The Mid-Year 401(k) Checkup: How to Do It With AI in 20 Minutes

The calendar just crossed the halfway mark, and your 401(k) has been running on autopilot since January. That is usually fine. Autopilot is what makes a retirement account work while you ignore it. But autopilot also means a settings mistake you made in January has been quietly repeating on every paycheck for six months, and the fixes get cheaper the sooner you catch them.

Call this the halfway checkpoint. It is not a rebalancing sprint or a market call. It is a twenty-minute look at four dials that you can actually control, unlike the market: your contribution pace, your employer match, your fund fees, and your allocation drift. Three of those four are pure settings, and settings are exactly the kind of thing you fix once and forget.

An AI is a genuinely good assistant for this, not because it knows your plan, but because it will take the scattered numbers off your statement and turn them into a clean summary without editorializing about the stock market. What it must never do is recommend a fund or predict returns, and this walks through how to keep it in its lane while it does the useful part.

The four-dial checkup

The whole checkup is four questions, in order of how much money they tend to move. Match first, because missing it is the most expensive mistake and the easiest to fix. Fees last, because they matter enormously over decades but not in a single afternoon.

None of these requires a spreadsheet or a login you do not already have. Your latest 401(k) statement and your plan's fund list have everything, and the AI does the tedious sorting once you paste the numbers in.

The match: the dial that moves the most money

The employer match is the closest thing to free money in your financial life, and a surprising number of people leave part of it behind. The match is typically written as a percentage of your pay up to a cap, like 100% of the first 4% you contribute, or 50% of the first 6%. To earn the whole thing, your own contribution rate has to reach the cap. Contribute less and you forfeit part of the match on every single paycheck.

This is not a rare slip. A widely cited Financial Engines study of 4.4 million savers found that about one in four workers miss some of their full match by not contributing enough, leaving a median of roughly $1,336 a year on the table, money that compounds into far more over a career. The average employer match has actually grown generous: Vanguard's How America Saves 2025 report put the average match at a record 4.7% of pay, with 88% of participants offered one. The more generous the match, the more it costs to miss.

There is a second, sneakier way to miss the match, and it catches diligent savers rather than under-savers: front-loading. If you push your contribution rate high to hit the $24,500 limit early, say by September, and your plan does not offer a true-up, your paycheck contributions stop for the rest of the year, and so does the per-paycheck match. You can finish the year having hit the limit but skipped three months of matching. Whether this applies turns on one input I cannot know for you, which is whether your plan trues up at year-end, so that is the single thing worth confirming with HR before you front-load anything.

The 2026 numbers you are working against

The ceilings changed this year, so a rate you set in a prior year may no longer do what you think. For 2026 the IRS raised the employee contribution limit to $24,500, and the catch-up amounts went up too.

Two details on that table matter. The higher $11,250 catch-up is a new SECURE 2.0 feature that applies only in the years you turn 60 through 63, then reverts to the standard $8,000. And starting in 2026, if your wages with the employer topped $150,000 the year before, your catch-up contributions must go in as Roth rather than pre-tax, per the IRS. Those limits count only your own money; the employer match sits on top and does not eat into them.

Reading your fund fees

Fees are the quietest dial and the one that compounds hardest, so it is worth two minutes to find yours. Every fund in your plan has an expense ratio, an annual percentage skimmed off your balance whether the fund rises or falls. It never shows up as a line item you pay, which is exactly why it gets ignored.

The good news is that plan fees have fallen a lot. In 2024, 401(k) participants in equity mutual funds paid an average expense ratio of 0.26%, well below the 0.40% industrywide average, according to the Investment Company Institute. Inside a good plan, a broad index fund often charges under 0.10%, while some actively managed or older target-date options still run 0.50% to over 1%. On a $100,000 balance, the gap between 0.10% and 1.00% is about $900 a year, and it repeats every year while it compounds against you. You do not need the cheapest fund on earth; you need to notice if you are sitting in an expensive one when a near-identical cheap option is on the same menu.

Run the checkup with AI

Now hand the sorting to a chatbot. The value here is not insight, it is organization: you paste your real numbers, and it lays out whether you are capturing the match, what your fees cost in dollars, and how far your mix has drifted, without wandering into recommendations. Swap your figures into the brackets.

You are helping me run a mid-year checkup on my own 401(k).
Use only the numbers I give you. Do not recommend any fund,
do not predict markets, and do not invent my plan's rules.

My details:
- Salary: [$80,000]
- My current contribution: [10% of pay]
- Employer match formula: [100% of the first 4% of pay]
- Current balance: [$60,000]
- My funds and fees: [S&P 500 index 0.04%], [target-date 0.55%]
- Roughly [70%] of my balance is in the target-date fund.
- My target mix: [80% stocks / 20% bonds]
- My actual mix now: [88% stocks / 12% bonds]

Do the following:
1. Am I contributing enough to earn the full match? By how much
   over or under the cap?
2. Estimate my annual fee cost in dollars from the blended
   expense ratio on my balance.
3. Is my actual mix drifted from my target, and by how much?
4. Give me the single highest-value action, framed as a
   general principle, not a fund recommendation.

State clearly that this is general organization of my numbers,
not investment advice.

Hand it your real figures and the answer lands close to this.

The reason to keep the AI on this leash is that if you ask it what to invest in, it will happily name funds and even guess returns, and it has no business doing either with your retirement. Let it total your fees and measure your drift, which is arithmetic, and take the actual investment decisions to your plan documents or a fiduciary advisor.

On rebalancing, and where I'd be careful

Of the four dials, rebalancing is the one people most often overdo, so here is where I land on it. Drift is real and worth fixing: after a strong stock run, a mix you set at 80/20 can quietly become 88/12, and you are now taking more risk than you signed up for. Nudging it back once or twice a year when it strays more than about five points is sound housekeeping.

What I would not do is treat a mid-year checkup as license to trade around a market view. The checkup is for the dials you control, and the market is not one of them. If a chatbot, a headline, or a gut feeling is pushing you to move money because of where stocks might go next, that is the moment to close the tab. Fix the settings, confirm the match, note the fees, correct real drift, and let the autopilot you just tuned carry the account for another six months. The people who win at this are boring on purpose.

FAQ

What is the 401(k) contribution limit for 2026?

The 2026 employee limit is $24,500, up from $23,500 in 2025, per the IRS. Age 50 and up can add an $8,000 catch-up for a $32,500 total, and a new SECURE 2.0 rule gives those who turn 60 to 63 during the year an $11,250 catch-up, for $35,750 where the plan allows. If your prior-year wages with the employer topped $150,000, your 2026 catch-up must go in as Roth. These limits are your own contributions only; the employer match is on top.

How do I know if I am getting my full employer 401(k) match?

Find your match formula, usually a percentage up to a cap, like 100% of the first 4% of pay. Then confirm your own contribution rate at least reaches that cap. Contribute less and you forfeit part of the match each paycheck; about one in four workers do, per a Financial Engines study. Watch the timing too: maxing the annual limit before December in a plan with no true-up can cost you the match on later paychecks, so pace contributions across the year.

What is a good expense ratio for a 401(k) fund?

Lower is better. In 2024, 401(k) equity-fund investors paid an average of 0.26%, versus 0.40% industrywide, per the ICI. Broad index funds in good plans often charge under 0.10%, while some active or target-date options run 0.50% to over 1%. The fee is annual and comes out whether markets rise or fall, so on $100,000 the gap between 0.10% and 1.00% is about $900 a year. Favor the cheapest option that fits your target mix.

Should I rebalance my 401(k) mid-year?

Only if it has drifted meaningfully from your target, not on a market hunch. Rebalancing sells a little of what grew and buys what lagged to restore your intended split. After a strong run, an 80/20 mix can drift several points heavier in stocks, raising your risk. Most people are fine checking once or twice a year and adjusting only when a category is more than about five points off target.

Disclaimer

This article is an educational explainer, not financial, tax, or investment advice, and it recommends no specific fund, allocation, or product. Contribution limits, catch-up amounts, and plan rules are current as of July 2026 and vary by plan; they change over time. AI here organizes the numbers you supply and should not be used to pick investments or forecast returns. Confirm every figure with your plan documents and a qualified professional before acting. All figures are as of July 18, 2026.

If this was useful, these go next to it: for the bigger picture on letting AI see your whole money setup, ChatGPT Personal Finance: What It Actually Does. To decide where to park cash you are not investing, Should You Lock a CD Before the Fed Meeting?. And to turn a rate headline into what it means for you, Fed Rate News Explained: What It Means for Your Mortgage and Card.

Sources

• IRS, 401(k) limit increases to $24,500 for 2026, IRA limit increases to $7,500 (catch-up $8,000; $11,250 for ages 60-63; Roth catch-up over $150,000): https://www.irs.gov/newsroom/401k-limit-increases-to-24500-for-2026-ira-limit-increases-to-7500
• IRS, Notice 2025-67, 2026 amounts relating to retirement plans: https://www.irs.gov/pub/irs-drop/n-25-67.pdf
• Vanguard, How America Saves 2025 (average employer match 4.7% of pay, 88% offered a match): https://corporate.vanguard.com/content/dam/corp/research/pdf/how_america_saves_report_2025.pdf
• Investment Company Institute, average 401(k) equity mutual fund expense ratio 0.26% in 2024: https://www.ici.org/news-release/25-low-expense-ratios-benefit-retirement-savers
• SHRM / Financial Engines, One in Four Workers Miss Out on Full 401(k) Match (median $1,336/year): https://www.shrm.org/topics-tools/news/benefits-compensation/one-four-workers-miss-full-401k-match