’s not about predicting future tax law — it’s about preparing for it.