What it means
The category exists because chasing receipts for a $2 tip costs more in administrative time than the tip itself. Employers therefore set a small fixed rate per travelling day, and the traveller claims it without proof of the individual items.
Larger identifiable costs such as flights, hotel rooms and client meals stay outside the incidental allowance and are claimed separately. What counts as incidental varies by policy, and the boundary is worth writing down.
Tips to porters and housekeeping, baggage fees, laundry and dry cleaning on trips over a certain length, and small transport charges are common inclusions. Personal items, entertainment, in-room films and anything with a clear business receipt are usually excluded.
Tax treatment is a big part of why the flat rate approach is popular. In many jurisdictions a per diem paid at or below an officially published rate is treated as a reimbursement rather than taxable pay, so neither the employer nor the employee picks up an extra liability.
Paying above the published rate can make the excess taxable, which is why finance teams check the published figures before setting policy. For accounting purposes incidentals are an operating expense, usually posted to travel and subsistence and allocated to the department or project that generated the trip.
They are small individually and material in aggregate, which is exactly the profile that makes them easy to under-budget. A team of thirty people travelling twenty days a year at a modest daily rate is a real line in the annual plan.
The control question is consistency rather than tightness. A clear published rate, applied to everyone on the same terms and reviewed annually, prevents both the arguments about what counts and the slow drift into treating the allowance as an untaxed bonus.
Auditors will look for evidence that the rate was applied to genuine travelling days only.
In practice
Real-world examples.
Example
A sales manager on a four-day regional trip tips hotel porters, pays a checked-bag fee and has two shirts laundered. Rather than submitting three small receipts, she claims the company's $8 daily incidental allowance for a total of $32. Her expense report has one line instead of several.
Example
An engineering firm sending technicians offshore for two-week rotations raises its incidental rate for those trips, because laundry and personal supplies are genuinely higher when someone is away that long. The rate is published in the travel policy so no one has to negotiate it individually.
Example
A charity discovers that incidental claims have crept up because staff have been including client coffees and taxi fares that should be claimed as separate business expenses. The finance officer rewrites the policy with an explicit list of what the allowance covers and reduces double-claiming almost immediately.
Formula
Calculation
Incidental expense reimbursement = Daily incidental rate x Number of qualifying travel days x Number of travellers.
A consulting firm sets its incidental allowance at $6 per travelling day, in line with the published rate it uses for tax purposes. It sends 8 consultants to a client site for a 5-day engagement.
Each consultant claims $6 x 5 = $30 for the week. Across the team the total is $30 x 8 = $240. If the firm runs 40 such engagements in a year, the annual incidental cost is $240 x 40 = $9,600, which is budgeted within travel and subsistence.Case study
Seen in the real world.
Calderwell Advisory is a fictional professional services firm used purely to illustrate the point. Its travel policy required receipts for every expense, including tips and baggage charges, and its finance team spent an estimated 60 hours a month processing claims under $10.
The firm switched to a flat $7 daily incidental allowance for travelling days, keeping receipt requirements for flights, hotels and client entertainment. Processing time on small items fell to almost nothing, and the total amount reimbursed changed by less than 3%, because the allowance closely matched what people had actually been claiming.
The illustrative point is that the saving came from administration rather than from the expense itself. Calderwell reviews the rate each year against the published tax-free figure so the allowance stays outside taxable pay.
Watch out
Common mistakes.
- Treating every small business cost as an incidental. Client meals, taxis to meetings and conference fees are separate expense categories with their own receipt rules.
- Paying an incidental allowance for non-travelling days. The allowance applies only to days genuinely spent away on business, and paying it more widely can make it taxable pay.
- Setting a generous rate to keep staff happy without checking the published tax-free limit. Anything above the limit creates a payroll tax liability for both sides.
Questions
People also ask.
Do employees need receipts for incidental expenses?
Usually no, which is the main reason for using a flat daily rate, though the travel dates themselves must be evidenced.
Are incidental expenses tax deductible for the business?
Yes, they are an ordinary business expense provided they relate to genuine business travel and are properly recorded.
How should the rate be set?
Start from the officially published per diem incidental figure for your jurisdiction and review it annually rather than leaving it unchanged for years.
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