TLH and Portfolio Construction

Tax-loss harvesting should not be an afterthought; it should be baked into your portfolio design from the start. When you construct a portfolio intended for harvesting, you make different choices about which funds to hold and how to structure your accounts. You identify substitute pairs before you need them, align your rebalancing process with harvesting opportunities, and ensure that your substitutes remain in your portfolio long enough to be worthwhile. A harvest-ready portfolio is more organized, more tax-efficient, and less prone to mistakes.

Key takeaways

• Design your portfolio around harvest-ready fund families, not random selections.
• Pre-identify all substitute pairs and document them before the tax year begins.
• Use the same asset-class funds consistently across taxable and tax-deferred accounts for simplicity.
• Plan rebalancing windows to create harvesting opportunities without disrupting allocations.
• Monitor your current gains and losses throughout the year so you harvest at the right moment.

The harvest-ready portfolio structure

A harvest-ready portfolio has the following characteristics:

1. Predictable fund selection. You use the same few funds repeatedly, such as VTI, BND, VXUS, and VWRL (or your local equivalent). This limits the number of possible losses you might encounter and makes tracking much simpler.

2. Documented substitutes. You have a written (or digital) record of which fund you will buy if a particular holding falls into a loss. For example: VTI → ITOT or SCHB. BND → AGG. VXUS → IEFA.

3. No performance chasing. You do not abandon funds because of short-term underperformance. Frequent swaps create wash-sale risks and fragment your holdings. Stick with your chosen funds unless there is a structural reason to change (e.g., a fund closes or its expense ratio becomes uncompetitive).

4. Aligned accounts. Your taxable account, IRA, and 401(k) hold the same asset-class funds. This makes rebalancing seamless and prevents mistakes like accidentally selling a tax-deferred holding and buying its substitute in the taxable account.

5. Integrated rebalancing. Your annual (or quarterly) rebalancing process doubles as a harvesting checkpoint. When you rebalance, you review losses and harvest them if tax-efficient.

Example: a three-fund harvest-ready portfolio

Suppose you are building a simple three-fund portfolio with 50% stocks, 30% international, 20% bonds:

Taxable brokerage account:

• VTI (50% of portfolio) — US total stock
• VXUS (30% of portfolio) — International developed markets
• BND (20% of portfolio) — Bonds

Identified substitutes (should any holding fall into a loss):

• VTI → ITOT or SCHB
• VXUS → IEFA
• BND → AGG or SCHZ

Tax-deferred accounts (401(k), IRA, etc.):

• VTI (50%) — same as taxable
• VXUS (30%) — same as taxable
• BND (20%) — same as taxable

With this structure, if VTI drops by 20% in a down market and you also realize other gains (from rebalancing or from a job bonus), you can harvest the VTI loss by swapping into ITOT, maintaining your allocation while capturing the tax benefit. Your 401(k) still holds VTI; no wash-sale risk there.

Integrating harvesting into rebalancing

Rebalancing is the ideal moment to harvest. Here's a tactical sequence:

1. Quarterly or annually, review your allocation. If you are 52% stocks instead of 50%, rebalance.

2. Identify losers. During rebalancing, check which funds are below cost basis. Is there a loss available to harvest?

3. If losses are available and you have gains to offset, harvest strategically. Sell the loser (now below cost basis), buy the substitute, and complete your rebalancing in one move.

4. If losses exceed gains, defer the harvest to a future year when you have gains to offset, or use the $3,000 annual ordinary-income deduction.

5. On day 31 (or day 61 in the US), return to your original fund if desired. After the wash-sale window closes, you can sell the substitute and repurchase the original fund if you prefer, or keep the substitute if it has performed well or if the tax cost of reverting is high.

This integrated approach makes harvesting automatic and reduces the temptation to chase performance or ignore losses.

Managing multiple accounts and wash-sale risk

If you hold the same fund in multiple accounts (taxable, IRA, 401(k)), you must be careful not to trigger a wash sale inadvertently. Here's the risk scenario:

1. You sell VTI at a loss in your taxable account on September 1.
2. You forget that you also hold VTI in your 401(k).
3. On September 15, your 401(k) rebalances or receives a contribution, and you automatically (or manually) buy more VTI via the 401(k)'s investment menu.
4. The IRS sees two buys of VTI within 30 days of the taxable-account loss and disallows the loss.

To prevent this, synchronize your account activities. When you harvest a loss in the taxable account, pause contributions or rebalancing in the other accounts for 31 days, or make sure those accounts are not acquiring the same fund during the window.

Some investors maintain different funds in each account specifically to avoid this risk. For instance:

• Taxable: VTI, VXUS, BND
• 401(k): ITOT, IEFA, AGG

This segregation eliminates wash-sale risk from cross-account trades. The trade-off is less transparency and more complexity.

Seasonal patterns and harvesting windows

In practice, harvesting opportunities cluster in late summer and autumn. After a strong first half (especially in 2020 and 2021), markets often pullback in September or October, creating losses on holdings that rose earlier in the year. Tax-aware investors typically harvest in October and November to capture these losses before year-end.

Plan your portfolio with seasonal dynamics in mind. If you know markets historically correct in Q3, prepare your substitutes in Q2 so you are ready to act if losses appear.

Portfolio design flowchart

Related concepts

• Substitute Funds for TLH
• Why We Rebalance

Next

Not every investor should harvest losses. Some portfolios are too small, some investors are in low tax brackets, and some accounts are entirely tax-deferred. Understanding when TLH is worthless is as important as knowing when it is valuable. We turn to the conditions under which harvesting is not worth the complexity.