Mileage Reimbursement: When to Use the IRS Rate

Let’s set the record straight: no, the IRS mileage rate is not a required mileage reimbursement rate.

Set by the IRS, the standard business mileage rate serves as a “safe harbor.” Companies use it to calculate the tax-deductible costs of operating an automobile for business. The IRS calculates the mileage rate, also known as the federal mileage reimbursement rate among other names, annually. Why? Because it’s meant to reflect the “fixed and variable costs of operating an automobile.” However, it is not a prescribed mileage reimbursement rate. It’s a rate at which employees can claim tax deductions for un-reimbursed driving expenses. The only justification the IRS requires is a compliant mileage log.

Organizations can choose to use flat car allowances, Fixed and Variable Rate (FAVR) reimbursement programs, the IRS rate, or a cents-per-mile rate that differs from the IRS rate when reimbursing employees. With so many options, it’s easy to see why there’s confusion. And why companies often just default to using the IRS rate for mileage reimbursement. Companies will find the federal mileage reimbursement rate simple to use and it can be paid tax-free. However, it’s important to know the drawbacks. Additionally, when the IRS mileage rate makes the most sense for mileage reimbursement.

Fairness of a Cents-Per-Mile Reimbursement Program

The downside of reimbursing based on the static IRS mileage rate? It does not account for daily changes in fuel prices or differences in regional vehicle ownership costs. Instead, the IRS derives the rate from weighting and blending cost factors for a variety of vehicles across the country.

On the surface, employers believe the per-mile reimbursement approach for all drivers — regardless of territory type, location or number of miles driven — works best. Companies often see treating employees equally as one and the same with treating employees equitably. However, when drivers have widely varying travel or expense patterns, reimbursements treat them inequitably under a uniform mileage reimbursement structure.

How the IRS Mileage Rate Can Be Unfair

Some vehicle costs, like insurance, fuel, vehicle registration, etc., vary substantially by geographic area. These can drive wide differences in vehicle ownership and operating costs for drivers. As a result, using a flat cents-per-mile, like the IRS rate, can incorrectly reimburse employees based on regional costs.

When used for frequent travelers, the IRS standard mileage rate also tends to under-reimburse low mileage drivers and over-reimburse high mileage drivers. Consider an employee in Detroit required to drive their personal car for work. Say they only drive about 5,000 business miles a year. The employee would receive $3,350 using the current IRS rate of 67 cents. That may not even cover his or her insurance premiums (they can top $5,000 in some Detroit zip codes). On the other hand, an employee who drives 25,000 business miles a year would receive $16,750 – over one-third the price to buy a brand new car and a hefty over-reimbursement for the majority of us. As a result, a more dynamic mileage reimbursement is best if you have a true mobile workforce. Fixed and variable rate (FAVR) programs for example allow employers to more accurately reimburse their employees who drive regularly for business.

Customized, IRS-Compliant FAVR Reimbursement Programs

Like the IRS mileage rate, reimbursements calculated under a FAVR program are eligible for tax-free status. However, under a FAVR program, employees receive customized mileage reimbursements are customized for each employee based on their location and business miles. Employees in high cost areas like Detroit receive a higher fixed reimbursement than those in low cost areas. Additionally, employees’ variable reimbursements account for both current fuel prices and their business mileage. By taking these unique variables into consideration, FAVR reimbursements more accurately reflect the driving costs employees incur.

Although a FAVR program is typically more accurate and cost-effective than the federal mileage reimbursement rate, there are some limitations. There are various guidelines for reimbursements to qualify for tax-free status, among which are the following: employees must drive at least 5,000 business miles a year, and at least five employees must be reimbursed using the FAVR methodology at all times during the year. And while employers can still choose to use the FAVR methodology regardless, any reimbursements paid in excess of the IRS mileage rate would automatically be subject to tax.

Choosing the Right Mileage Reimbursement Program

This federal mileage reimbursement rate is typically the most effective solution for employees who drive sparingly for business. Especially if they don’t meet the minimum 5,000-mile threshold to qualify for tax-free reimbursements on a FAVR program. These employees tend to make one-off business trips rather than relying on their cars each day to perform their jobs. The IRS mileage rate also tends to be the best option for companies with less than five employees who regularly drive for work, since it allows mileage reimbursements to be paid 100% tax-free.

Once a company’s mobile workforce grows to five employees who regularly drive for work, a FAVR plan becomes a more cost-effective option. It provides a more accurate reimbursement by accounting for employees’ individualized costs; it eliminates over and under-reimbursements; and it allows tax-free reimbursement within IRS guidelines.

But oftentimes, it’s not a one-size-fits-all scenario. Companies tend to have a diversified workforce, with some employees practically living in their cars for work and other employees driving less frequently. Fortunately, it doesn’t have to be one mileage reimbursement program or the other. Combined cents-per-mile and FAVR programs adjust the reimbursement methodology based on employees’ driving behaviors. By combining the two and choosing a partner like Motus to manage both programs, companies can gain an optimized vehicle program that is tailored to their employee population and provides the most cost-effective and accurate reimbursements.