Computing the Trust Fund Recovery Penalty Amount from Form 941

When a business falls behind on payroll taxes, the people running it want to know one number: how much can the IRS come after me for personally? That number is the trust fund recovery penalty. It is computed, not estimated, and it is usually smaller than the total balance on the business account.

What the penalty covers

IRC 6672(a) imposes a penalty on any person required to collect, account for, and pay over tax who willfully fails to do so, equal to the total amount of the tax evaded, or not collected, or not accounted for and paid over. For payroll, that is the tax withheld from employees and held in trust for the government.

IRM 5.7.4.3 states it directly for Form 941: the TFRP is equal to the amount of the employees' share of FICA and withholding. Form 943 and Form 944 follow the same rule. For Form 945, which reports only withheld income tax, the TFRP is 100 percent of the tax.

Trust fund vs. non-trust fund on Form 941

The penalty is a dollar-for-dollar match to the unpaid trust fund portion. It does not include the business's own penalties, like the failure-to-deposit penalty, or interest on the business account.

Step 1: split the quarter

Say a business reports $120,000 of wages for the second quarter of 2026, all subject to social security and Medicare, no tips, and no employee over the Additional Medicare threshold. Federal income tax withheld is $14,400.

Step 2: apply the payments the IRS way

Here is where people get the number wrong. Payments made on the quarter do not automatically reduce the trust fund. IRM 5.7.4.3.1 sets the sequence for undesignated payments on an employment tax period:

1. Non-trust fund portion of tax (employer's share of FICA)
2. Trust fund portion of tax (withholding and employee FICA)
3. Assessed lien fees and collection costs
4. Assessed penalty
5. Assessed interest
6. Accrued penalty to the date of payment
7. Accrued interest to the date of payment

Federal tax deposits, and payments on or before the due date, go to steps 1 and 2. Undesignated payments after assessment, and involuntary payments, run through all seven. Designated payments are applied as designated.

That is why designation matters. If the business had instead made a $12,000 voluntary payment designated in writing to the trust fund portion, the trust fund left unpaid would be $11,580. The full comparison is in designating payroll tax payments.

Step 3: add the quarters

The TFRP is computed quarter by quarter and added up. A business that missed three quarters has three trust fund figures, each reduced by its own payments. The IRS uses its Automated Trust Fund Recovery system to pull the open modules and compute the balance, per IRM 5.7.4.3, but you can do the same arithmetic from the returns and the account transcripts.

Details that change the number

• Additional assessments. IRM 5.7.4.3 says payments that satisfied the original trust fund amount generally may not be reapplied to a later additional assessment on the same module for TFRP purposes, with a narrow exception for reversed employer credits.
• Credits. Payroll tax credits claimed on the return can reduce tax, and reversals of improperly claimed credits can increase it, with special rules in IRM 5.7.4.3.
• Unfiled quarters. The IRS can prepare returns under IRC 6020(b) and include them in the computation once they are submitted for processing.

Multiple responsible persons

The IRS can assess the full penalty against every person who was both responsible and willful. It does not collect the trust fund more than once. Payments by the business or by any assessed person reduce what remains collectible from the others, which IRM 5.7.4.5 refers to as cross-referencing. If one person pays more than a proportionate share, IRC 6672(d) gives that person a right of contribution from the others.

Who counts as responsible and what willful means are covered in Trust Fund Recovery Penalty. The business side is in Payroll Tax Problems for Businesses.

Worked example: Additional Medicare and Form 945

Two refinements change the trust fund number in specific cases. First, Additional Medicare Tax withholding. Employers withhold an extra 0.9 percent on an employee's wages above the withholding threshold, reported on line 5d of Form 941, and there is no employer match. All of it is employee money, so all of it is trust fund. If a quarter includes $40,000 of wages subject to Additional Medicare Tax withholding, line 5d is $360, and the full $360 is added to the trust fund portion.

Second, Form 945. That return reports withheld federal income tax on nonpayroll payments, such as backup withholding and certain pension and gambling withholding. IRM 5.7.4.3 says the TFRP for Form 945 is 100 percent of the tax, because none of it is an employer's own tax. A business that withheld $5,000 of backup withholding and never paid it over has a $5,000 trust fund balance, with no employer share to absorb payments first.

Worked example: partial responsibility

Responsibility is determined person by person and quarter by quarter. Using the three-quarter table above, suppose one officer joined the company in July 2026 and had check-signing authority only for the third and fourth quarters. If that officer is found responsible and willful only for those quarters, the exposure is $24,100 plus $17,950, or $42,050, not the full $62,810. The founder who ran the company all year could face the full $62,810.

IRM 5.7.4.5 tells revenue officers to state on Form 4183 whether each person is fully or partially responsible, and to address how payments by a partially responsible person should be cross-referenced. When one person pays, the IRS reduces the shared balance for everyone liable for that quarter, so the founder's exposure falls by whatever the newer officer pays toward the third and fourth quarters.

A short checklist

1. Pull each Form 941 and split line 3, half of lines 5a through 5c, and all of line 5d into trust fund.
2. List every payment by date and type: deposit, payment with return, later voluntary payment, levy.
3. Apply them in the IRM 5.7.4.3.1 sequence unless a valid designation says otherwise.
4. Total the unpaid trust fund by quarter, then by person based on the quarters each was responsible.

Why the IRS number can be higher than yours

Three common reasons. First, the IRS may have applied a payment to a different quarter or to a non-trust fund module like Form 940 or Form 1120, which IRM 5.7.4.3 allows for undesignated payments. Second, an additional assessment for a quarter may have increased the tax without any payment being reapplied to it. Third, a quarter you thought was filed may have been assessed under IRC 6020(b) on estimated figures. Each one has a fix, but only if you find it before the penalty is proposed. The Letter 1153 that proposes the penalty starts an appeal window, and the computation is easiest to correct before that letter goes out.

Getting the computation right before any interview also makes the rest of the case easier, because responsibility and willfulness are argued against a known number rather than an IRS estimate.

The bottom line

The TFRP is withheld income tax plus the employee share of FICA, minus whatever payments actually landed on the trust fund portion. Undesignated payments hit the employer's share first. Build the number quarter by quarter from the 941s and the transcripts before anyone sits down for a Form 4180 interview. The firm's payroll taxes page is a place to start if the number is big.