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    Portfolio Rebalancing

    6 min readUpdated June 2026

    Educational content only. This article is for informational purposes and does not constitute personalized financial, tax, or investment advice. Consult a qualified professional for guidance specific to your situation.

    TL;DR

    • Rebalance when you've drifted 5+ percentage points from your target, or annually at minimum
    • In tax-advantaged accounts, sell freely: No capital gains tax in a 401(k) or IRA, so rebalancing is free
    • In taxable accounts, use new contributions first: Direct new money to underweight assets before selling anything
    • Target-date funds rebalance themselves: If you hold one, you don't need to do anything

    Not sure if your current allocation is still right for your situation? Book a free 15-min call and I can review your portfolio.

    When you set up a portfolio, you choose a target allocation — say, 80% stocks and 20% bonds. Over time, markets move, and your actual allocation drifts away from that target. Rebalancing is the process of restoring your portfolio to its intended mix.

    It's not exciting. It's not a way to boost returns. It's a risk management practice — and for most investors, it needs to happen only once or twice per year.

    Why Drift Happens and Why It Matters

    Suppose you start with an 80/20 stock/bond split. Stocks have a good year and return 20%, while bonds return 5%. After one year, your portfolio is now roughly 83% stocks and 17% bonds — even though you didn't change anything. After a strong multi-year bull market, you could be holding 90%+ in stocks without realizing it.

    StartingAfter 1 YearAfter 5 Years
    Stocks (7%/yr)$80,000 (80%)$85,600 (82%)$112,293 (86%)
    Bonds (3%/yr)$20,000 (20%)$20,600 (18%)$23,185 (14%)
    Total$100,000$106,200$135,478

    Without rebalancing, a 5-year bull market quietly converts an 80/20 portfolio into an 86/14 portfolio — meaningfully more stock risk than you originally chose. When the correction eventually comes, your losses will be larger than you planned for.

    How Often Should You Rebalance?

    Research suggests two workable approaches, and they both arrive at a similar answer: infrequently.

    Calendar-Based

    Rebalance on a fixed schedule — once or twice a year, regardless of how much things have moved.

    Best for: Simplicity. January and July, done.

    Threshold-Based

    Rebalance when any asset class drifts more than 5 percentage points from its target. Otherwise, do nothing.

    Best for: Minimizing unnecessary trading. Often results in fewer rebalances than calendar-based.

    Most financial research finds that rebalancing more than once or twice per year doesn't improve outcomes meaningfully — and generates unnecessary transaction costs and taxes. Quarterly or monthly rebalancing is overkill for a long-term passive investor.

    How to Actually Rebalance: 3 Methods

    There's a tax-efficient order of operations here. Try each method in sequence before moving to the next.

    1

    Direct New Contributions

    When you make your next investment, put 100% of it into your underweight asset. If stocks have grown from 80% to 85%, invest your next $500 entirely into bonds. This rebalances without selling anything — no taxes, no transaction costs.

    Best if: Your drift is small and you're still actively contributing.

    2

    Sell and Buy in Tax-Advantaged Accounts

    In a 401(k), IRA, or HSA, you can sell overweight assets and buy underweight ones with zero tax consequence. There are no capital gains taxes in these accounts. This is the cleanest rebalancing method and should be used before touching taxable accounts.

    Best if: You have meaningful drift and hold the overweight asset in a retirement account.

    3

    Sell in Taxable Accounts (Last Resort)

    If methods 1 and 2 aren't enough — or your overweight asset is only in a taxable account — you'll need to sell and pay capital gains tax. Prioritize selling assets held longer than 1 year (long-term capital gains rates are lower) and consider tax-loss harvesting opportunities at the same time.

    Best if: You've exhausted the first two methods or the overweight position is only in taxable.

    If You Hold a Target-Date Fund, Stop Here

    Target-date funds (like Fidelity Freedom 2055 or Vanguard Target Retirement 2055) automatically rebalance internally. You do not need to do anything. This is one of the biggest advantages of target-date funds in 401(k)s and IRAs — rebalancing is baked in at no extra cost. See the retirement investing guide for more on target-date fund selection.

    Tax Implications of Rebalancing

    Tax-Advantaged Accounts

    Sell and buy freely. No capital gains taxes. No wash-sale concerns. You can rebalance as often as needed with no tax cost. This should be your first choice for any rebalancing trades.

    Taxable Accounts

    Selling at a gain triggers capital gains tax. Short-term gains (held <1 year) are taxed as ordinary income. Long-term gains (held >1 year) get preferential rates. Before selling, calculate whether the tax cost outweighs the rebalancing benefit.

    This is why asset location matters: holding bonds (which need to be rebalanced most often) in tax-advantaged accounts lets you rebalance without triggering gains. See the tax-loss harvesting guide for how to offset gains when you do need to sell in a taxable account.

    Annual Rebalancing Checklist

    • Check your current allocation vs. your target. If no asset class has drifted more than 5 percentage points, you likely don't need to do anything.
    • If rebalancing is needed, start with Method 1: direct your next contribution entirely to the underweight asset.
    • If that's not enough, sell in your IRA or 401(k) where there's no tax cost.
    • Only sell in taxable accounts as a last resort, and prefer assets held more than a year (lower tax rate).
    • If you hold only target-date funds, close this tab — you're already done.

    Not sure if your current allocation still matches your goals?

    As markets move and life changes, your target allocation may need to shift — not just be restored. I can review your portfolio and help you decide if a rebalance or a re-allocation is what you actually need. One-time consultation, no ongoing fees.

    Book a Free 15-Min Call