Indirect cost allocation for federal government contractors: building rates you can explain and support

Government contractors do not always bid work as one fixed price. On some U.S. federal contracts, the Government reimburses allowable costs incurred during performance, including an allocable share of allowable indirect costs. 

This is where indirect cost allocation comes in. You need a reasonable way to determine how much of those shared costs belong to each contract. The resulting indirect rates can affect what you propose, what you bill, and what a contract ultimately earns.

If your company already uses indirect rates, the bigger question is whether the structure behind them still reflects how your business operates. A rate that worked well several years ago can become less useful as you add employees, increase subcontracting, change locations, or take on work with a different cost profile.

This article explains some of the basic mechanics, why indirect rates move, and what those changes can mean for pricing, profitability, and cost recovery.

How are indirect cost rates calculated?

Start with the difference between direct and indirect costs. A direct cost can be identified with a particular contract. If an engineer works 40 hours specifically on Contract A, that labor may be charged directly to that contract.

Indirect costs support more than one contract or business activity. Think about accounting staff, office expenses, employee benefits, or managers who oversee several projects.

Those shared costs are grouped into a cost pool and allocated using a base.

Indirect cost pool ÷ allocation base = indirect rate

Suppose you have $900,000 of engineering overhead and $3 million of direct engineering labor in the allocation base. Your overhead rate is 30%.

That percentage gives you a method for assigning a share of the $900,000 to the contracts benefiting from those costs. So the rate itself is not the starting point. It is the result of two decisions: which costs belong in the pool and which activity should absorb them.

One important distinction is that allocable does not automatically mean allowable. Some costs may be part of your accounting records but still unallowable for reimbursement under the FAR. Examples can include entertainment costs, certain interest expenses, and some lobbying activities. Those costs must be identified and excluded from applicable Government billings, claims, and proposals. But that does not necessarily mean removing them from the allocation base. Costs that properly belong in the base generally remain there and continue to absorb their share of indirect costs. 

Why did your indirect cost rate increase?

If you start seeing higher indirect rates, that doesn’t necessarily mean you spent more. 

Assume you have a $1.2 million overhead pool and a $4 million direct labor base. Your rate is 30%. Now suppose more of your work is subcontracted and direct employee labor falls to $3 million. Your overhead remains about $1.2 million. Your rate rises to 40%.

The company did not spend more on overhead. There is simply less direct labor over which to spread those costs.

That matters because the rate may be used in pricing new work or measuring contract costs. If you assume the rate will stay at 30% when current operations point toward 40%, your pricing and margin expectations can be off. So when a rate changes, be sure to look separately at what happened to the cost pool and what happened to the allocation base.

Does your allocation base still fit your business?

An allocation method can be reasonable when you create it and become less useful as the company changes.

Maybe you now subcontract much more work. Perhaps a larger share of your employees work at customer sites. You may have opened a new location or developed a business line with a very different cost profile.

Those changes can affect which contracts benefit from your indirect costs.

Suppose your company has a large group working at customer sites and a smaller headquarters team. The field employees may use less office space and internal infrastructure than headquarters employees. If one overhead pool allocates those costs across everyone in the same way, some contracts may absorb more of the shared cost than the underlying activity supports.

That may be a reason to reconsider the structure.

Review each major pool by asking what drives the costs and which parts of the business actually benefit from them.

How do fringe, overhead, and G&A rates fit together?

Government contractors commonly use several indirect cost pools rather than one company-wide rate:

• Fringe generally captures employee-related costs such as payroll taxes, health insurance, paid leave, and retirement benefits.
• Overhead usually relates to an operating function or department. Examples might include indirect supervision, shared technical software, supplies, or certain facility costs.
• General and administrative expenses (G&A) generally cover costs associated with running the business as a whole, such as executive management, accounting, legal services, and corporate administration.

The exact structure varies by contractor. What matters is that costs grouped together have a reasonable relationship and that the allocation base reflects the activities receiving the benefit.

If the business has changed substantially since you created the structure, those assumptions deserve another look.

Can indirect cost allocation affect contract pricing and margins?

Indirect rates matter because they help determine the full cost of performing the work. But the financial impact depends in part on the type of contract.

On a fixed-price contract, you agree to perform the work for a set price. If you underestimate your indirect costs when you build the proposal, you may still receive the same contract price while absorbing more cost than expected. That can reduce your margin.

Suppose you are preparing a bid with $500,000 of direct labor. At a 30% overhead rate, that labor would absorb $150,000 of overhead. At a 40% rate, it would absorb $200,000. That’s a $50,000 difference before fringe, G&A, or other indirect costs enter the calculation. And that extra cost can come directly out of expected profit.

Cost-reimbursement contracts work differently. Subject to the contract terms and applicable rules, the Government may reimburse allowable direct costs and an allocable share of allowable indirect costs. In that case, the indirect rate helps determine how much allowable shared overhead and other indirect cost is assigned to the contract. Interim billing rates may also be adjusted later when final rates are established.

So an inaccurate rate assumption can create problems under either type of contract. On fixed-price work, the risk often shows up in margin. On cost-reimbursement work, it can affect cost allocation, billing, and later adjustments.

For significant proposals, do not automatically carry forward last year’s rate. Look at the expected pool and base for the period in which you will perform the work.

Are you estimating and accounting for costs consistently?

How you classify a cost when you prepare a proposal should generally match how you account for similar costs during performance.

Suppose your proposal treats project administration as an indirect overhead cost. After award, your team starts charging similar project administration directly to that contract. Now you’ve priced the work under one set of assumptions and accumulated the actual costs under another.

That can distort your internal margin reporting and raise questions about whether costs are being treated consistently.

Take a recent proposal and trace its major cost assumptions into your accounting records. Look at direct labor, project management, travel, shared software, and other significant costs. You should be able to explain why each category receives the treatment it does and apply that logic consistently.

Why can billing rates differ from actual indirect rates?

On applicable contracts, the Government may reimburse indirect costs during the year using temporary billing rates before final indirect cost rates are known.

Those billing rates are intended to approximate the final rates, but actual experience can change during the year. FAR 42.704 provides for billing rates to be revised when needed to help prevent substantial overpayment or underpayment.

Let’s say you’re billing overhead at 32%, but current results indicate the year may finish closer to 39%. The 32% rate may still determine interim reimbursement, but it no longer gives management the best picture of the contract’s expected economics. The reverse can happen too. If your billing rate is above the rate you now expect to finish with, later adjustments may be necessary.

Compare billing rates with current forecast rates during the year rather than assuming the two will remain aligned.

How often should you review indirect cost rates?

For many contractors, waiting until year-end is too late to discover that a rate has moved materially.

A quarterly review is often a practical starting point. Companies experiencing rapid growth, major contract turnover, or significant changes in subcontracting or headcount may want to review rates more frequently.

For each major rate, compare:

The differences tell you where to investigate.

If your pricing rate is lower than your current forecast, is that intentional? If your billing rate has drifted away from expected actual experience, should it be reviewed? And if a rate rose because the base shrank, is that a short-term change or part of a new business model?

Those questions are easier to address during the year than after the books close.

Your indirect rate structure should be easy to explain

A spreadsheet showing a 36.7% overhead rate proves the calculation. It does not prove that the method behind it still makes sense.

For each major pool, you should be able to explain what costs it contains, which base you use, and why that base reasonably spreads the costs among the contracts or activities benefiting from them.

You should also understand what caused a material rate change.

A useful starting point is to list each major indirect pool, the dollars in the pool, its allocation base, and the resulting rate. Then ask: if you were setting up the structure today, would you do it the same way?

If not, it may be time to revisit more than the percentage. For more personalized guidance, please contact one of our expert advisors.