Handling Per Diem Payments in Construction Payroll
- Brittney Simpson
- 2 days ago
- 6 min read
A foreman on a commercial project three states away calls the office on a Friday afternoon.
He wants to know when the per diem is hitting. The crew has been out there for six weeks. They have been paying for their own hotel and meals. Payroll has reimbursed inconsistent amounts. One week it was right. The next one was short. Last week, it did not appear at all.
Payroll changed how they processed it compared to the week before.
The office manager, the payroll person, and the project manager all weigh in. Thirty minutes pass, and nobody has a clear answer.
This is a small moment. Construction companies often face this problem. They lack a clear, consistent process for managing per diem. These issues hurt employee trust. They also affect payroll accuracy and increase tax risks.
Let's walk through what is actually going on here and what getting this right actually looks like.
Why Per Diem Gets Complicated in Construction
On the surface, per diem sounds simple. You send workers to a job site away from home, cover meals and lodging, and pay a daily amount to offset those costs.
The payment structure causes the problem. How the company handles per diem determines whether the IRS treats it as tax-free or taxable. This affects both the company and the employee.
In many construction companies, per diem launches casually. Someone picks an amount, payroll adds it to the check, and it becomes the normal way of doing things. Nobody documents it as a reimbursement policy. Nobody ties it to IRS accountable plan rules. It keeps going until a problem appears. A tax audit, a prevailing wage review, or an employee asking why it is taxable can expose the weakness.
Consultant aside: I review payroll for construction companies that use per diem. I ask one simple question. Do they have a written accountable plan? Most do not. What they have is a habit, not a policy.
The Accountable Plan Distinction
This is the rule that drives the whole issue.
The IRS lets employers reimburse employees for business travel without taxes. This only works if the payments follow an accountable plan. To qualify, the employee must meet three rules. The expense must have a business purpose. The employee must report it. The employee must return any extra reimbursement.
When those conditions apply, the IRS excludes the per diem from wages. The payment is not included in gross income. It does not affect payroll taxes. It does not appear as taxable compensation on the W-2.
When those conditions do not apply, the per diem becomes taxable. This happens if the per diem is a flat add-on with no accountability. It also happens if it goes over IRS rates without proof. That triggers withholding, FICA taxes, and even higher labor-related costs.
Most companies fall into two groups. The per diem is either a documented reimbursement. Or it works like extra pay without the rules to make it tax-free. The second situation is far more common.
Consultant aside: The tax exposure goes both ways. The company may owe payroll taxes on amounts that should have been treated as wages, and the employee may owe income taxes on money that was never properly withheld.
The Consultant Lens
Here is the pattern I see most often.
A company lands its first out-of-town project. The owner decides on a daily amount, tells payroll to add it to the checks for that crew, and moves on. The next traveling project comes along and the same process repeats.
Over time, per diem becomes a standard expectation. Different managers handle it differently. The amounts vary. Sometimes it goes through payroll. Sometimes the company pays it outside payroll. Sometimes the company mishandles it. Nobody writes any of it down.
Then an audit, compliance review, or accountant examines the records. They find years of per diem payments treated as tax-free that were likely taxable.
Most contractors do not realize there is a problem when they set it up. They realize it when someone knowledgeable reviews it.
Let's Walk Through the Specific Issues
IRS per diem rates set the ceiling for tax-free payments.
The IRS publishes per diem rates by location, including meals, incidentals, and lodging. For construction work, the correct rate is based on where the employee is working.
If you pay at or below the IRS rate and the arrangement meets accountable plan rules, the payment can be tax-free. If you pay above that amount without documentation, the excess is taxable.
A common problem is that someone picks a round number that feels fair without checking whether it matches the actual IRS rate for that location.
Per diem and overtime do not mix the way most people assume.
For non-exempt employees, overtime is based on the regular rate of pay. That rate includes most forms of compensation, not just the hourly wage.
A properly structured per diem stays out of the regular rate because it is a reimbursement. But if the per diem functions like extra pay, it may need to be included in overtime calculations.
That is where companies get into trouble. They calculate overtime using only the base hourly rate while also paying per diem that may legally count as compensation. The result can be understated over time.
Prevailing wage projects add another layer.
On prevailing wage projects, per diem must also be reviewed carefully.
Bona fide per diem payments made under an accountable plan generally do not count as wages for prevailing wage purposes. But if the payment looks more like additional compensation than reimbursement, it may be treated as part of the wage calculation.
If your crew is on a public project and getting per diem as a flat amount in each paycheck, that setup may attract extra scrutiny during a compliance review.
Documentation is what makes the policy real.
A written accountable plan policy is essential if you want tax-free treatment to hold up. The policy should explain what expenses are covered, how reimbursement is calculated, how employees confirm travel or expenses, and what happens if too much is paid.
In many cases, the biggest issue is not the amount itself but the lack of documentation. Without a written policy, it becomes much harder to defend the payments as reimbursements.
Consultant aside: I have seen per diem arrangements that were reasonable in practice but completely undocumented. The company was getting favorable tax treatment by accident, and one audit away from losing it.
This is usually the point where a contractor starts thinking about how per diem has been handled across the last several years of out-of-town projects.
The amounts. The consistency. Whether there is anything written down. Whether crews on prevailing wage jobs were handled the same way as crews on private work.
Most of the time, they realize at least one of those answers is not what they would want it to be.
That is not a reason to panic. It is a reason to look at it clearly and fix it.
What I'd Recommend if This Sounds Familiar
Start by pulling together your current per diem amounts, how they are being processed through payroll, and whether you have any written policy at all. Then compare those amounts to IRS rates for the locations where your crews work and confirm whether the arrangement meets accountable plan rules.
If you perform prevailing wage work, that part of the review deserves extra attention.
Every company’s situation is a little different depending on the types of projects, the locations involved, and how the practice developed over time.
If you would like to walk through your setup together, you can schedule a call with me. We can review how the current arrangement works, where the gaps are, and what should be adjusted.
It is usually easier to fix than it first appears.
About Savvy HR Partner
Savvy HR Partner is an HR and payroll consulting firm that helps growing organizations build strong people operations. We specialize in HR strategy, compliance, employee relations, policy development, compensation guidance, and payroll support designed to scale with your business.
To learn more about our services, visit www.savvyhrpartner.com.
You can also follow Savvy HR Partner on LinkedIn, Facebook, and Instagram for practical HR insights and guidance for founders, leaders, and HR professionals.
If you are looking for HR support, you can schedule an appointment during HR Office Hours.
Comments