By Matt Schlossman, CFP®
Small 401(k) mistakes could be quietly chipping away at the retirement income you’re counting on. After working hard for decades, earning promotions, managing teams, and building meaningful savings, this is not what you want. For mid- to late-career professionals and executives with significant balances, even minor missteps can translate into major financial planning adjustments.
Over the years, I’ve seen that many of these mistakes don’t happen because someone is careless. More often, they happen because life gets busy and retirement accounts are left on autopilot. Small decisions that seem insignificant today can have a meaningful impact over time.
In this article, I outline five common 401(k) mistakes and what to do instead, so your retirement planning, tax planning, and investment management decisions stay aligned with your long-term goals.
Mistake #1: Not Contributing Enough
One of the most common 401(k) mistakes is simply not contributing enough, especially failing to capture the full employer match.
If your employer matches 50% of the first 6% you contribute, and you’re only contributing 4%, you’re effectively declining part of your compensation package. For a professional earning $200,000, that shortfall could mean thousands of dollars per year left unclaimed.
Over 20 years, those missed contributions can add up dramatically. Even for individuals with $1 million or more in assets under management, consistent maximum contributions can meaningfully affect flexibility in retirement planning.
Steps to take:
- Increase contributions at least to the level required to receive the full match.
- Review annual IRS contribution limits.
- If you receive bonuses or equity compensation, consider allocating a portion toward retirement savings.
Mistake #2: Choosing the Wrong Investment Options
Another common 401(k) mistake is misaligning investment selections. Many employees default into conservative options, even though they have a 10–15 year investment horizon. Others overweight company stock due to familiarity, or neglect to adjust their asset allocation as retirement approaches.
As you get closer to retirement, volatility becomes more significant. For example, a 20% decline in the market just five years before retirement can require substantial adjustments to your income strategy. Thoughtful investment management means looking at the full picture.
Your 401(k) shouldn’t be viewed in isolation. Ideally, it works alongside your IRAs, brokerage accounts, and other assets as part of one coordinated investment strategy.
Steps to take:
- Review your allocation at least annually.
- Consider how your 401(k) investments integrate with taxable accounts, IRAs, and equity compensation.
- Align allocations with your time horizon and income distribution plan.
Mistake #3: Taking Early Withdrawals or Loans
Accessing 401(k) funds early can be expensive. Withdrawals made before age 59½ typically trigger a 10% early withdrawal penalty, as well as ordinary income taxes on the distribution. While loans are often perceived as safer because you’re “paying yourself back,” they still come with risks. For example, the borrowed amount stops compounding, repayment occurs with after-tax dollars, and job changes can trigger immediate repayment requirements. For pre-retirees with significant assets, safeguarding compounding during the final accumulation years is particularly important.
Steps to take:
- Build a separate (liquid) emergency reserve.
- Explore other liquidity options before tapping retirement assets.
- Coordinate withdrawal strategies with broader tax planning.
Mistake #4: Ignoring Fees
Fees are one of the most overlooked mistakes when it comes to 401(k) planning. Most plans include expense ratios on mutual funds, administrative fees, and potential advisory or recordkeeping costs. Even a small difference of 1% in annual fees can significantly reduce the long-term value of your portfolio. Unfortunately, many professionals fail to review their plan’s fee disclosure documents or assume that employer-sponsored plans are automatically low-cost.
While a single year of higher fees may not seem significant, the cumulative impact over decades can materially reduce portfolio growth.
Steps to take:
- Review expense ratios within your plan.
- Compare available fund options.
- Consider whether rolling assets into an IRA at retirement could provide cost or flexibility gains.
Mistake #5: Forgetting About the 401(k) at Your Last Job
Career changes often result in orphaned retirement accounts, leaving individuals with several options when leaving a job. You can leave the account where it is, roll it into your new employer’s 401(k), transfer it into an IRA, or cash it out (although cashing out is usually not advisable).
Many people forget these accounts exist, while others end up with multiple small accounts scattered across different employers. Consolidating these accounts can simplify tracking, improve coordination of investment management, streamline beneficiary designations, and provide more flexibility in tax planning strategies. For executives and small business owners with multiple retirement vehicles, staying organized becomes increasingly important as retirement approaches.
Steps to take:
- Inventory all retirement accounts.
- Confirm beneficiaries are current.
- Evaluate rollover options in the context of your overall financial planning.
Avoid 401(k) Mistakes With a Coordinated Financial Plan
Many 401(k) mistakes happen because life gets busy and financial decisions become fragmented. In my experience, the most effective retirement strategies come from looking at the entire financial picture rather than making isolated decisions about individual accounts.
As an independent fee-only fiduciary firm, CGN Advisors helps clients integrate retirement planning, tax planning, equity compensation analysis, and investment management into a single strategy. In the first conversation, we often uncover overlooked accounts, outdated allocations, or missed opportunities that materially affect long-term outcomes.
If you’re within 10 years of retirement and want to feel confident that your 401(k) fits into your broader financial advisor relationship, schedule a meeting with our team by calling (785) 340-3434.
Frequently Asked Questions About How to Avoid 401(k) Mistakes
What are the most common 401(k) mistakes employees make?
Some of the most common 401(k) mistakes include not contributing enough to receive the full employer match, choosing investments that don’t align with your retirement timeline, ignoring fees, taking early withdrawals, and forgetting about old employer plans. These missteps can reduce long-term growth and limit your retirement income.
Should I roll over my old 401(k) when I change jobs?
Rolling over an old 401(k) into an IRA or a new employer’s plan can simplify account management and provide more control over investments and beneficiary designations. CGN Advisors often helps professionals evaluate rollover options to align their retirement accounts with their broader tax planning and retirement strategy.
How much should I contribute to my 401(k) to avoid retirement planning mistakes?
At minimum, you should contribute enough to receive your full employer match, since it’s essentially additional compensation. Many mid-career and higher-income professionals benefit from contributing the IRS maximum each year, especially during their peak earning years, to strengthen long-term retirement stability.
About Matt
Matt Schlossman, CFP®, is a Financial Advisor at CGN Advisors, a Fee-Only financial advisory firm based in Manhattan, Kansas. He works directly with clients while also partnering with fellow advisors to support their client relationships. Matt’s greatest passion in his role is helping reduce financial stress by bringing clarity to complex financial situations and confidence to important decisions. He believes that when clients understand their financial picture, they are better equipped to focus on what matters most in their lives. Matt also has a strong interest in tax planning and enjoys collaborating closely with clients and their CPAs to develop and implement effective tax strategies.
Matt earned his degree in personal financial planning, with a minor in business, from Kansas State University and holds the CERTIFIED FINANCIAL PLANNER® designation. He values CGN Advisors’ collaborative, team-oriented culture and finds it both rewarding and energizing to work alongside colleagues in pursuit of the best outcomes for clients.
Beyond his work at CGN, Matt has been actively involved with the Financial Planning Association (FPA) for nearly three years, serving on the NexGen GATHER planning committee. In this role, he helps organize the FPA’s annual national conference, which supports the next generation of advisors by providing community, education, and resources to help professionals grow with confidence.
Outside of the office, Matt is married to his high school sweetheart, Randi, and they enjoy life with their young son, Teddy. In his free time, he loves spending time with his family, cheering on K-State sports, golfing, and watching stand-up comedy. To learn more about Matt, connect with him on LinkedIn.
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