The problem isn't that BOEs are complicated. The problem is that everything you need to build one lives somewhere different.
It starts simply enough. Your prime sends over a solicitation. You've done this before. You know what a BOE looks like. You open Excel, start a new tab, and get to work.
Four days later you're still at it.
Not because the work is beyond you. Because building a competitive BOE for a defense subcontract requires pulling information from a dozen different places — and none of them talk to each other.
Most defense small business owners underestimate how long a BOE takes because they don't account for the hunting.
Before you write a single number, you're already pulling from five or six different sources:
Your previous BOEs — buried in a folder somewhere, formatted differently each time, with labor rates that may or may not still be accurate.
Your LCAT definitions — if you have them documented at all. KSAs, clearance requirements, salary bands, fringe rates. Scattered across old proposals, HR files, or someone's memory.
GSA per diem rates — which means navigating to the GSA website, searching by destination city, hoping the rates haven't changed since you last checked, and manually entering them into your travel tab.
JTR rules — because your prime's subcontract will require JTR compliance, which means 75% M&IE on travel days, specific lodging caps, and mileage rates that change annually.
Your indirect rates — which might be in a separate spreadsheet, might be in your accounting system, might be a number your CPA gave you six months ago.
And then the solicitation itself — the PWS, the CLIN structure, the period of performance dates, the WBS breakdown your prime expects — which you're constantly flipping back to as you build.
By the time you've gathered all of it, you've spent a day and a half just finding the inputs. You haven't built anything yet.
Once you have your inputs, you start building the work breakdown structure. This is where most small firms lose another full day.
Your prime expects the WBS to reflect the tasks in the PWS. But translating a statement of work into a logical WBS structure — one that assigns the right LCATs to the right tasks, with hours that are defensible — requires judgment and iteration.
In a spreadsheet, every change cascades manually. You adjust hours on one task and you're back to checking every formula downstream. You add a new LCAT and you're reformatting columns, checking rate references, updating the cost summary tab.
The WBS isn't the hard part intellectually. It's the hard part mechanically.
Assigning the right labor categories to each WBS task is where proposals get won or lost — and it's also where small firms are most exposed.
If your LCAT library lives in a spreadsheet — or worse, if you're rebuilding it from scratch on every proposal — you're making rate decisions without a clean historical baseline. You're guessing at hours because you don't have a record of what similar tasks took on your last contract. You're assigning clearance requirements from memory.
And when your prime's contracts team pushes back on your rates or your LCAT mix — which they will — you don't have documentation to support your numbers.
Every defense subcontract BOE with travel in it has the same travel tab problem.
You need to pull GSA lodging rates by city. You need to calculate M&IE at 75% for departure and return days. You need to account for rental car rates, airfare estimates, and per diem for each travel event across the period of performance.
Doing this correctly requires cross-referencing the GSA website, the JTR, and your own calendar assumptions — every single time. For a subcontract with quarterly site visits to three different locations, that's a significant chunk of time just for the travel section.
By the time you get to the cost summary, you're exhausted. You've been bouncing between tabs, cross-referencing sources, and manually checking formulas for days.
The cost summary should be the easy part — it pulls from everything you've already built. But in a spreadsheet, "pulls from" means cell references that break when you add a row, formula errors that are invisible until your prime's reviewer catches them, and a document that looks different from the last BOE you submitted.
And then the spendplan. Your prime wants to see how the budget distributes across the period of performance. Monthly. Do you front-load it? Even distribution? Back-load toward the option periods? In a spreadsheet, you're building that distribution by hand every time.
If you're a small defense firm submitting four to six proposals a year, and each BOE takes three to five days to build — that's up to 30 days a year spent on proposal construction alone.
That's not counting the revisions when your prime comes back with questions. That's not counting the errors that make it into final submissions because you were too tired on day four to catch them. That's not counting the proposals you didn't submit because the timeline was too short for your manual process.
For a firm billing $150 to $250 an hour on contract, 30 days of proposal labor is $180,000 to $300,000 in opportunity cost annually. Spent hunting for inputs, reformatting spreadsheets, and manually checking formulas.
The problem isn't that BOEs are complicated. The problem is that the tools most small defense firms use weren't built for them.
A purpose-built BOE tool starts with your LCAT library already loaded — rates, KSAs, clearance requirements, all versioned by fiscal year. GSA per diem rates pull automatically by destination. JTR rules are applied without you having to look them up. The WBS structure matches what your prime expects.
When you assign an LCAT to a task, the rate pulls from your library. When you add a travel event, the M&IE calculates at 75% for travel days automatically. When you finish the BOE, the cost summary builds itself. When you're ready for the spendplan, the period of performance dates and total budget are already there — you choose your distribution and it generates.
The BOE that used to take four days takes a few hours. The inputs that used to require six different sources are in one place. The formulas that used to break when you added a row don't exist anymore.
That's what AVERNORTH's BOE Builder is designed to do — not as a spreadsheet replacement, but as a purpose-built tool for the way defense subcontract proposals actually work.
If your next proposal is due in five days and you're already dreading the build, it might be time to try a different approach.
AVERNORTH's BOE Builder connects your LCAT library, GSA rates, JTR rules, cost summary, and spendplan in one place — built specifically for defense subcontractors.
Start your free 14-day trial →