Portfolio Rebalance Calculator

Portfolio rebalancing brings your asset mix back to target weights after market moves drift allocations off plan. If stocks rally and bonds lag, you may end up with more equity risk than intended. Rebalancing means selling overweight assets and buying underweight ones — or directing new contributions to lagging categories — to restore your policy mix.

Investors often rebalance annually or when any asset class drifts more than a set band (e.g., 5 percentage points). Rebalancing can enforce a buy-low, sell-high discipline but may trigger taxes in taxable accounts and transaction costs. Retirement accounts avoid capital gains on trades within the account.

Example: a $100,000 portfolio targets 60% stocks ($60,000) and 40% bonds ($40,000). After a rally, stocks are $68,000 and bonds $38,000 (64% / 36%). To rebalance without adding cash, sell about $4,000 of stocks and buy $2,000 of bonds. This tool shows buy/sell amounts from your inputs — it does not recommend a specific allocation.

Contribution-only rebalancing avoids selling in taxable accounts. Direct new deposits and dividends into underweight assets until weights realign — slower but often tax-efficient.

Threshold rebalancing (e.g., rebalance when any sleeve drifts 5+ points from target) trades less often than calendar rebalancing, reducing costs but allowing longer risk drift.

Risk tolerance sets targets, not this calculator. A 30-year-old and a retiree may choose different stock/bond targets — you enter the policy mix; the tool computes trades.

Worked example with three assets: $200,000 total, targets 50/30/20, current 55/25/20 after a stock rally. Stock sleeve is $10,000 overweight — sell stocks, buy bonds and alternatives to match targets.

International vs US, growth vs value, and factor tilts add sleeves. The same math applies — compare current dollar value in each bucket to target dollars.

Not investment advice. Appropriate allocation depends on goals, time horizon, and risk capacity — consider personalized guidance for major decisions.

Tax-loss harvesting pairs well with rebalancing in taxable accounts — sell losers to offset winners while restoring targets.

Glide paths in target-date funds shift allocation automatically — manual rebalancing is unnecessary inside those products.

Crypto and alternative sleeves add volatility — wider rebalance bands (7–10%) reduce trading in highly volatile assets.

Municipal bond and taxable bond sleeves belong in separate accounts when possible — hold tax-inefficient assets in tax-deferred accounts per asset location principles.

Rebalancing premium historically came from buying volatile assets when cheap — past premium is not guaranteed; bands still enforce discipline.

Cash drag from holding rebalance proceeds uninvested temporarily lowers returns — deploy proceeds promptly or use simultaneous swap trades where brokers support exchange.

Small accounts may rebalance with new cash only to avoid trading costs — sell trades on a $5,000 portfolio can cost more in commissions than drift justifies.

Target-date funds shift allocation automatically — if you hold one, manual rebalancing between stock and bond sleeves is redundant unless you also hold separate satellite positions.

Drift tolerance bands should reflect risk policy — aggressive growth portfolios sometimes allow 10% drift before trading while conservative income portfolios rebalance at 3% drift.

Document rebalance trades for taxable accounts — cost basis on newly purchased lots starts fresh on the rebalance date for future gain calculations.

Institutional portfolios sometimes use tolerance bands per asset class rather than full-portfolio drift — apply the same buy-sell math independently to each sleeve when policies differ by category.

ESG or exclusion screens can block buying certain sectors during rebalance — substitute compliant funds within the same asset class when direct index replication is unavailable.

Confirm trade minimums and lot sizes with your broker before executing small rebalance trades in taxable accounts.

Set calendar reminders for annual rebalance reviews even when drift bands have not triggered — policy discipline beats ad hoc timing.

Keep a written investment policy statement so rebalance targets stay consistent across years and account additions.