Tax efficiency during the accumulation phase is the foundation of a tax-efficient retirement. The account types used to build wealth, the investments held in each account, the decisions about Roth versus traditional contributions, and the use of tax-loss harvesting in taxable accounts all have compounding effects that extend decades into retirement. Getting these decisions right during the working years creates flexibility and efficiency in retirement. Getting them wrong creates constraints and costs that are difficult to unwind.
The accumulation phase presents a specific set of tax planning opportunities that are most valuable when addressed consistently over time rather than reactively near retirement. Roth contributions in lower-income years, systematic tax-loss harvesting in taxable accounts, proper asset location across account types, and thoughtful contribution sequencing across account types all reduce the lifetime tax burden in ways that compound significantly over a thirty-year investment horizon.
This paper focuses on the tax planning decisions most consequential during the accumulation years, from the first 401(k) contribution through the final year of full-time employment. It addresses the Roth versus traditional contribution decision, account contribution sequencing, tax-loss harvesting, and the tax cost of high-turnover active management.
The Roth versus traditional contribution decision is fundamentally a tax rate arbitrage question. Traditional contributions reduce taxable income today, producing tax savings at your current marginal rate. Roth contributions are made with after-tax dollars but grow tax-free, with no tax at withdrawal. The financially superior choice depends on whether your current marginal rate is higher or lower than your expected marginal rate in retirement.
If you expect to be in a higher bracket in retirement, Roth contributions are advantageous: you pay tax now at the lower rate and avoid tax later at the higher rate. If you expect to be in a lower bracket in retirement, traditional contributions are advantageous: you defer tax to the period when rates are lower. If your rates are expected to be the same, the two options produce identical after-tax results in a simple model, though Roth has additional advantages from eliminating RMDs and providing more flexibility.
Roth contributions are generally superior in the early career years when income is low and marginal rates are modest. A worker in the 12% or 22% bracket has relatively cheap Roth dollars: paying tax now at 22% to avoid potential taxes at 32% or higher in retirement is a compelling trade. The Roth is also better when the account owner has a long time horizon for tax-free compounding, when they expect income to increase significantly over the career, or when they anticipate a large pre-tax balance that will generate significant RMDs.
The Roth also provides tax diversification value beyond the simple rate comparison. Having assets in Roth accounts in retirement gives the flexibility to manage taxable income by drawing from Roth in high-income years, staying below IRMAA thresholds, managing Social Security taxability, and providing tax-free inheritance to heirs.
Traditional contributions are generally superior when the current marginal rate is high and the expected retirement rate is significantly lower. A peak-earning professional in the 37% bracket who expects a much lower effective rate in retirement is getting a 37-cent deduction on every dollar of traditional contribution, and will likely pay much less than 37 cents in taxes on each dollar when withdrawn. For this person, the immediate tax deduction from traditional contributions is highly valuable.
For business owners who have flexible control over their taxable income, traditional contributions may also be preferable because they reduce the base for self-employment tax as well as income tax, providing a broader tax benefit than Roth contributions would.
When multiple retirement saving vehicles are available, the order of contributions has meaningful tax implications. The generally recommended priority sequence begins with capturing any available employer match in the 401(k), which is free money and represents an immediate 50% to 100% return on the matched amount. Second priority is maximizing contributions to an HSA if eligible, given the triple tax advantage. Third priority is maximizing IRA contributions, with the Roth or traditional choice depending on income and eligibility. Fourth priority is maximizing remaining 401(k) contributions beyond the match. Fifth priority is investing in taxable brokerage accounts.
This sequence is a starting point, not a rigid rule. The specific tax benefits of each account type, the employer match structure, the availability of Roth options in the 401(k), and the individual's current and expected tax situation all affect the optimal sequence. An advisor who knows the household's complete picture can refine this sequence for specific circumstances.
For workers who are uncertain about their future tax rate, splitting contributions between traditional and Roth, a strategy sometimes called tax diversification of contributions, creates optionality in retirement. A retiree with both traditional and Roth balances can draw from either source in any given year, managing taxable income with more precision than someone with assets in only one account type.
The tax diversification argument is strongest for middle-income earners whose retirement bracket is genuinely uncertain, those who expect significant variability in their retirement income needs, and those who want flexibility to manage IRMAA thresholds without eliminating the deduction benefit of traditional contributions entirely.
Tax-loss harvesting is the practice of selling investments in a taxable brokerage account that have declined in value to realize a capital loss, which can then be used to offset capital gains elsewhere in the portfolio or, if losses exceed gains, to reduce ordinary income by up to $3,000 per year. The loss is captured without necessarily changing the long-run investment exposure by replacing the sold position with a similar but not substantially identical investment.
The wash sale rule prohibits claiming a loss on a sale if the same or substantially identical security is repurchased within 30 days before or after the sale. The replacement investment must be similar enough to maintain the desired market exposure but different enough to avoid the wash sale rule. Common replacements include switching from one S&P 500 index fund to a total market index fund, or replacing a specific company stock with an ETF in the same sector.
The value of a harvested loss comes from the time value of the deferred tax. The loss doesn't permanently eliminate the tax, it defers it. When the replacement investment is eventually sold at a gain, the lower cost basis means a larger capital gain is recognized. The benefit is the deferral of the tax from the current year to a future year, with the time value of money working in the investor's favor.
The deferred tax benefit is most valuable for high-income investors with large taxable portfolios and a long time horizon before the replacement positions would need to be sold. It is less valuable for lower-income investors in the 0% capital gains bracket, who pay no tax on long-term gains anyway, and for investors who plan to leave the taxable account to heirs, who receive a step-up in basis that eliminates the deferred gain at death.
The mirror strategy, tax-gain harvesting, is selling appreciated positions in low-income years to realize capital gains at the 0% rate. Married couples filing jointly with taxable income below approximately $94,000 in 2024 pay no federal tax on long-term capital gains. A retiree or near-retiree in a low-income year, perhaps between employment and Social Security or in the early retirement years, can realize appreciated gains tax-free and reset the cost basis, eliminating the future tax liability on those gains.
Every time a mutual fund or ETF sells a holding at a gain, the gain is distributed to shareholders as a capital gains distribution. Shareholders who hold the fund in a taxable account receive a 1099 showing the taxable distribution even if they didn't sell any shares. High-turnover actively managed funds that trade frequently generate larger capital gains distributions, creating annual tax drag for taxable account holders that compounds over time.
Low-turnover index funds and ETFs typically generate minimal taxable distributions because they only sell holdings when the index changes its composition, which happens infrequently. An index fund can be held for decades in a taxable account with minimal annual tax drag from capital gains distributions, with the tax bill deferred until the fund itself is eventually sold.
Combining the expense ratio of actively managed funds with the annual tax drag from capital gains distributions and the transaction costs of higher turnover produces a total cost of active management in taxable accounts that exceeds the expense ratio alone. Morningstar research has documented that the after-tax return difference between low-cost index funds and average actively managed funds in taxable accounts is larger than the before-tax difference, because active management generates more taxable events.
The Roth versus traditional decision should be revisited each year as income changes, tax law changes, and retirement expectations evolve. A worker who takes a high-paying job at 45 might shift from Roth to traditional contributions. A worker who takes a career break or experiences a lower-income year might shift the other direction.
Review the taxable brokerage account at least annually, and more frequently during significant market declines, for harvesting opportunities. Set a threshold, such as a loss of 5% or more in a position, that triggers a review for harvesting. The discipline of systematic harvesting compounds over years into meaningful tax deferral.
Actively managed funds, taxable bonds, high-dividend stocks, and REITs belong in IRAs and 401(k) plans, not in taxable accounts. Index funds and ETFs held for long-term appreciation belong in taxable accounts where the long-term capital gains rate applies and where tax-loss harvesting is possible. This asset location discipline, maintained consistently through the accumulation years, creates a significant advantage in retirement.
The retirement calculator at plan.johnkoyle.com allows you to enter account balances across pre-tax, Roth, and taxable accounts separately. Running the Withdrawal Strategy analysis with different starting allocations across these account types shows how the contribution decisions made during accumulation affect the tax efficiency of the distribution phase in retirement.
This annual question ensures the contribution decision is being made with current information rather than out of habit.
This establishes whether tax-loss harvesting is a formal part of the portfolio management process.
This question addresses whether tax-inefficient assets are in the right account type.
This forward-looking question connects accumulation decisions to retirement income outcomes.
This scenario question quantifies the impact of a contribution strategy change and supports an informed decision.
The retirement planning calculator at plan.johnkoyle.com was built to model exactly the dynamics discussed in this paper. The Withdrawal Strategy tab in the retirement calculator at plan.johnkoyle.com shows how the mix of pre-tax, Roth, and taxable accounts at retirement affects the tax efficiency of the distribution phase. For workers still in accumulation, entering different hypothetical balances across the three account types shows how different contribution strategies during the working years produce different retirement income tax pictures. Use this tool to model the long-run impact of your current Roth versus traditional contribution split on your projected retirement tax burden.
John Koyle, AIF®, is the Co-Founder of Red Cedar Wealth Advisors, headquartered in Pocatello, Idaho. He holds the Accredited Investment Fiduciary (AIF®) designation, awarded by the Center for Fiduciary Studies (Fi360), which signifies completed coursework, a rigorous examination, and ongoing continuing education in fiduciary responsibility and prudent investment practices.
John serves individuals and families in or approaching retirement throughout eastern Idaho, the Pacific Northwest, and across the country via Zoom. Clients work directly with John, not a junior team. Red Cedar Wealth Advisors operates under Osaic Wealth, Inc. (Member FINRA/SIPC) and Osaic Advisory Services, LLC for investment advisory services.
Every client relationship is built on five integrated disciplines. The proportions shift with the client and the moment. The integration is constant. Most of the actual value sits in how these disciplines connect, not in any single one of them.
Retirement planning is a discipline that barely existed a generation ago. For most of modern history, people worked until they physically couldn't and then they died, usually fairly close together. The idea that an individual should spend decades saving, then spend decades drawing down those savings, with a plan that accounts for inflation, taxation, sequence risk, healthcare, longevity, and estate transfer, that's maybe forty years old.
Which means almost nobody your age grew up watching their parents do it properly. There's no cultural muscle memory. The advice industry backfilled that gap with rules of thumb that work sometimes and fail catastrophically the rest of the time. The 4% rule. 'You can take Social Security at 62.' 'Target-date funds will handle it.' These are not bad starting points. They are terrible ending points. Real planning is specific, personal, and built on principles that hold up across the full range of outcomes, not just the average one.
The tax code is a set of instructions Congress wrote to shape behavior. Aligning your financial life with those instructions is not aggressive planning. It is the planning. Roth conversion sequencing, capital gains compression on concentrated positions, charitable remainder trusts, Social Security timing, beneficiary coordination. None of these are obscure. They're all legitimate, all written into the code intentionally, and all under-used. Most CPAs handle compliance. The strategy work is a different discipline entirely.
Seventy percent of family wealth doesn't survive two generations. The reason isn't bad markets. The cause is failure to communicate, outdated documents, and no plan for preparing heirs. Beneficiary designations regularly override well-crafted wills. Trust structures created a decade ago no longer match current law or current family. The portfolio that built the wealth isn't the structure that transfers it. The work here is coordinating with your attorney to align documents, beneficiaries, gifting strategies, and trust funding with what you actually want to happen.
Every week, before any portfolio decision, John runs through four layers of market health: economic conditions, market internals, valuations, and sentiment. Each layer gets scored and those scores combine into a composite that maps directly to a portfolio posture, from aggressive on the positive end to defensive on the negative. The work is in the scoring. Once the scoring is done, the positioning follows. That removes one of the most dangerous things in investing: making it up as you go.
The protection gap quietly kills more plans than markets do. A significant net worth paired with inadequate liability coverage is a lawsuit away from a serious problem. Long-term care is more acute: a multi-year care event for one spouse can consume what was meant for the survivor. Most advisors relegate risk to a footnote because insurance conversations are uncomfortable. The math doesn't care. Coverage adequacy, umbrella sizing, long-term care planning, and life insurance structure sit alongside the portfolio in any complete plan.
These are the principles behind every plan John builds.
To begin a conversation, visit johnkoyle.com, use the retirement planning calculator at plan.johnkoyle.com, or reach John directly at john@redcedarwealth.com or (208) 915-8400. Initial consultations are complimentary and carry no obligation.