A true-up is an accounting adjustment that reconciles an estimated payment with the actual amount owed once the real figure is known. Whoever overpaid gets money back; whoever underpaid sends the difference. The mechanic is the same whether you are looking at a 401(k) match, a commercial lease, a corporate acquisition, a licensing royalty, or your own tax return, and understanding what a true-up is matters because several of them quietly decide how much money ends up in your pocket.
How a True-Up Works
Every true-up starts with a timing problem. A payment has to go out before anyone knows the exact amount. An employer withholds income tax before the year’s wages are final. A commercial tenant pays monthly rent before the building’s actual operating costs are tallied. A buyer wires funds at closing before the target company’s final balance sheet is done.
The workaround is to pay based on an estimate and reconcile later. When the verified number arrives, the parties settle the gap. That settlement is the true-up.
The concept is more familiar than the word. Filing a federal tax return is a true-up. Your employer withholds throughout the year based on estimates; when you file, you calculate the actual liability, compare it to what was withheld, and either get a refund or pay the balance.1Internal Revenue Service. Estimated Tax
401(k) Matching True-Ups
This is the true-up most employees encounter personally, and the one where missing the rule can cost real money. It applies when an employer calculates matching contributions on a per-paycheck basis while the match formula was designed around annual totals.
Here is the setup. The 2026 elective deferral limit for 401(k) plans is $24,500, or $32,500 if you are 50 or older thanks to an $8,000 catch-up contribution.2Internal Revenue Service. 401(k) Limit Increases to $24,500 for 2026, IRA Limit Increases to $7,500 Say your employer matches on the first several percent of your salary under a safe harbor formula.3eCFR. 26 CFR 1.401(k)-3 – Safe Harbor Requirements If you front-load your contributions and hit the $24,500 cap by September, your remaining paychecks show zero deferrals. Under a strict per-paycheck match, zero deferrals means zero employer match for October through December. That is money left on the table.
A plan with a true-up provision fixes this. After the year ends, the employer recalculates your match against full-year compensation and full-year deferrals, then deposits whatever the per-paycheck method shorted you. Not every 401(k) plan includes it. The provision has to be written into the plan document, so ask your plan administrator before assuming you are covered.4Internal Revenue Service. Retirement Topics – Contributions
SECURE 2.0 adds a wrinkle. Employees aged 60 through 63 qualify for an enhanced catch-up of $11,250 in 2026 rather than the standard $8,000.2Internal Revenue Service. 401(k) Limit Increases to $24,500 for 2026, IRA Limit Increases to $7,500 Reaching that higher combined limit faster widens the per-paycheck matching gap, which makes a true-up provision even more valuable for workers in that age band.
Bonus True-Ups and Overtime
Companies often pay provisional bonuses through the year based on unaudited metrics like quarterly sales or production. Once audited annual results land, a true-up settles the difference. If results came in below projections, employees may owe overpayments back. If the company outperformed, an additional payment goes out.
What often gets missed is that a bonus true-up can trigger a separate obligation under the Fair Labor Standards Act. When a non-discretionary bonus is paid to an employee who worked overtime during the bonus period, the employer must recalculate the regular rate of pay and pay any additional overtime premium owed. The regular rate includes all remuneration for employment, and non-discretionary bonuses count.5Office of the Law Revision Counsel. 29 USC 207 – Maximum Hours
A bonus is “discretionary” and excludable from the regular rate only if the employer decides both whether to pay it and how much to pay at or near the end of the period, with no prior promise or formula creating an expectation.5Office of the Law Revision Counsel. 29 USC 207 – Maximum Hours Bonuses tied to attendance, safety records, production efficiency, or any pre-set criteria fail that test. A January 2026 Department of Labor opinion letter reinforced the point.6U.S. Department of Labor. FLSA Opinion Letter FLSA2026-2 Employers who pay a bonus true-up without going back to recalculate overtime risk a federal wage violation.
Working Capital True-Ups in Mergers and Acquisitions
In corporate acquisitions, the purchase price rarely stays exactly where it was on closing day. Buyer and seller agree on an enterprise value assuming a normalized level of working capital, then reconcile after closing once the actual balance sheet is verified.
Net working capital here means the target’s current assets minus current liabilities, excluding cash and debt. It represents the operating liquidity the business needs to function on day one under new ownership. The purchase agreement fixes a “target” figure, usually based on historical averages.
At closing, the buyer pays based on an estimated working capital number because the final books are not ready. The agreement then gives the buyer a window, commonly 60 to 90 days, to prepare a closing statement showing the actual working capital delivered.
The true-up is the difference between the actual number and the target. If the seller delivered more liquidity than required, the buyer pays the surplus. If the seller fell short, the seller pays back the shortfall, often out of an escrow account funded at closing for exactly that purpose. Disputes are common, and most purchase agreements route contested items to an independent accounting firm whose decision binds both sides.
Commercial Lease Operating Expense True-Ups
If you lease commercial space, you almost certainly deal with an annual true-up on operating expenses. It goes by CAM reconciliation in many leases, for common area maintenance. Most commercial leases require the tenant to pay a monthly estimate toward the building’s shared costs: property taxes, insurance, maintenance, common-area utilities, and similar line items.
Those monthly estimates come from the landlord’s budget at the start of the year. When the year ends and actual invoices are in, the landlord calculates each tenant’s proportionate share based on occupied square footage, compares total estimated payments to actual costs, and issues a reconciliation statement.
Overpayments usually appear as credits against future rent. Underpayments arrive as an invoice. Most leases require the statement to be delivered within 30 to 90 days of fiscal year-end. Review it. Common errors include expenses miscoded to the wrong property, charges that violate negotiated caps, and costs the lease specifically excludes from the tenant’s share. Catching a mistake before paying is far easier than recovering money after.
Usage, Royalty, and Self-Funded Health Plan True-Ups
The same estimate-and-reconcile pattern shows up in several commercial contracts.
Software and Cloud Services
Technology vendors offering subscriptions or cloud services often bill against tiered pricing or minimum usage commitments. A client pays a flat monthly fee for a baseline of service, and at quarter- or year-end the vendor reviews actual consumption against what was billed. Overages produce an additional charge. Underuse of a guaranteed minimum depends on the contract: some agreements offer no refund for unused capacity, others roll unused amounts as credits.
Royalties and Licensing
Licensing agreements for patents, trademarks, or proprietary software commonly tie payments to the licensee’s sales or production volume. The licensee sends estimated royalties monthly or quarterly based on preliminary reports. The licensor later audits the licensee’s final sales records, compares total provisional payments to the verified calculation, and settles any difference. Audit rights exist in these contracts precisely so the true-up is enforceable.
Self-Funded Health Insurance
Employers who self-fund health coverage carry the financial risk for employee claims rather than paying a fixed premium to a carrier. They typically hire a third-party administrator and pay a projected monthly amount. At year-end, the administrator reconciles claims paid against amounts received. A quieter year produces a refund; a heavier one produces a bill. Because a few large claims can swing the number, many self-funded employers carry stop-loss insurance to cap their exposure.
Tax and Utility True-Ups You Already Do
Self-employed individuals, freelancers, and small business owners run a true-up every time they file an annual return. Quarterly estimated payments go in based on projected income; the return reveals whether the projection was right. Individuals expecting to owe $1,000 or more generally need to make estimated payments, and corporations face the same requirement at a $500 threshold.7Internal Revenue Service. About Estimated Taxes Underpaying carries a penalty even in a year that ends in a refund, so the estimates matter.
Property tax proration at a real estate closing follows the same logic. The buyer and seller split the year’s tax based on the closing date, using an estimate because the actual bill for the year may not have arrived yet. When the real bill comes in, lenders adjust escrow accounts accordingly, sometimes changing the monthly mortgage payment. Buyers who do not anticipate the shift can be caught off guard.
Homeowners with grid-tied solar see this too, through net energy metering. Electricity you generate but do not use flows back to the grid and earns credits; months when your panels produce less pull those credits back down. At the end of a 12-month billing cycle, the utility performs an annual true-up. Surplus credits get cashed out, often at a rate well below what you pay to buy electricity. That true-up rate is worth knowing before sizing a system, because overproducing by a wide margin does not translate into proportional savings if the payout is a few cents per kilowatt-hour.