What Rebalancing Actually Means
When you set up a portfolio, you choose a target allocation — say, 70% stocks and 30% bonds — based on your goals, time horizon, and comfort with risk. But markets don't stand still. If stocks outperform bonds for a year or two, that 70/30 split might quietly become 80/20 or higher. Your portfolio now carries more risk than you originally intended, without you making a single deliberate decision.
Rebalancing is the process of selling assets that have grown above their target weight and buying assets that have fallen below it — restoring your portfolio to its intended allocation. It's a maintenance task, not a market-timing move. As discussed in our framework for long-term asset allocation, your target mix should reflect where you are in life, not where the market is today.
Rebalancing Is a Discipline, Not a Prediction
The point of rebalancing is not to predict which asset class will outperform next. It's to maintain a consistent risk profile aligned with your goals. Investors who stay disciplined about rebalancing tend to avoid the behavioral trap of letting winning positions grow unchecked — which often leads to larger losses when those positions eventually correct.
When to Rebalance: Two Practical Approaches
There's no single correct rebalancing schedule, but two approaches have broad support among financial researchers:
- Calendar-based: Review and rebalance at fixed intervals — annually or semi-annually. This is simple to stick to and prevents you from reacting to short-term volatility.
- Threshold-based: Rebalance when any asset class drifts more than a set percentage — commonly 5 percentage points — from its target. For example, if your target stock allocation is 70% and it rises to 76%, that triggers a review. This approach is more responsive to actual market movement.
Many investors combine both: review annually, but rebalance only if drift exceeds a threshold. This reduces unnecessary trading while keeping your allocation within a reasonable band. One common pitfall is rebalancing too often — excessive activity can generate transaction costs and, in taxable accounts, capital gains taxes that quietly chip away at returns. For more on habits that undermine long-term results, see early investing errors that quietly undermine long-term returns.
Avoid Rebalancing as a Reaction to Headlines
Market volatility often triggers the urge to act. Rebalancing in response to fear or excitement — rather than a predetermined rule — is a form of emotional investing. Set your trigger criteria in advance and stick to them, regardless of what financial news is dominating the moment.
How to Rebalance: Step-by-Step
The mechanics of rebalancing are straightforward once you understand your current vs. target allocation. Use the steps below as a repeatable process. If you're still building out your investment approach as a younger professional, our article on investing in your twenties and thirties provides helpful context on how your strategy may need to evolve.
Record your current portfolio value and allocation
Log in to all accounts where you hold investments — 401(k), IRA, brokerage, and any other accounts — and note the current market value of each asset class. Calculate each as a percentage of your total portfolio. This gives you a clear picture of where you stand before you make any changes.
Compare current allocation to your target
Subtract your current allocation percentage from your target for each asset class. A positive gap means the asset is underweight; a negative gap means it's overweight. This comparison tells you exactly where drift has occurred and in which direction.
Determine whether rebalancing is warranted
Apply your chosen threshold — if no asset class has drifted beyond your trigger point (e.g., 5 percentage points), you may not need to act yet. If you're on a calendar schedule, proceed regardless of drift size. Document your decision either way so your reasoning is clear at the next review.
Prioritize rebalancing in tax-advantaged accounts
In a 401(k) or IRA, selling overweight assets and buying underweight ones has no immediate tax consequence. This makes these accounts the most efficient starting point. In taxable brokerage accounts, selling appreciated assets triggers capital gains taxes, so consider whether you can achieve the needed rebalancing through tax-advantaged accounts alone before acting in taxable ones.
Use new contributions to rebalance before selling
Before executing any trades, check whether directing upcoming contributions — paycheck deferrals, IRA contributions, or dividend reinvestments — toward underweight asset classes can close the gap. This approach avoids selling altogether and is especially effective for investors who are still in an active savings phase.
Execute the necessary trades
Once you've used contributions where possible, execute any remaining trades needed to restore your target allocation. Sell the overweight positions first, then use the proceeds to purchase underweight assets. Keep transaction costs in mind — some funds carry redemption fees, and frequent trading in certain accounts may trigger restrictions.
Document the rebalance and set your next review date
Record the date, the trades executed, the pre- and post-rebalance allocation, and any tax-related notes (e.g., realized gains or losses). Set a calendar reminder for your next review. Consistent documentation makes it easier to track your discipline over time and simplifies tax filing if gains or losses were realized.
This article is for general informational and educational purposes only and does not constitute personalized investment, tax, or financial advice. Rebalancing decisions depend on your individual circumstances. Consult a licensed financial advisor or tax professional before making changes to your portfolio.
