For companies with mobile employees, driving remains essential to day-to-day business. But many reimbursement programs were built with a different economy, one with more stable fuel prices and lower vehicle costs.
In 2026, a new reality for gas prices
Sharp swings in gas prices, rising operating expenses, and tighter budgets are revealing the weaknesses of traditional reimbursement models.
Programs built around flat car allowances, fuel cards, or standard mileage reimbursement may seem familiar and easy to manage, but they often create hidden costs, administrative headaches, and employee frustration.
More importantly, these programs are not nimble enough to keep pace in an ever-changing environment in which we do business. These programs can influence employee behavior in ways that undermine productivity, sales activity, and overall company performance.
As costs continue to rise and uncertainty is the reality of today’s business environment, as fuel volatility becomes the new normal, organizations need reimbursement strategies that are flexible, accurate, and tailored to real-world driving conditions.
The "Triple Threat" of Hybrid Reimbursement Programs
Many companies try to achieve balance or make up for the deficiencies of an auto allowance by adding another reimbursement method to the car stipend. A lot of well-intentioned companies try to make up for deficiencies in the auto allowance by increasing it, adding a fuel card or fuel reimbursement, or adding an additional cents-per-mile payment to the allowance. Unfortunately, this creates tax consequences for the company and drivers.
At first glance, this approach seems flexible and employee-friendly. In practice, however, it often creates a costly “triple threat”:
- Over reimbursement
- Administrative complexity
- Increased exposure to fuel volatility
- Creating a larger tax event
1. Over-Reimbursement and "Double Dipping."
When employees receive both fuel and a car stipend, companies can inadvertently pay for the same expense twice, once at the gas pump and again through auto allowance formulas. Without strong controls and continuous monitoring, these overlapping payments are difficult to detect. Over time, the extra costs can add up quickly.
2. Administrative Complexity.
Adding another reimbursement method makes it harder for the company to manage the program.
Administratively, organizations need to track:
• Fuel purchases
• Mileage logs
• Business vs. personal use
• Payroll reporting
• Taxable benefits
• Compliance documentation
That complexity creates more opportunities for errors, tax waste, and reimbursement leakage. In many cases, companies detect problems only during periodic reviews or audits rather than proactively identifying them in real time.
3. No Protection Against Fuel Price Volatility.
Hybrid programs also make budgeting harder during periods of rising fuel prices. For example:
• The company absorbs fuel price increases through fuel cards or reimbursements
• Employees continue receiving fixed allowances
• Costs become harder to predict month to month
When gas prices spike unexpectedly, reimbursement costs can rise rapidly, with little built-in protection for employers.
The Hidden Cost of Fuel Cards
Fuel cards are often seen as a convenient solution, but convenience can come with hidden risks.
Many fuel card programs rely heavily on the honor system. That makes personal-use tracking difficult and time-consuming, especially when gas prices are high.
Common problems include:
• Fueling personal vehicles
• Filling gas containers or recreational equipment
• Excessive personal mileage
• Incorrect business-use reporting
Even companies with chargeback policies often struggle to accurately recover these costs. In some cases, the time spent monitoring fuel usage outweighs the program's value.
Over time, fuel card misuse can become one of the highest hidden costs in a vehicle reimbursement program.
How Reimbursement Programs Influence Employee Behavior
Fuel volatility affects more than budgets. It also changes how employees approach their work.
When drivers perceive reimbursement programs as unfair or outdated, companies often observe behavioral changes that reduce efficiency and increase compliance risk.
Mileage Padding
Although it may seem counterintuitive, many organizations that reimburse employees at the IRS mileage rate see reported mileage increase when gas prices rise sharply. When employees believe their actual vehicle expenses are no longer fully covered, some may consciously or unconsciously compensate by overstating business travel or inflating mileage logs.
This behavior is more likely when reimbursement programs feel disconnected from real-world driving costs. As fuel prices rise, employee satisfaction with fixed car allowances often declines significantly, placing greater pressure on employers to ensure reimbursement programs remain fair, competitive, and aligned with current operating expenses.
This becomes more common when reimbursement programs feel disconnected from real driving costs. Consequently, as gas prices have risen, employees receiving a car allowance have seen their allowances decline sharply.
Service and Sales Avoidance
Employees may also avoid long-distance trips if they believe those trips cost them out of pocket. That can lead to fewer:
• Client visits
• Service calls
• Sales meetings
• Territory expansion efforts
Over time, this hurts customer engagement and limits growth opportunities.
For companies that rely on field sales or service teams, a reimbursement strategy can directly impact business performance.
The Problem with the IRS Mileage Rate
The IRS standard mileage rate is often viewed as the simplest reimbursement option. However, simple does not always mean accurate.
The IRS rate is based on historical national averages and combines:
• Fuel
• Insurance
• Maintenance
• Depreciation
• Other operating costs
The problem is that real driving costs vary widely by location, vehicle type, and fuel prices. As a result:
• Employees who drive fewer miles are under-reimbursed
• High mileage drivers are over-reimbursed, often, much more than their actual expenses
This imbalance can unintentionally encourage excessive driving or mileage inflation.
At the same time, employees may still feel frustrated because the IRS rate does not adjust quickly enough to reflect sudden local fuel price increases.
Why Flat Car Allowances Fall Short
Flat taxable car allowances remain common because they are simple to administer. Unfortunately, they are also among the least efficient reimbursement methods.
The biggest issue is taxation.
Because allowances are treated as taxable income, employees can lose 30% or more of the payment to payroll and income taxes before they even pay for fuel or vehicle maintenance. The company also pays payroll taxes. This creates significant tax waste for both employers and employees.
Flat allowances also fail to account for differences in business mileage. An employee driving 500 business miles per month may receive the same allowance as someone driving 2,000 miles.
That may be equal, but it is not equitable.
When fuel prices rise, the value of that already-taxed allowance shrinks even further, increasing financial pressure on employees.
Fleet Vehicles and the Personal Use Challenge
Some organizations try to avoid reimbursement issues by providing company-owned vehicles instead.
Fleet programs can improve consistency and control, but they also introduce new challenges, especially around personal use.
Most fleet policies allow employees to use company vehicles for commuting and limited personal driving. In return, employees usually must:
• Repay personal fuel expenses, or
• Report personal use as taxable income
Tracking those expenses accurately becomes much harder during periods of fuel volatility.
Family use also increases costs, but it increases your liability for the business.
Without real-time tracking and intelligent reporting tools, companies often end up subsidizing personal driving without fully understanding the true cost.
The Path Forward: Smarter, More Flexible Reimbursement Programs
As fuel costs continue to fluctuate, more organizations are moving away from “traditional” reimbursement models and toward data-driven vehicle programs.
One of the most effective approaches is the Fixed and Variable Rate (FAVR) model.
Unlike flat allowances or standard mileage reimbursement, FAVR separates:
• Fixed costs like insurance and depreciation
• Variable costs like fuel and maintenance
This allows reimbursements to adjust based on real-world driving costs and local market conditions.
The result is:
• More accurate reimbursement
• Better cost control
• Reduced tax waste
• Improved fairness for employees
• Stronger compliance
• Better budget predictability
Most importantly, intelligent reimbursement programs create balance. They help companies fairly reimburse employees without encouraging wasteful behavior or exposing the organization to unnecessary financial risk.
In today’s unpredictable fuel market, that balance is no longer optional; it is essential.
Contact mBurse today to find solutions to your vehicle reimbursement challenges.
